Plants of the World: An Illustrated Encyclopedia of Vascular Plants 9780226536705

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Plants of the World: An Illustrated Encyclopedia of Vascular Plants
 9780226536705

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PLANTS OF THE

WORLD

To our parents Benno Christenhusz and Gerdi Leussink Hugh and Doreen Fay Wayne and Helen Chase and Amy Morris

who all nurtured our interest in nature and encouraged our studies in botany

PLANTS OF THE

WORLD

AN ILLUSTRATED ENCYCLOPEDIA OF VASCULAR PLANTS Maarten J. M. Christenhusz

Michael F. Fay

Kew Publishing Royal Botanic Gardens, Kew

The University of Chicago Press www.press.uchicago.edu

Mark W. Chase

© The Board of Trustees of the Royal Botanic Gardens, Kew 2017 Text © the authors Photographs © M. Christenhusz unless stated otherwise on page 672 The authors have asserted their rights to be identified as the authors of this work in accordance with the Copyright, Designs and Patents Act 1988. All rights reserved. No part of this publication may be reproduced, stored in a retrieval system, or transmitted, in any form, or by any means, electronic, mechanical, photocopying, recording or otherwise, without written permission of the publisher unless in accordance with the provisions of the Copyright Designs and Patents Act 1988. Published in 2017 by Royal Botanic Gardens, Kew, Richmond, Surrey, TW9 3AB, UK www.kew.org and The University of Chicago Press, Chicago 60637, USA 26 25 24 23 22 21 20 19 18 17    1 2 3 4 5 Kew Publishing ISBN 978 1 84246 634 6 e-ISBN 978 1 84246 636 0 The University of Chicago Press ISBN-13: 978-0-226-52292-0 (cloth) ISBN-13: 978-0-226-53670-5 (e-book) DOI: 10.7208/chicago/9780226536705.001.0001 Great care has been taken to maintain the accuracy of the information contained in this work. However, neither the publisher nor the authors can be held responsible for any consequences arising from use of the information contained herein. The views expressed in this work are those of the authors and do not necessarily reflect those of the publisher or of the Board of Trustees of the Royal Botanic Gardens, Kew. British Library Cataloguing in Publication Data A catalogue record for this book is available from the British Library. Library of Congress Cataloging-in-Publication Data Names: Christenhusz, Maarten J. M., 1976 – author. | Fay, Michael F., 1960 – author. | Chase, Mark W., 1951– author. Title: Plants of the world : an illustrated encyclopedia of vascular plants / Maarten J. M. Christenhusz, Michael F. Fay, and Mark W. Chase. Description: Chicago : The University of Chicago Press, 2017. Identifiers: LCCN 2017013690 | ISBN 9780226522920 (cloth : alk. paper) | ISBN 9780226536705 (e-book) Subjects: LCSH: Plants—Encyclopedias. | Plants—Pictorial works. Classification: LCC QK7 .C47 2017 | DDC 580.3—dc23 LC record available at https://lccn.loc.gov/2017013690 ∞ This paper meets the requirements of ANSI/NISO Z39.48-1992 (Permanence of Paper). Copy editors: Ruth Linklater, Sharon Whitehead Design, typesetting and page layout: Nicola Thompson, Culver Design Production Management : Andrew Illes Cover image: Freycinetia impavida (Pandanaceae), in fruit, Tahiti, French Polynesia (© M. Christenhusz). Back cover images (from top to bottom): lycopod: Selaginella willdenowii (Selaginellaceae), Malaysia; fern: Angiopteris evecta (Marattiaceae), Moorea, French Polynesia; gymnosperm: Picea likiangensis (Pinaceae),Yunnan, China; magnoliid: Magnolia hypoleuca (Magnoliaceae), North Carolina, USA; monocot: Dracula verticulosa (Orchidaceae), Ecuador; eudicot: Cochlospermum fraseri (Bixaceae), Northern Territory, Australia Printed and bound in China by C&C Offset Printing Co., Ltd

For information or to purchase all Kew titles please visit shop.kew.org/kewbooksonline or email [email protected] Kew’s mission is to be the global resource in plant and fungal knowledge, and the world’s leading botanic garden. Kew receives about half of its running costs from Government through the Department for Environment, Food and Rural Affairs (Defra). All other funding needed to support Kew’s vital work comes from members, foundations, donors and commercial activities including book sales.

CONTENTS

vi 1 3 4 6 8

How to use this book Introduction Evolution of land plants Plants and human culture Naming plants Classification and the Angiosperm Phylogeny Group

13 Fossil plants 14 Families 14 Etymology and common names 15 Genera 15 Phytogeography 16 Economic botany 18 Lycopods 22 Ferns

71 Gymnosperms 88 The ANA grade families 95 Magnoliids 115 Monocots 213 Eudicots 638 Glossary 671 Acknowledgements 672 Photography credits 673 Further reading 753 General references 756 Index

HOW TO USE THIS BOOK For an explanation of how plants are scientifically named and how their relationships are studied, see pages 6–8, and for the types of plant groups, their relationships and how they are visualised, see pages 8–12.

MAGNOLIALES

Order description with thumbnail illustration of phylogenetic tree and magnifying glass icon showing its position on the tree. See full-size tree on page 11 for more detail.

MAGNOLIALES Families 49 to 54 form the order Magnoliales. These woody plants can be recognised by their often two-ranked or spirally arranged leaves. Their petals are whorled (or spirally arranged) and their medium-sized seeds have an irregular ruminate endosperm (like nutmeg).

49. MYRISTICACEAE Nutmeg family

Family number and scientific name followed by common name. See page 14 for information on plant families and common names. These aromatic, often dioecious trees, sometimes shrubs, have red sap and red, long terminal buds. Leaves are simple, alternate, often oriented in a plane, short-petiolate and without stipules. Leaf margins are entire, and hairs on the leaf surfaces and stems are usually branched or stellate. Inflorescences are panicles or fascicled racemes. Flowers are small, actinomorphic and funnel-, bell- or urn-shaped. Tepals are usually three, basally fused and often fleshy. Male flowers have two to 40 stamens with fused filaments. Female flowers have a single carpel, superior ovary and bilobed stigma. The fruit is a fleshy to woody capsule, usually splitting in half, Myristica fragrans, Singapore (MC) [49]

Description of key characteristics of the family.

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exposing woody seeds that are usually covered in a lacy or entire, leathery or fleshy aril. Distribution: This is a pantropical family that are often canopy trees in rainforests.

Map showing approximate native range for the family (marked in orange). The accompanying text includes climatic and habitat information. See page 15 for further information.

Number of genera and number of species followed by a list of genera, with species numbers for each genus given in brackets. See pages 6–7 for more information on the naming of plants and page 15 for more information on genera.

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Phylogeny and evolution: Myristicaceae clearly belong to core Magnoliales, which probably evolved >100 million years ago. They are well supported as sister to Degeneriaceae. Fossils from upper Cretaceous deposits in the Sahara are known, and Eocene fossil seeds are known from Europe, e.g. from the London clay. Diversification of modern lineages happened fairly recently, c. 15–20 million years ago. Genera and species: Myristicaceae include 21 genera with c. 520 species: Bicuiba (1), Brochoneura (3), Cephalosphaera (1), Coelocaryon (4), Compsoneura (c. 19), Doyleanthus (1), Endocomia (4), Gymnacranthera (7), Haematodendron (1), Horsfieldia (c. 100), Iryanthera (20), Knema (c. 90), Mauloutchia (10), Myristica (c. 170), Osteophloeum (1), Otoba (8), Paramyristica (1), Pycnanthus (4), Scyphocephalium (4), Staudtia (1) and Virola (c. 65). Virola surinamensis, fruit, French Guiana [49]

Uses: Myristica fragrans is a tree with apricotlike fruits in which nutmeg (the seed) and mace (the aril) are formed. This native of the Banda Islands in the Maluku Archipelago (Moluccas) in Indonesia was important in the 17th century spice trade, giving the name “Spice Islands” to this region. Ground nutmeg is used as a culinary spice but with excessive use is addictive, toxic and potentially hallucinogenic. Nutmeg oil is used medicinally and for flavouring tobacco and toothpaste. Bark of Iryanthera, Virola elongata and Osteophloeum platyspermum is used locally as a hallocinogen. Gymnacranthera, Horsfieldia and Knema seeds have oils that are used to make candles. Fat from Otoba seeds is used to make soap, and Virola sebifera contains oils that are suitable for candle and soap making. Caihuba, Virola surinamensis, produces an edible oil that is similar to cocoa butter. Horsfieldia iryaghedhi, Pycnanthus angolensis, Staudtia stipitata and Virola koschnyi produce fine timbers. Etymology: Myristica is derived from the Greek μύρων (myron), a balm or ointment, probably derived from a Semitic root m’rr, meaning bitter, a cognate with myrrh. Compsoneura excelsa in fruit, Los Mogos, Osa, Puntarenas, Costa Rica (CD) [49]

HOW TO USE THIS BOOK

Informal higher category and order. See page 8 for information on taxonomic ranking.

MAGNOLIALES

MAGNOLIIDS

Tuliptree, Liriodendron tulipifera, Royal Botanic Gardens, Kew, UK [50]

Magnolia macrophylla, fruit, Nichols Arboretum, Ann Arbor, Michigan, USA [50]

Magnolia ×soulangeana (a hybrid of M. denudata and M. liliiflora), Royal Botanic Gardens, Kew, UK [50]

Magnolia stellata, private garden, Kingston upon Thames, Surrey, UK [50]

Magnolia doltsopa, Royal Botanic Gardens, Melbourne, Australia [50]

Magnolia campbellii, Royal Botanic Gardens, Kew, UK [50]

50. MAGNOLIACEAE

scent and attracting pollinators. The fruit is cone-like with free or fused follicles. In many species the carpels dehisce, and the pendent seeds exhibit a red aril.

flowers, Pachylarnax with few carpels but many ovules per carpel, and Talauma with fused carpels. These genera have, however, been found to be embedded in Magnolia sensu lato, expanding that genus to > 250 species, a number that is still growing. The two species of Liriodendron are well-supported as sister to Magnolia. Magnoliaceae are probably sister to the rest of Magnoliales.

Tuliptree family

Distribution: The family has a disjunct distribution in eastern North America, tropical America (Mexico to Brazil and Peru), southern India, Sri Lanka, the Himalayas and throughout temperate and tropical East Asia (Japan and Korea to New Guinea). These trees and shrubs have simple, entire and lobed, spirally arranged and petiolate leaves and stipules that enclose the bud and sheath the stem; these soon fall off leaving a scar. Stalked flowers are formed singly on the end of branches or short axillary shoots. Petals are free, six or more, spirally or whorled, sometimes differentiated into sepal-like outer petals and petal-like inner ones. Numerous stamens are free and spirally arranged, the filaments short or elongate, often flattened, and the anthers are elongate with the connective produced into a tip. Ovaries are superior, often stalked. Carpels are usually numerous, sometimes few, spirally arranged and free. Beetles are the most frequent pollinators, and some species create heat in their flowers, increasing the dissemination of

Phylogeny and evolution: The 98 million year old fossil flower Archaeanthus and fossil fruits of Lesqueria have been assigned to Magnoliaceae. Liriodendron in particular was widespread across the Northern Hemisphere during the late Cretaceous and Tertiary. Numerous now extinct lineages have been recorded from fossils. More modern representatives appeared in the late Miocene in Eurasia, especially when compared to North American extant taxa, which are considerably older. Several modern genera were described on the basis of deviating morphological characters not found in Magnolia sensu stricto; these include Elmerillia with sessile ovaries, Kmeria with unisexual flowers, Manglieta with four or more ovules per carpel, Michelia with axillary

All families are represented by one or more images, showing key characteristics as well as the diversity of the group. Captions include plant name and place where photographed (if known). Numbers in blue indicate the family number.

List of major economic uses including traditional and modern uses for food and construction, and religious, cultural and recreational practices, with notes on cultivation of ornamental species. See pages 4–5 and 16 for more information.

Origin and meaning of the scientific name on which the family name is based. For more information see page 7.

Genera and species: This is now a family consisting of just two genera with c. 267 species: Liriodendron (2) and Magnolia (c. 265). Uses: Essential oils from Magnolia champaca are used for perfumery; its leaves are used to feed silk worms. Timber of Magnolia is used for boxes, matches, engraving, flooring, broom handles, traditional Japanese shoes etc. Wood of Liriodendron (whitewood) is used for furniture, shingles, latches and formerly canoes. Many species are highly valued ornamentals. Etymology: Magnolia was named in honour of French botanist Pierre Magnol (1638–1715), who was the first to publish plant families in an intrinsic ‘natural’ classification. Plants of the World

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Discussion of the evolutionary history including important fossils, former and current ideas about relationships and groupings within the family (e.g. subfamilies, clades). See pages 3 and 13 for further information.

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INTRODUCTION When thinking of biodiversity, animals first come to mind for most people. Also, when people think of a tropical rainforest, they imagine walls of green vegetation with lots of animal life: monkeys, tapirs, panthers, snakes, colourful birds and butterflies. Perhaps there are some flowers in the rainforest too, but these are just bright blobs of colour without specific parts, and all too often people seem to forget the enormous diversity of plants that provide home, food and support for these emblematic animals. Without healthy and diverse forests of bamboo, there will be no pandas. Because of this ‘green blindness’, conservation efforts and the funding associated with these are often directed towards the protection and study of large mammals, birds and reptiles (roughly the same animals that dominate nature television documentaries), but conserving these animals is directly related to conserving their habitats and preserving the botanical diversity of which they are composed. No large mammals, including humans, can exist without the input from primary producers, the plants. Plants not only provide oxygen, food and shelter, but they also capture and purify water and provide numerous medicinal compounds needed to fight or ease diseases of animals including humans. Plant diversity parallels or exceeds most animal diversity, so there is no excuse for green blindness. With an estimated 321,000 species, plant diversity is much greater than the number of vertebrates (62,300), of which only 5,490 are mammals and some 10,000 are birds, small groups that receive lots of scientific attention in comparison. Only arthropods, including insects, spiders, scorpions, lobsters and crabs, have greater

diversity (c. 1,234,000 species), but these are also dependent on plants. The diversity and evolution of insects and land plants have proceeded hand-in-hand. Of course, there are organisms that happily thrive without plants; some detritivores, such as many fungi and bacteria, and some arthropods that have specialised on feeding on detritivores can exist without the input of land plants. These existed before plants evolved, but the organismic diversity of the world would be much diminished and different if plants did not exist, and of course human civilisation totally depends on our green friends. Plants absorb sunlight via chlorophyll in their leaves. Through photosynthesis, plants convert light energy into chemical energy in the form of carbohydrates, such as sugar and starch, that can later be released to fuel activities of the plants. This process is the most efficient energy conversion known in the living world, and this efficiency makes plants the powerhouses of our planet. Because sunlight is essentially limitless and photosynthesis so efficient, plants can produce more carbohydrates than they need for their own growth, and these can be employed to produce nectar to attract pollinators or to pack their fruits and seeds with extra nutrients to attract animals to disperse their seeds. Plants use animals to their benefit, and animals in turn, often unknowingly, help plants to achieve their reproductive goals: fertilisation of egg cells and dispersal of seeds. The flowering plants in particular are so efficient at reproducing themselves (sexually and asexually) that they are good sources of food for animals, but plants have in response developed a large diversity of chemical

compounds to combat being eaten. Therefore, many plants make poisons, but many of these, given at precise dosages, can also be employed as medicines or pesticides. Humans have thus benefited from plant defence mechanisms. In addition, humans avoided poisoning by domesticating plants to produce toxin-free resources to feed ever-burgeoning human populations, but these domesticated plants have in turn also benefited from this symbiosis and are now distributed in huge numbers worldwide under the protection of their human benefactors. We now know that the flowering plants are unique in that they have had multiple rounds of polyploidy, after which most of the extra copies of genes were stripped from their genomes, so that they retain only large numbers of controlling genes (transcription factors and gene regulators), which are used to provide more sophisticated patterns of gene expression, giving them advantages over other kinds of plants and allowing them to better utilise available resources. Higher chromosome numbers are the initial result of these polyploid events, but these episodes are followed in many plants by chromosome condensation/reorganisation, resulting in herbaceous species with low chromosome numbers, self-pollination and annual life histories, which are highly suited to domestication and production of large amounts of carbohydrates. Without the resources provided by annual herbaceous flowering plants (e.g. rice, maize, wheat, beans, tomato, lettuce, gourds etc.), it is difficult to imagine how human civilisations could ever have developed. Imagine trying to feed large cities on the resources provided

Orchis Bank, near Downe (Kent, UK) was one of Charles Darwin’s favourite spots. The diversity of plants and animals on this herb-rich hillside on chalk provided Darwin with an ideal place to observe orchids (e.g. Anacamptis pyramidalis, Orchidaceae, foreground) being pollinated by insects, climbing plants including Bryonia dioica (Cucurbitaceae) and Dioscorea communis (Dioscoreaceae), plant movement (Oxalis acetosa; Oxalidaceae) and heterostylous species of Primula (Primulaceae). The fundamental studies he carried out there featured prominently in his books and seminal works on orchid pollination, climbing plants, the power of movement in plants and heterostyly.

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INTRODUCTION

Figure 1a. Plants on masonry, Gymnocarpium dryopteris (Aspleniaceae) on a wall in Uppsala, Sweden

by clubmosses, ferns and gymnosperms – it would have been impossible. Imagine an office without ink, coffee, tea, sugar or milk, let alone chocolate digestive biscuits, without which this book would not have been written. The diversity of habits, leaves, flowers and fruits of land plants is incredible. Plants grow in almost every habitat on the planet. They can be found in salt and fresh water, under icy glaciers and in hot deserts, completely underground or hanging in the air on exposed branches in the forest canopy. They even invade man-made structures, like masonry, concrete, asphalt, fences and electrical wires (Figure 1). Desirable or not, plants are practically everywhere. They drive our climate, provide drinking water, produce much of our food, medicine and construction

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Figure 1b. Plants on wires, Tillandsia recurvata (Bromeliaceae) in Tamaulipas, Mexico © Panoramio, wikimedia commons

material, beautify our world and make our planet a pleasant place in which to live. Of course several books have addressed the diversity of plants in the past, but DNA studies from the mid-1990s onward have revolutionised our ideas about classification and the evolution of the land flora. The diversity of plants is therefore here organised in an evolutionary sequence, placing closely related families near each other. Because a book is two-dimensional, we have to present the plant families in a linear sequence, which is to a degree artificial; in many cases the family placed next to another is equally closely related to the next two or more families that follow it, but there is a convention followed by most authors who use this sort of system, and we follow here the linear system as proposed

in the current version of the Angiosperm Phylogeny Group classification (APG IV 2016) and similar recent classifications for ferns and gymnosperms (Christenhusz & Chase 2014, Christenhusz et al. 2011). All families are represented here by one or more images, illustrating the diversity of the group and allowing comparisons. We aim to provide a useful overview of the botanical diversity of our green planet and hope the result is enjoyable. Our intention is that this book will provide an introduction to the wall of green that surrounds us, maybe even be a cure for ‘green blindness’, and we would be most unhappy if our readers do not go out and see for themselves what wonders the plant world has on display!

EVOLUTION OF LAND PLANTS As little as 30 years ago, the evolution of plants was portrayed as a linear, fairly straightforward increase in complexity. For example, Psilotum and Equisetum were considered perhaps to be related to the earliest vascular plants because they were at least superficially similar in appearance to fossils from the Devonian and Silurian. The complex algal charophytes were considered the closest relatives of land plants simply because they looked superficially like aquatic vascular plants. However, this comfortable sequence of plant evolution has in the past 20 years been challenged and shown to have been much more complex than previously assumed. Land plants (often called ‘Embryopsida’, but here Equisetopsida) form a lineage that is most closely related to just one genus of the green algae, Coleochaete. The early vascular plants are lycopods, whereas Psilotum and Equisetum are now known to be closely related to ferns, in which we now classify them. When plants emerged on land is not precisely known, but the estimated dates vary from 439 to 912 million years ago, although most estimates fall around 480–500 million years. Land plants can be distinguished by having sporopollenin in the spore wall, which probably facilitated their spread on land because it protects their spores from dehydration. The earliest land plants did not have roots, like their green algal

ancestors; in aquatic environments, roots are generally not required or are only used to secure a plant in position on the substrate. In the earliest stages of the invasion of land by plants, the functions of roots were performed by fungi in exchange for carbohydrates, and roots perhaps first evolved to make this process more efficient and less subject to the drier conditions that exist at the soil surface. Many plants today still maintain a relationship with fungi, called a mycorrhizal association, but some like the mustard family, Brassicaceae, appear to have foregone it. Among the earliest plants to colonise the land were relatives of liverworts, mosses and hornworts (Figure 2); also present were other groups of plants about which we know relatively little, other than their structure that is obvious from the study of their fossils; their life-history strategies are mostly in the realm of speculation. Mosses, hornworts and liverworts, collectively often termed bryophytes, exhibit the alternation of generations observed in the green algae, but they have a dominant gametophyte (the haploid generation, with one set of chromosomes). The sporophyte generation (diploid, with two sets of chromosomes) is dependent on the gametophyte. Most phylogenetic studies indicate that the hornworts alone are closer (sister) to the rest of the land plants, those with

a vascular system also called the “vascular plants”, which are the focus of this book. This term is a simplification and resulted in the bryophytes being termed “lower plants”; they do have water-conducting tissues, but these differ from those found in the remainder of the land plants, the large clade composed of the lycopods, ferns, gymnosperms and flowering plants. In all other groups of land plants, it is the sporophyte generation that is dominant; in ferns, the gametophytes are free-living and generally small, whereas in the seed plants, the gametophytes are entirely dependent on the sporophyte and not easily observed, unless one knows where to look in the developing pollen and ovary. In seed plants, pollen is released from the parent sporophyte. Pollen contains the male gametophytes, which release sperm; pollen is often considered the “male” part of a plant and described as the plant counterpart to animal sperm, but this is not strictly true. Pollen carries the sperm, and this grows out of the pollen when it lands on a stigma and makes its way via the pollen tube to the ovary where fertilisation happens. Only then is a seed formed, and seeds are inside a fruit, a structure that usually helps with the dispersal of the seed, either mechanically (explosion, wind, gravity, water) or by animals, in their fur or on their feet or inside their guts and deposited with their faeces.

Figure 2a. Liverwort: Asterella drummondii (Asterellaceae), Western Australia

Figure 2b. Moss: Polytrichum commune (Polytrichaceae), Lake District, UK

Figure 2c. Hornwort: Anthoceros agrestis (Anthocerotaceae), Germany © BerndH, wikimedia commons

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PLANTS AND HUMAN CULTURE

Figure 3a. Stone carving of Adam and Eve with the Apple of Paradise. Facade of Notre Dame, Paris, France

Nearly all animals are totally dependent on plants. Plants fix carbon into energy-rich compounds with the help of sunlight, and as a waste product they produce oxygen, which animals use to metabolise this carbon-rich fuel. However, apart from providing nutrients, food and medicine, plants are important for the development of human culture, a particular trait that sets Homo sapiens apart from other animals. There was said to be a rotten Apple in Paradise (Figure 3), and, even though the apple did give humans ‘wisdom’ and a narrative, humans had to learn how to fend for themselves in the wide world. Luckily there were plants outside the Garden of Eden as well. As soon as humans learned how to make tools, plants became directly associated with hominid culture, perhaps a stick to poke a hole to retrieve honey from a bee hive was one of the first, followed by spears and arrows to hunt and wood to build a shelter, leaves to make a roof and fibres to bind it all together. Using plant material as fuel for fire is critical in survival strategies of the past and present. Even though leather, fur and bones were frequently used by early humans for clothing and tools, fibre from cotton and

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Figure 3b. Adam naming the plants and animals. Fresco in Gran Meteora monastery, Greece.

linen were much more abundant, renewable and much easier to obtain, and this certainly helped humans to expand into much hotter and colder areas than their original climatic range encompassed. From hunter-gatherer societies that were frequently on the move, humans started to settle and form villages. This was only possible because plants (and animals) could be domesticated, and cultivation at larger scales became possible, producing more than a single farmer’s family could eat. All major seed crops are annuals (or have been selected for an annual life history if they were perennial). In addition, plants with a clear dormant period were domesticated for crops like potatoes and onions. These crop plants differ from all longer-lived species in their inherent capacity to put all their resources into the production of seeds or perennating structures (such as the

stem tubers of potato and other root crops). Little or nothing is held back by the parent plant for the following season apart from seeds and tubers, which humans can use as food and to grow the crop the following year. This massive and easily harvested product allowed farmers to sell part of their harvest in exchange for other goods and in due course, after many independent and repeated attempts, this allowed humans to diversify, specialise and develop a variety of trades and industries. The basis of communities, towns and cities was set by the domestication of plants. For the success of agriculture, whether to produce animals or plants as the final product, plants are of enormous importance. They produce fodder, make and improve soil and recycle and purify water. Despite all our accomplishments, we owe our existence to a six-inch layer of topsoil, sunshine and rain.

PLANTS AND HUMAN CULTURE Most other industries are also dependent on plants, varying from the publishing and financial sectors (paper is made of plant fibres) to all manufacturing that uses coalgenerated electricity or carbon-based fuels in their production (coal and oil are fossil plant material). Human civilisation has exceeded the mitigating ability of plants to compensate for our activities, and our stripping of vegetation from large parts of the planet has now become the biggest threat to our existence. In addition, the climate is changing due to the burning of fossil fuels and the impact humans have on life through degradation of habitats, exploitation and depletion of natural resources. Carbon that was fixed by plants hundreds of millions of years ago and held in reserve below the Earth’s surface is burned and released into the atmosphere. To a certain extent, plants have benefited from the increased levels of CO2

and are growing more quickly and larger as a result of the increase in atmospheric carbon, but the amount being released increases so rapidly that plants cannot keep up. More carbon in the air results in a changing climate, rising sea levels, more and stronger storms, freak weather events, unusual cold periods, drought, heat waves and floods. Unfortunately it is easier to secure funding for the protection of cuddly animals like lemurs or impressive large cats (and even then the money available is relatively limited) than it is to obtain funds to secure the existence of a rare species of tree, even though a local economy may be based on the fruits of these trees. Financial aid to fund a goat for a small village in the Sahel is the worst development aid imaginable. Goats increase desertification by eating all vegetation and reduce the possibility for

people to grow food locally (Figure 4). In fact eradication of goats, especially feral ones, has in many arid regions improved the water balance and allowed more sustainable food production. Exclusion of people also allows ecosystems to reset, as seen in the area around Chernobyl in Ukraine, where wildlife is now rampant. With a growing human population, climate change and political instability in many parts of the world, the need for selfsustainable, renewable, environmentally friendly livelihoods increases, and plants will play a key role in helping to achieve this. This encyclopedia lists the usefulness of many plants, some well-known crops but also other useful plants that are poorly known. We hope that this will bring the economic importance of botany to the attention of people and perhaps spark the economic use of some ‘forgotten’ species.

Figure 4. Goats climbing an argan tree (Argania spinosa, Sapotaceae) in Morocco (HR)

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NAMING PLANTS Nomenclature deals with the internationally agreed rules for naming of plants, whereas taxonomy is how and to which organisms these names should be applied. Systematics studies how these organisms are related to each other and the characters by which they can be recognised or diagnosed. These three disciplines are inter-related and should not to be confused. Taxonomy always aims for the most stable solution when new classifications and name changes are proposed, and nomenclature should help with that through the principle of priority (the first published name is generally the one that should be used). There is an elaborate system of rules to decide on the correct name that should be chosen. Unfortunately, names will have to change when it is found that species were wrongly placed, when for instance some are found to belong to a different clade (a group of uniquely related organisms) than originally assumed. Earlier these changes were made on the basis of morphological characteristics alone, which sometimes resulted in the grouping of unrelated species based on similar characters that evolved independently (convergent evolution). With the help of DNA data, comparisons of which allow us to build phylogenetic trees or assess species limits, the taxonomist has gained a valuable, less subjective tool to help assess relationships and build classifications, while at the same time taking into account morphological, anatomical and chemical similarities; all are tools in the taxonomist’s toolbox. Systematics is increasingly using various techniques from genetics to understand relationships between plants and to revise classifications. Even though some major changes of classification occurred due to the use of DNA in classification, it should be noted that many plant families have retained their traditional circumscription. Why is it important that the correct scientific names of plants are used? The main function of names is communication. When you have an internationally accepted name of an organism, information about these organisms or group of organisms (such as genera, families or orders) can be communicated without confusion. Why not use the common names of species? Common names vary from region to region and country to country. For instance, a bluebell would in England be Hyacinthoides non-scripta (Asparagaceae), in Scotland Campanula rotundifolia (Campanulaceae), in Australia Billardiera heterophylla (Pittosporaceae), in New Zealand Wahlenbergia gracilis (Campanulaceae), in Texas Eustoma grandiflora (Gentianaceae), in eastern North America Mertensia virginica (Boraginaceae) and in California Phacelia campanularia (Boraginaceae) (Figure 5). On the other hand,

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Figure 5a. Bluebell Hyacinthoides non-scripta (Asparagaceae)

Figure 5b Bluebell Campanula rotundifolia (Campanulaceae)

Figure 5c. Bluebell Billardiera heterophylla (Pittosporaceae)

Figure 5d. Bluebell Phacelia campanularia (Boraginaceae)

NAMING PLANTS the same species can have many different names in different languages. Hyacinthoides non-scripta is restricted to Atlantic Europe, from northern Spain to England, but is known variously as almindelig klokkeskilla, bell bottle, bluebell, bokidi koukou, clychau’r gog, coinnle corra, fairy flower, Hasenglöckchen, jacinthe sauvage, jacinto de los bosques, muguet bleu, wild hyacinth, wilde hyacint and wood bell, among other names. This diversity of common names for the same plant makes it difficult to find and synthesise all information published about a species. However, a stable scientific name can be used by people across all languages, geographical borders and scientific disciplines. This makes it clear which of the bluebells is being discussed, although scientific names are often omitted from the popular press because they are deemed too complicated for the general public to comprehend, whereas in fact they make life easier when you want to look things up and cause less confusion when doing so. When carrying out any type of research on plants, it is always advisable to make a dried herbarium voucher accompanied by a label stating all information you have about the specimen: name, size, stature, colour, date of collection, precise locality of collection, geographical coordinates, elevation, what study the specimen was used in and the collector’s name with a unique collection number. This specimen should then be deposited in a public herbarium, where other researchers can use it to be certain about the plant species that was studied, in case they want to repeat this study in the future. For repeatability of scientific studies, this is of incredible importance. The value of herbaria and other natural history collections is sometimes downplayed as ‘stamp collecting’, but it is much more than that. New species are still regularly found among specimens in natural history collections, and if we want to know all about the organisms with which we share our planet, understanding their distributions, habitats and changes to these, we will have to start with the material already in our collections. Natural history collections house vast amounts of information about diversity, geography, phenology etc. that we are only now starting

to use on a broader scale, especially as a result of the mass digitisation of these collections, which makes these data available on the internet. These collections also document our cultural history, because so much of human history was founded on our uses of plants. By eliminating these collections, we will lose valuable evidence about our past and potential revivable uses of plants from our history. Using these georeferenced databased collections, we can now map where target or indicator species occurred in the past versus the present and use these data to predict future distributions and extinctions under a changing climate. We can study morphological and genetic diversity of species because we are able to extract DNA from type (the specimen upon which a name is based) and other historical specimens to place taxa correctly and with certainty in a phylogenetic analysis. Also we can always go back to the original material used in previous studies, making these repeatable and thus scientific. Why do scientific names have to change? The simple answer to this common question is that names should reflect evolutionary relationships and therefore a name may have to change when our understanding of relationships has changed, usually because more data are available. Admittedly, the English bluebell referred to above was formerly known as Scilla non-scripta, Hyacinthus non-scriptus and Endymion non-scriptus, but these changes have more to do with the historical delimitation of the genera Hyacinthus and Scilla than with actual nomenclatural change, as you can see the species epithet remains the same. There are also changes as a result of the nomenclatural rules, although one of the principles is to keep names as stable as possible. The rules of priority may result in the uptake of an older, forgotten name for a species, which takes precedence over a more recent one that has commonly been in use. It is also possible that a type specimen has been erroneously interpreted and that (part of) the species needs a different name. Then there are correctable errors, listed in the nomenclatural code, where endings and conjugations may need changing. In the 1750s, Carolus Linnaeus developed

the binomial system that we use today. This simplified naming, in which all species names are composed of two names (genus and species), replaced the short descriptive phrases common in earlier times. The longer phrase names were workable as long as the number of taxa was limited, but as more of the world was explored, this system became increasingly unworkable. Shortening the phrase to two words made it much easier to remember names and grouped similar species in genera. During the late 18th and the 19th century, there were many species discovered that could not be easily placed in one of the existing genera, and so these often were placed in genera of their own. These were also often tentatively placed in a family, although evidence for some of these placements was scant. Now that we have better understanding of relationships, many species have been reorganised into genera that make more sense on the basis of molecular and morphological data. To prevent such future nomenclatural change, it has been proposed that we use the phylogenetic tree as the sole evidence of their relationships. If, for example, an unknown animal was originally described as a ‘desert goat’ because it vaguely resembled a domestic goat, but later the animal was shown to be a kind of horse instead, it would continue to be called a goat, meaning that its name then tells us nothing about its relatedness. Similarly, scientific names of species would be stable and forever remain the same. Of course, stability of names should always be taken into account when changes of names are considered, and when there are several options, the choice resulting in the fewest name changes should be preferred, especially when economically important species are involved. If this is nomenclaturally impossible, because priority is involved, a case can be made for conservation or rejection of a name, which is then voted on by the Nomenclatural Committee. For this reason, we now use the name Amaryllidaceae instead of the older name Alliaceae. However, in principle, the rule of priority should be strictly followed. We prefer to retain the current system, in which a species name contains some information about what its general relationships are.

Plants of the World

7

NAMING PLANTS Taxonomic ranks in plants have standard endings so they can be easily recognised, as for instance an order or family. These endings are as follows: Division: -ophyta, e.g. Equisetophyta (this rank is rarely used) Subdivision: -ophytina, e.g. Equisetophytina (this rank is rarely used) Class: -opsida, e.g. Equisetopsida Subclass: -idae, e.g. Equisetidae Superorder: -anae, e.g. Equisetanae Order: -ales, e.g. Equisetales Suborder: -ineae, e.g. Equisetineae (this rank is rarely used) Family: -aceae, e.g. Equisetaceae Subfamily: -oideae, e.g. Equisetoideae Tribe: -ideae, e.g. Equisetideae Subtribe: -inae, e.g. Equisetinae

All these names are based on the stem of the genus that typifies these ranks. In this case the type genus is Equisetum (stem: Equiset-), which means ‘horse bristle’, the horsetail in English. Genus names and species epithets are always written in italics with the genus name capitalised. The species epithet (the second of the two words that make up the species name) is not capitalised. Below the rank of species there are several additional ranks, mainly subspecies (subsp.), variety (var.) and forma (fo.). It has to be noted that the rule of priority applies only within a rank, not across ranks, and that at and above the level of order the rule of priority does not apply. Some names have also been conserved or rejected, usually to prevent unwanted nomenclatural change.

CLASSIFICATION AND THE ANGIOSPERM PHYLOGENY GROUP In early classifications, plants were usually organised according to their presumed medicinal traits. The first comprehensive herbals of the 16th century provided some accurate circumscriptions but were organised by usefulness rather than similarity or putative relationships. In the mid-18th century, Carolus Linnaeus invented an artificial system for classification of plants based on numbers of flower parts (Figure 6). His ‘sexual system’ described how, for instance ‘six men were in bed with one woman’ (hexandria monogynia) in Allium, Hyacinthus and Hemerocallis, three genera we now know to belong to three families. These characters were useful for identification, but the classification was known to be artificial (unnatural) because other characters, for instance of leaves etc., were not taken into account. Many of these sexual characters evolved in parallel, and thus species were frequently placed together that we now know

8

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are distantly related and vice versa. Linnaeus himself knew that this system had these shortcomings, but he was more interested in an easily understood classification than in placing related species together. The prevailing species concept of the time was that species were unchangeable entities created by God. With the advent of Darwinian evolution and discovery of Mendelian genetics, species concepts changed. For classification, usually extrinsic morphological characters became used to secure a more ‘natural’ classification, but these were often subjectively interpreted characters. Workers such as Cronquist (1981), Takhtajan (1980, 1997) and Thorne (1992) based their classifications on all data available at the time (morphology, anatomy, ontogeny, chemistry etc.), but subjectively filtered the Figure 6. The sexual system of Linnaeus as illustrated by Ehret (1736)

All names are followed by the author name (often abbreviated), which is done to prevent confusion in the cases of similar names or homonyms by various authors. This book deals mostly with the levels above genus; at these higher levels, name confusion is not a big issue. Therefore in this encyclopedia we have omitted these author names because they are not commonly used outside taxonomic publications. We recommend that all scientific journals include author names as full references in their papers, as this links to descriptions and associated data on the species when it was first found.

NAMING PLANTS Taxonomic ranks in plants have standard endings so they can be easily recognised, as for instance an order or family. These endings are as follows: Division: -ophyta, e.g. Equisetophyta (this rank is rarely used) Subdivision: -ophytina, e.g. Equisetophytina (this rank is rarely used) Class: -opsida, e.g. Equisetopsida Subclass: -idae, e.g. Equisetidae Superorder: -anae, e.g. Equisetanae Order: -ales, e.g. Equisetales Suborder: -ineae, e.g. Equisetineae (this rank is rarely used) Family: -aceae, e.g. Equisetaceae Subfamily: -oideae, e.g. Equisetoideae Tribe: -ideae, e.g. Equisetideae Subtribe: -inae, e.g. Equisetinae

All these names are based on the stem of the genus that typifies these ranks. In this case the type genus is Equisetum (stem: Equiset-), which means ‘horse bristle’, the horsetail in English. Genus names and species epithets are always written in italics with the genus name capitalised. The species epithet (the second of the two words that make up the species name) is not capitalised. Below the rank of species there are several additional ranks, mainly subspecies (subsp.), variety (var.) and forma (fo.). It has to be noted that the rule of priority applies only within a rank, not across ranks, and that at and above the level of order the rule of priority does not apply. Some names have also been conserved or rejected, usually to prevent unwanted nomenclatural change.

CLASSIFICATION AND THE ANGIOSPERM PHYLOGENY GROUP In early classifications, plants were usually organised according to their presumed medicinal traits. The first comprehensive herbals of the 16th century provided some accurate circumscriptions but were organised by usefulness rather than similarity or putative relationships. In the mid-18th century, Carolus Linnaeus invented an artificial system for classification of plants based on numbers of flower parts (Figure 6). His ‘sexual system’ described how, for instance ‘six men were in bed with one woman’ (hexandria monogynia) in Allium, Hyacinthus and Hemerocallis, three genera we now know to belong to three families. These characters were useful for identification, but the classification was known to be artificial (unnatural) because other characters, for instance of leaves etc., were not taken into account. Many of these sexual characters evolved in parallel, and thus species were frequently placed together that we now know

8

Christenhusz, Fay & Chase

are distantly related and vice versa. Linnaeus himself knew that this system had these shortcomings, but he was more interested in an easily understood classification than in placing related species together. The prevailing species concept of the time was that species were unchangeable entities created by God. With the advent of Darwinian evolution and discovery of Mendelian genetics, species concepts changed. For classification, usually extrinsic morphological characters became used to secure a more ‘natural’ classification, but these were often subjectively interpreted characters. Workers such as Cronquist (1981), Takhtajan (1980, 1997) and Thorne (1992) based their classifications on all data available at the time (morphology, anatomy, ontogeny, chemistry etc.), but subjectively filtered the Figure 6. The sexual system of Linnaeus as illustrated by Ehret (1736)

All names are followed by the author name (often abbreviated), which is done to prevent confusion in the cases of similar names or homonyms by various authors. This book deals mostly with the levels above genus; at these higher levels, name confusion is not a big issue. Therefore in this encyclopedia we have omitted these author names because they are not commonly used outside taxonomic publications. We recommend that all scientific journals include author names as full references in their papers, as this links to descriptions and associated data on the species when it was first found.

CLASSIFICATION AND THE ANGIOSPERM PHYLOGENY GROUP

Sister species Rapid radiation

Extinction

Speciation

Common ancestor

Figure 7a. Hypothetical visualisation of a phylogenetic tree on a real tree (Callitris glaucophyllum, Cupressaceae)

Sister species

tin on ct i

Speciation

Ex

information to determine which character was most important and should be the basis of classification. These classifications had a great following, but unfortunately ontogenetic data could not always be obtained, and thus parts of these classifications were sometimes still only a matter of speculation. Phylogenetic analysis of scored morphological and ontogenetic characters was sometimes carried out, sometimes also including fossil taxa. This made classifications less subjective, although they were dependent on the interpretation of the characters, and the manner in which they were scored occasionally influenced results. In the late 1980s, the molecular age began, and increasingly greater numbers of DNA sequences could be compared, analysed separately or together with morphological data, resulting in testable, much less subjective classifications. The use of DNA sequences in phylogenetic reconstructions almost entirely removed subjectivity and allowed a better understanding of relationships of morphologically difficult-toplace groups. Relationships of plants are usually visualised by means of a phylogenetic tree. In those based on DNA information, each terminal branch is based on the DNA sequence of an individual plant, which is often considered to represent its species, genus, family or (as in the case below) order. Species that are alive today may have had many extinct relatives, which in a phylogenetic tree will make such species look isolated (Figure 7). Sometimes, when a species-rich clade is sister to a species-poor clade, people tend to read it as if the small clade is “basal” or “primitive”, but this assumption is erroneous. It is a misconception that makes reading a phylogenetic tree problematic. For instance, most modern ferns have evolved as recently as most flowering plant clades, but the ferns are an old lineage and have retained many of the original fern characters. However, ferns are also competitive in modern ecosystems and by no means primitive in all their attributes. The original Angiosperm Phylogeny Group (APG 1998) ushered in a new way of constructing a classification: one based on an explicitly analysed set of data rather than on an intuitive interpretation of available data. Additionally, it was not authored by a single authority, but was based on an informal consensus among many researchers involved in various studies

Rapid radiation

Speciation

Speciation

Figure 7b. Abstract visualisation of evolution based on the same tree

Common ancestor

Plants of the World

9

CLASSIFICATION AND THE ANGIOSPERM PHYLOGENY GROUP of classification at the time. Data were still scant in the late 1990s, and the primary focus of APG was to place families in orders. Family circumscriptions became more important when the first update of the APG classification was proposed (APG II 2003). This classification included the so-called ‘bracketed system’, in which a researcher could either use a broader or narrower circumscription of several families but still follow the APG classification. This flexibility caused confusion and was therefore abolished in APG III (2009). The APG system is now widely established, and most libraries, herbaria, botanical gardens and online resources follow it. Even though most issues are now settled, the discussion about broader or narrower families still continues in some cases, and, as long as monophyletic groups are recognised, this choice is arbitrary. The fourth update of APG resolved some issues that could not be resolved with available data in 2009, and APG IV (2016) focused more on family delimitation than any of the APG systems did before. Due to an emphasis on stability, APG IV does not differ much from APG III. Apart from some minor additions of previously unplaced or misplaced genera, the last two updates of the APG classifications are practically the same. Only in the treatment of Gesneriaceae we have diverged from APG IV as that system left Peltanthera unplaced, and we propose that it is better placed with Calceolariaceae in an expanded Gesneriaceae. For lycopods, ferns and gymnosperms, similar molecular-based classifications have been proposed. Here, we follow those of Christenhusz & Chase (2014) for lycopods and ferns and Christenhusz et al. (2011) for gymnosperms. To the right, we present formal cladograms at the ordinal level, showing relationships between orders and larger groups. We realise that many people find these difficult to read, especially because they are a two-dimensional depiction of a multidimensional phenomenon. Therefore we also provide a less formal ‘tree of life’, in which the orders are placed on their respective branches and the approximate ages of these branches are given (Figures 8 and 9).

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Lycopods

Ferns

Gymnosperms

Angiosperms

Eudicots

Figure 8. Simplified phylogenetic tree showing relationships of the orders of vascular plants.

Algae Mosses Hornworts Liverworts Lycopodiales Isoëtales Selaginellales Ophioglossales Psilotales Equisetales Marattiales Osmundales Hymenophyllales Gleicheniales Schizaeales Salviniales Cyatheales Polypodiales Zamiales Cycadales Ginkgoales Welwitschiales Gnetales Ephedrales Araucariales Pinales Cupressales Amborellales Nymphaeales Austrobaileyales Chloranthales Piperales Canellales Magnoliales Laurales Acorales Alismatales Petrosaviales Dioscoreales Pandanales Liliales Asparagales Arecales Commelinales Zingiberales Poales Ceratophyllales Ranunculales Proteales Trochodendrales Buxales Gunnerales Dilleniales Saxifragales Vitales Zygophyllales Cucurbitales Fagales Fabales Rosales Oxalidales Celastrales Malpighiales Geraniales Myrtales Crossosomatales Picramniales Sapindales Huerteales Malvales Brassicales Santalales Berberidopsidales Caryophyllales Cornales Ericales Icacinales Metteniusales Garryales Vahliales Gentianales Solanales Lamiales Boraginales Aquifoliales Asterales Escalloniales Bruniales Dipsacales Paracryphiales Apiales

Magnoliids

Monocots

Rosids

Asterids

CLASSIFICATION AND THE ANGIOSPERM PHYLOGENY GROUP

EUDICOTS FLOWERING PLANTS

Malpighiales Oxalidales Celastrales

Santalales Ericales

Garryales Icacinales

Zygophyllales Vitales

Caryophyllales

Gentianales

100

Solanales

Fagales Cucurbitales Fagales Geraniales Myrtales Rosales Crossosomatales Huerteales 100 Malvales Brassicales Picramniales Sapindales

Vahliales Dilleniales Asterales Boraginales 115 115 100 Lamiales Saxifragales Escalloniales Aquifoliales Bruniales Gunnerales Cornales 120 Paracryphiales Apiales Berberidopsidales Petrosaviales Alismatales Trochodendrales Dipsacales Buxales 130 Proteales Ranunculales

120 Acorales

140

Ceratophyllales

Magnoliales

MAGNOLIIDS Polypodiales Cyatheales Salviniales Gleicheniales Osmundales

Austrobaileyales 150

145

Nymphaeales

Piperales

Canellales Amborellales Schizaeales Hymenophyllales Marattiales 200

336

Psilotales

155 255

245 370 Seed plants

Selaginellales

Lycopodiales

Equisetales 385 Hornworts Mosses Liverworts 484

GYMNOSPERMS Pinales Cupressales Araucariales Gnetales Welwitschiales Ephedrales Ginkgoales Cycadales

Isoëtales

380

Ophioglossales

FERNS

MONOCOTS

Chloranthales

Laurales

Asparagales Arecales Poales Commelinales Liliales Zingiberales Pandanales Dioscoreales

LYCOPODS

Vascular plants 446 290

379

Figure 9. Visualisation of simplified phylogenetic tree showing relationships of the orders of vascular plants. Numbers indicate the approximate ages of branches in millions of years.

Plants of the World

11

CLASSIFICATION AND THE ANGIOSPERM PHYLOGENY GROUP

Diorama of a forest during the Carboniferous with Cordaites (putative relative of Equisetales) Sigillaria (Isoëtales) and Psaronius (Marattiales). University of Michigan Museum of Natural History, Ann Arbor, USA.

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FOSSIL PLANTS When people think of fossils, dinosaur bones mostly come to mind. Of course skeletons and shells are the hardest part of an animal and are the most likely to become fossilised, but some plants also fossilise well even though they have no skeleton. Their cells have rigid walls of cellulose, so it is more likely that woody structures, seeds and leaves are preserved rather than soft tissues. Most of our knowledge of the history of life on earth is derived from fossils, and they are an important key in understanding evolution and relationships between organisms though so-called ‘missing links’, and fossils are essential for estimating ages of clades. Fossil plants are especially important in estimating past climate by comparing distributions of fossil taxa with the ranges of their extant relatives. Also leaf stomata are often well preserved and can be studied to estimate past CO2 concentrations, an invaluable tool in climate reconstruction and understanding past, present and future climate change. After plants become buried in sediment, the spaces left inside the cell wall are sometimes replaced by inorganic material, usually chert, a fine crystalline quartz. This process is called permineralisation, which most commonly occurs in woody tissues (forming petrified wood), but can also happen in herbaceous cells or porous animal skeletons. Sometimes the dead tissue is dissolved, leaving an imprint of the organic structures in the sediment. These impression fossils are often useful for understanding the shapes of soft tissues that do not permineralise well. Sometimes a residue of carbon from the organism remains in the impression fossil, which is called carbonisation. When this happens on a larger scale, as in the swamps of the Carboniferous, this can form coal or, under higher pressure, oil or diamonds. Rare fossils that preserved or show outlines of soft

parts such as flowers (Figure 10) are always preserved under special conditions, such as rapid burial in fine sediment, absence of oxygen or protection in an enclosed structure formed from chemicals emitted by the fossilising organism. Charcoalified plant parts (partially burned) are also an important type of fossilised material. Spores and pollen often preserve particularly well because they are covered in sporopollenin, a substance that does not easily decay and thus is readily preserved in the fossil record, especially under anaerobic conditions, such as lakebeds and swamps. The age of a certain fossil can be estimated from the particular layer, or stratum, in which it was found. Radioactive decay can also be measured to estimate the age of the sediment, and carbonised fossils can be carbon-dated, more precisely so when they are not too ancient. We do not attempt to provide a full overview of the fossil history of each family, as this is a different discipline and not relevant to the general reader interested in living plants, but where appropriate, we mention the most important fossils used for inferring the evolutionary age of the family or morphological evolution. The most important extinct clades are listed and placed tentatively in the classification above. In the Phylogeny and Evolution sections, we discuss previous and current ideas about the relationships of each family. The main changes in circumscription of these families and genera are also mentioned.

Figure 10 A fossil palm (Sabal sp.), Naturalis, Leiden, the Netherlands

Plants of the World

13

FAMILIES A plant family is composed of one or more genera that share some characters and are monophyletic (i.e. they form an exclusive group, with each being more closely related to others in the group than to plants belonging to another group). The definition of a plant family has varied in the past, and some such as daisies (Asteraceae), umbels (Apiaceae), crucifers (Brassicaceae), orchids (Orchidaceae), grasses (Poaceae) and palms (Arecaceae) have a long history of use with little change in concept over the years, whereas others, such as Scrophulariaceae, Liliaceae and Salicaceae have undergone dramatic changes in the number of genera included and their circumscription. In their current circumscriptions, there are 451 vascular plant families when following the classifications of APG IV (2016), Christenhusz & Chase (2014) and Christenhusz et al. (2014). These encompass an approximate total of c. 300,750 species of

which approximately 180,000 are eudicots, 109,000 are monocots, 10,550 are ferns, 1,290 are lycopods and 1,011 are gymnosperms. The ten largest vascular plant families comprise c. 121,180 species, and there is a big gap between the largest five families and the rest. Orchidaceae are probably the largest vascular family, comprising nearly 9% of botanical diversity, followed closely by Asteraceae. It has to be noted that there are still species being described, and this will result in all these numbers slowly increasing over the coming decades.

The 20 largest vascular plant families Family 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20

Orchidaceae Asteraceae Fabaceae Rubiaceae Poaceae Lamiaceae Euphorbiaceae Myrtaceae Cyperaceae Melastomataceae Apocynaceae Ericaceae Malvaceae Polypodiaceae Acanthaceae Gesneriaceae Piperaceae Brassicaceae Apiaceae Bromeliaceae

Approximate number of species 26,470 24,700 16,020 13,620 11,000 6,800 6,243 5,828 5,500 5,000 4,300 4,250 4,225 4,070 4,000 3,810 3,700 3,628 3,575 3,475

ETYMOLOGY AND COMMON NAMES According to the International Code of Botanical Nomenclature, each family name is based on a genus, the type genus of that particular family (although due to priority, these names can be considered a later synonym of another genus and thus not in current use, e.g. Hydatella is a later name for Trithuria, and although it is the basis for Hydatellaceae, Hydatella is considered a synonym). For each family we have provided the likely origin of the name of the type genus. These scientific names are usually based on Greek or Latin, but they sometimes use another language or are chosen to honour a person or place. Etymology provides some insight into the

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botanical history of naming genera and families, and the construction/meaning of names may help the novice to get to grips with scientific names. For each family, we also provide a common name based either on the type genus or on a well-known representative of the family. As already stated earlier, common names can vary between areas, and therefore these are not stable. Usually the common name of a family is based on common names of representatives found in English language areas, mainly the UK, USA, South Africa or Australia. This of course causes issues with some common names; for instance for Platanaceae, we

decided not to call it the sycamore family because even though sycamore in America is Platanus occidentalis (Platanaceae), a sycamore in England is Acer pseudoplatanus (Sapindaceae) and in East Africa the name is reserved for Ficus sycomorus (Moraceae). So when names cause confusion, we opted for the least confusing option, in this case “plane tree family” for Platanaceae. In cases where no common names are available, we chose a common name derived from the most widely used vernacular name in another language, if reasonably pronounceable in English. In a few cases, we coined a new name, hoping that these will appeal to the user.

FAMILIES A plant family is composed of one or more genera that share some characters and are monophyletic (i.e. they form an exclusive group, with each being more closely related to others in the group than to plants belonging to another group). The definition of a plant family has varied in the past, and some such as daisies (Asteraceae), umbels (Apiaceae), crucifers (Brassicaceae), orchids (Orchidaceae), grasses (Poaceae) and palms (Arecaceae) have a long history of use with little change in concept over the years, whereas others, such as Scrophulariaceae, Liliaceae and Salicaceae have undergone dramatic changes in the number of genera included and their circumscription. In their current circumscriptions, there are 451 vascular plant families when following the classifications of APG IV (2016), Christenhusz & Chase (2014) and Christenhusz et al. (2014). These encompass an approximate total of c. 300,750 species of

which approximately 180,000 are eudicots, 109,000 are monocots, 10,550 are ferns, 1,290 are lycopods and 1,011 are gymnosperms. The ten largest vascular plant families comprise c. 121,180 species, and there is a big gap between the largest five families and the rest. Orchidaceae are probably the largest vascular family, comprising nearly 9% of botanical diversity, followed closely by Asteraceae. It has to be noted that there are still species being described, and this will result in all these numbers slowly increasing over the coming decades.

The 20 largest vascular plant families Family 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20

Orchidaceae Asteraceae Fabaceae Rubiaceae Poaceae Lamiaceae Euphorbiaceae Myrtaceae Cyperaceae Melastomataceae Apocynaceae Ericaceae Malvaceae Polypodiaceae Acanthaceae Gesneriaceae Piperaceae Brassicaceae Apiaceae Bromeliaceae

Approximate number of species 26,470 24,700 16,020 13,620 11,000 6,800 6,243 5,828 5,500 5,000 4,300 4,250 4,225 4,070 4,000 3,810 3,700 3,628 3,575 3,475

ETYMOLOGY AND COMMON NAMES According to the International Code of Botanical Nomenclature, each family name is based on a genus, the type genus of that particular family (although due to priority, these names can be considered a later synonym of another genus and thus not in current use, e.g. Hydatella is a later name for Trithuria, and although it is the basis for Hydatellaceae, Hydatella is considered a synonym). For each family we have provided the likely origin of the name of the type genus. These scientific names are usually based on Greek or Latin, but they sometimes use another language or are chosen to honour a person or place. Etymology provides some insight into the

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botanical history of naming genera and families, and the construction/meaning of names may help the novice to get to grips with scientific names. For each family, we also provide a common name based either on the type genus or on a well-known representative of the family. As already stated earlier, common names can vary between areas, and therefore these are not stable. Usually the common name of a family is based on common names of representatives found in English language areas, mainly the UK, USA, South Africa or Australia. This of course causes issues with some common names; for instance for Platanaceae, we

decided not to call it the sycamore family because even though sycamore in America is Platanus occidentalis (Platanaceae), a sycamore in England is Acer pseudoplatanus (Sapindaceae) and in East Africa the name is reserved for Ficus sycomorus (Moraceae). So when names cause confusion, we opted for the least confusing option, in this case “plane tree family” for Platanaceae. In cases where no common names are available, we chose a common name derived from the most widely used vernacular name in another language, if reasonably pronounceable in English. In a few cases, we coined a new name, hoping that these will appeal to the user.

GENERA In this book we list the accepted genera with estimated numbers of species according to the latest treatments, following the Checklist of Selected Plant Families (http://apps.kew. org/wcsp/home.do) or, when a family is not treated there, other online or printed sources. Of course, as soon as this book is printed, these lists will be outdated: new genera and species will have been described, and new phylogenetic trees will show different configurations forcing reclassifications and inevitable nomenclatural changes. However, we believe that providing generic lists and species numbers will help people in placing genera in the correct family and give them an idea about size, even if it is only an informed estimate. Larger genera (with 100 or more species) are marked in boldface in the lists of genera under each family. The largest genera in the plant world are Astragalus (Fabaceae), Piper (Piperaceae) and Euphorbia (Euphorbiaceae). Segregate or smaller genera have not been widely accepted in these three genera, and therefore they remain large. Delimitation of genera is often based on arbitrarily selected morphological characters, but two options are possible if a genus is found not to be monophyletic: 1) split off one or more new genera to preserve a well-established

genus name for which the species were found to be embedded in another genus (splitting); or 2) enlarge a genus when it is found to be polyphyletic or paraphyletic and include genera found to be embedded in it (lumping), which is what has been done with most of the largest genera in the table (right). We advocate this for some groups in which genera are small and now finely split. This of course depends on the taxonomists working on the group and acceptance of new names by the users of these names. The species numbers for Sedum and Thelypteris given below are those if they are to be taken in their broad sense. Similarly, the large genus Alchemilla (Rosaceae) is embedded in Potentilla (along with several others, such as strawberry, Fragaria), and Potentilla can be divided. However, it may be better to expand it, which would then give rise to a genus that should be included in our list of large genera (right); for this to be formally accepted, many transfers of species from other genera to Potentilla would first be needed. Generic circumscription is a human construct and a matter of stability, historical concepts, morphological, genetic uniformity, and most of all a matter of opinion. Therefore the discussion between ‘lumpers’ and ‘splitters’ will likely be a never-ending story.

The largest genera of vascular plants Number of species

Family

Genus

Fabaceae

Astragalus

c. 2,400

Piperaceae

Piper

c. 2,100

Euphorbiaceae

Euphorbia

1,933

Orchidaceae

Bulbophyllum

1,867

Rubiaceae

Psychotria

1,858

Cyperaceae

Carex

1,829

Begoniaceae

Begonia

1,803

Asteraceae

Senecio

Piperaceae

Peperomia

Orchidaceae

Dendrobium

Orchidaceae

Epidendrum

Solanaceae

Solanum

Euphorbiaceae

Croton

1,186

Myrtaceae

Syzygium

1,136

Aspleniaceae

Thelypteris s.l.

Orchidaceae

Lepanthes

1,085

Fabaceae

Acacia s.s.

1,075

Myrtaceae

Eugenia

Balsaminaceae

Impatiens

1,633 c. 1,600 1,509 1,413 c. 1,300

c. 1,100

1,044 c. 1,000

Ericaceae

Rhododendron

c. 1,000

Melastomataceae

Miconia

c. 1,000

Phyllanthaceae

Phyllanthus

c. 1,000

Rosaceae

Alchemilla

c. 1,000

Crassulaceae

Sedum s.l.

979

Amaryllidaceae

Allium

920

Lamiaceae

Salvia

c. 900

PHYTOGEOGRAPHY Phytogeography is the study of plant distributions, both historical and modern. When distributions and phylogenetic history are known, the current distribution can sometimes be explained. On the basis of georeferenced herbarium specimens, detailed maps can be made of where species have been found, and these data can be used to

make ecological niche models and to predict current, past and future distributions under changing climatic conditions. The maps provided here are not detailed, but for each family we provide their rough native range. Even though these ranges are rough estimates, they are based on known occurrences, and it is possible that occasional

finds of family members outside the given range occur. This may be due to occasional new finds, species naturalised from horticulture or agriculture or perhaps even range changes due to climate change. When possible, the area of largest diversity is provided in the text. These maps are just a general indication of where plants occur and are by no means precise. For

Plants of the World

15

GENERA In this book we list the accepted genera with estimated numbers of species according to the latest treatments, following the Checklist of Selected Plant Families (http://apps.kew. org/wcsp/home.do) or, when a family is not treated there, other online or printed sources. Of course, as soon as this book is printed, these lists will be outdated: new genera and species will have been described, and new phylogenetic trees will show different configurations forcing reclassifications and inevitable nomenclatural changes. However, we believe that providing generic lists and species numbers will help people in placing genera in the correct family and give them an idea about size, even if it is only an informed estimate. Larger genera (with 100 or more species) are marked in boldface in the lists of genera under each family. The largest genera in the plant world are Astragalus (Fabaceae), Piper (Piperaceae) and Euphorbia (Euphorbiaceae). Segregate or smaller genera have not been widely accepted in these three genera, and therefore they remain large. Delimitation of genera is often based on arbitrarily selected morphological characters, but two options are possible if a genus is found not to be monophyletic: 1) split off one or more new genera to preserve a well-established

genus name for which the species were found to be embedded in another genus (splitting); or 2) enlarge a genus when it is found to be polyphyletic or paraphyletic and include genera found to be embedded in it (lumping), which is what has been done with most of the largest genera in the table (right). We advocate this for some groups in which genera are small and now finely split. This of course depends on the taxonomists working on the group and acceptance of new names by the users of these names. The species numbers for Sedum and Thelypteris given below are those if they are to be taken in their broad sense. Similarly, the large genus Alchemilla (Rosaceae) is embedded in Potentilla (along with several others, such as strawberry, Fragaria), and Potentilla can be divided. However, it may be better to expand it, which would then give rise to a genus that should be included in our list of large genera (right); for this to be formally accepted, many transfers of species from other genera to Potentilla would first be needed. Generic circumscription is a human construct and a matter of stability, historical concepts, morphological, genetic uniformity, and most of all a matter of opinion. Therefore the discussion between ‘lumpers’ and ‘splitters’ will likely be a never-ending story.

The largest genera of vascular plants Number of species

Family

Genus

Fabaceae

Astragalus

c. 2,400

Piperaceae

Piper

c. 2,100

Euphorbiaceae

Euphorbia

1,933

Orchidaceae

Bulbophyllum

1,867

Rubiaceae

Psychotria

1,858

Cyperaceae

Carex

1,829

Begoniaceae

Begonia

1,803

Asteraceae

Senecio

Piperaceae

Peperomia

Orchidaceae

Dendrobium

Orchidaceae

Epidendrum

Solanaceae

Solanum

Euphorbiaceae

Croton

1,186

Myrtaceae

Syzygium

1,136

Aspleniaceae

Thelypteris s.l.

Orchidaceae

Lepanthes

1,085

Fabaceae

Acacia s.s.

1,075

Myrtaceae

Eugenia

Balsaminaceae

Impatiens

1,633 c. 1,600 1,509 1,413 c. 1,300

c. 1,100

1,044 c. 1,000

Ericaceae

Rhododendron

c. 1,000

Melastomataceae

Miconia

c. 1,000

Phyllanthaceae

Phyllanthus

c. 1,000

Rosaceae

Alchemilla

c. 1,000

Crassulaceae

Sedum s.l.

979

Amaryllidaceae

Allium

920

Lamiaceae

Salvia

c. 900

PHYTOGEOGRAPHY Phytogeography is the study of plant distributions, both historical and modern. When distributions and phylogenetic history are known, the current distribution can sometimes be explained. On the basis of georeferenced herbarium specimens, detailed maps can be made of where species have been found, and these data can be used to

make ecological niche models and to predict current, past and future distributions under changing climatic conditions. The maps provided here are not detailed, but for each family we provide their rough native range. Even though these ranges are rough estimates, they are based on known occurrences, and it is possible that occasional

finds of family members outside the given range occur. This may be due to occasional new finds, species naturalised from horticulture or agriculture or perhaps even range changes due to climate change. When possible, the area of largest diversity is provided in the text. These maps are just a general indication of where plants occur and are by no means precise. For

Plants of the World

15

PHYTOGEOGRAPHY Global Biodiversity: Species numbers of vascular plants © Barthlott 2014

example, Amborella (Amborellaceae) does not grow everywhere on New Caledonia. It is not uncommon in the upland forest, so the entire island is coloured, even though it is only found in a few places. If one overlays these distribution maps (Figure 11), we would get a map showing the hotspots of family diversity. The main areas are obviously in the tropics, but it should be pointed out that warm temperate areas like southwestern Australia, southern Africa and southern China also have remarkably diverse floras. This phylogenetic diversity agrees fairly well with the known hotspots of biodiversity (Myers et al. 2000), and these areas should be given priority for botanical conservation. Phylogenetic diversity is important, and thus when a family is restricted to a small area it is important that this area is considered for protection. Since such a family is unlikely to have close relatives, if it goes extinct, an entire lineage would be lost.

Diversity zones (DZ), number of vascular plant species per 10,000 km² DZ 1 ( 5000) Barthlott, W., Rafiqpoor, M.D., & Mutke, J. 2014 based on former publication starting with Barthlott, W., Lauer, W. & Placke, A. 1996

Figure 11. Overlay of family distributions, showing the areas of the world with the greatest diversity of vascular plant families.

ECONOMIC BOTANY Plants are the foundation of civilisation. We need the oxygen and clean air that plants produce, and we need fruits, vegetables, other foods, medicinal compounds and fibre, all of these are clear. What few people also realise is that most of our culture and economy is based on plants, the main exception being wind, wave and solar energy generation, the last imitating the capacity of plants to harvest energy from the sun. Plants underlie every part of our economy; plants form the basis of agriculture, banking, building, education, fashion, fishery, fossil fuels, health care, industry, medicine, trade, transportation etc. Botany should receive a much more central role in general research and research funding than it currently is given. Considering how much we still do not know about these organisms that make the world function, there is a great need to study the biodiversity of this planet, and plant diversity should be the highest priority.

16

Christenhusz, Fay & Chase

This book provides an overview of plant diversity on Earth, and for each family we provide a list of some economic uses, showing the diversity of products that different plant groups provide humans, including food (cereals, fruit, vegetables, nuts, tubers, grains), animal fodder (Figure 12), medicines, perfumes, oils, dyes, ornamental plants, timber, fibre, clothes and paper. We focus mainly on the common foods and crops, but also include products that are still harvested from the wild. Even though the enumeration is fairly exhaustive, we omit many medicinal plants simply because there are so many, particularly in Indian and Chinese traditional medicines, and there are other good books that focus on traditional medicinal usage of plants. We nevertheless hope to illustrate the great diversity of uses and incredible economic importance of botany, hopefully making plants better understood and more valued by the wider public. Plants should be studied, valued and loved.

Figure 12. Humans have altered their landscape for millennia.

Right: Fruit and vegetable market in Bogota, Colombia, showing a wide diversity of plant products available to humans

PHYTOGEOGRAPHY Global Biodiversity: Species numbers of vascular plants © Barthlott 2014

example, Amborella (Amborellaceae) does not grow everywhere on New Caledonia. It is not uncommon in the upland forest, so the entire island is coloured, even though it is only found in a few places. If one overlays these distribution maps (Figure 11), we would get a map showing the hotspots of family diversity. The main areas are obviously in the tropics, but it should be pointed out that warm temperate areas like southwestern Australia, southern Africa and southern China also have remarkably diverse floras. This phylogenetic diversity agrees fairly well with the known hotspots of biodiversity (Myers et al. 2000), and these areas should be given priority for botanical conservation. Phylogenetic diversity is important, and thus when a family is restricted to a small area it is important that this area is considered for protection. Since such a family is unlikely to have close relatives, if it goes extinct, an entire lineage would be lost.

Diversity zones (DZ), number of vascular plant species per 10,000 km² DZ 1 ( 5000) Barthlott, W., Rafiqpoor, M.D., & Mutke, J. 2014 based on former publication starting with Barthlott, W., Lauer, W. & Placke, A. 1996

Figure 11. Overlay of family distributions, showing the areas of the world with the greatest diversity of vascular plant families.

ECONOMIC BOTANY Plants are the foundation of civilisation. We need the oxygen and clean air that plants produce, and we need fruits, vegetables, other foods, medicinal compounds and fibre, all of these are clear. What few people also realise is that most of our culture and economy is based on plants, the main exception being wind, wave and solar energy generation, the last imitating the capacity of plants to harvest energy from the sun. Plants underlie every part of our economy; plants form the basis of agriculture, banking, building, education, fashion, fishery, fossil fuels, health care, industry, medicine, trade, transportation etc. Botany should receive a much more central role in general research and research funding than it currently is given. Considering how much we still do not know about these organisms that make the world function, there is a great need to study the biodiversity of this planet, and plant diversity should be the highest priority.

16

Christenhusz, Fay & Chase

This book provides an overview of plant diversity on Earth, and for each family we provide a list of some economic uses, showing the diversity of products that different plant groups provide humans, including food (cereals, fruit, vegetables, nuts, tubers, grains), animal fodder (Figure 12), medicines, perfumes, oils, dyes, ornamental plants, timber, fibre, clothes and paper. We focus mainly on the common foods and crops, but also include products that are still harvested from the wild. Even though the enumeration is fairly exhaustive, we omit many medicinal plants simply because there are so many, particularly in Indian and Chinese traditional medicines, and there are other good books that focus on traditional medicinal usage of plants. We nevertheless hope to illustrate the great diversity of uses and incredible economic importance of botany, hopefully making plants better understood and more valued by the wider public. Plants should be studied, valued and loved.

Figure 12. Humans have altered their landscape for millennia.

Right: Fruit and vegetable market in Bogota, Colombia, showing a wide diversity of plant products available to humans

LYCOPODS (LYCOPODIIDAE) Lycopods or clubmosses are the sister lineage to all other vascular plants (ferns plus seed plants) and are among the oldest lineages of living plants. Extant species are, however, highly divergent from the early members of this group. They were diverse in the Carboniferous, when some species formed large trees dominating the ancient forests. Modern lycopods are all low-growing herbaceous plants, with some scrambling Selaginella reaching the height of only a few metres. Isoëtes retains some of this anatomical diversity and has secondary (woody) growth in its short stem. Like ferns, lycopods have a clearly alternating life cycle, with sporophytes being the large plants we commonly observe. These make spores from which gametophytes grow upon germination and produce free-swimming sperm. This makes these plants dependent on water, although many sporophytes have evolved strategies to deal with drought. Sporophytes have roots and stems that

bear spirally arranged or whorled leaves called microphylls, served only by a single vein (except for a few Selaginella species). Lycopods differ from ferns and the seed plants in having microphylls instead of macrophylls (leaves supplied with several veins). Stems are usually protostelic or sometimes polystelic and sporangia are either born on a microphyll or are associated with one. Often placed among ‘fern allies’, the correct name for this lineage is lycopodiophytes or lycopods, not ‘lycophytes’ as often erroneously used. Due to their life-history strategy, which is like that of the ferns, and their relatively inconspicuous nature, most people think of them as ‘fern allies’, but they are equally closely related to the seed plants. General references: Ambrose BA. 2013. The morphology and development of lycophytes. Annual Plant Review 45: 91–114. Boyce CK. 2005. The evolutionary history of roots and leaves. pp. 479–499 in Holbrook

NM, Zwienieckl MA (eds). Vascular transport in plants. Elsevier, Amsterdam. Christenhusz MJM, Zhang X-C, Schneider H. 2011. A linear sequence of extant families and genera of lycophytes and ferns. Phytotaxa 19: 7–54. Horn K, Franke T, Unterseher M, Schnitter M, Beenken L. 2013. Morphological and molecular analysis of fungal endophytes of achlorophyllous gametophytes of Diphasiastrum alpinum (Lycopodiaceae). American Journal of Botany 100: 2158–2174. McLoughlin S, Jansson I-M, Vajda V. 2014. Megaspore and microfossil assemblages reveal diverse herbaceous lycophytes in the Australian Early Jurassic flora. Grana 53: 22–53. Ranker TA, Hauf ler CH. 2008. Biology and evolution of ferns and lycophytes. Cambridge University Press, Cambridge. Renzaglia KS, Whittier DP. 2013. Microanatomy of the placenta of Lycopodium obscurum: novel design in an underground embryo. Annals of Botany 112: 1083–1088.

LYCOPODIALES The order is comprised of a single family, a group of herbaceous plants known collectively as the clubmosses and firmosses, all with dichotomously branching stems. They have exosporic gametophytes like those of ferns.

1. LYCOPODIACEAE Clubmoss family

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These plants are erect or pendulous, terrestrial or epiphytic, homosporous herbs. Stems are dichotomously branched and protostelic. Microphylls (simple leaves with a single unbranched vein) are spirally arranged or whorled, sometimes decussate. All leaves are similar or those bearing sporangia differ from the sterile ones; the latter can be aggregated in distinct strobili (‘cones’). Sporangia are kidney-shaped or globular, dehiscing by a slit, and are formed singularly in the leaf

axils. Spores are trilete and subglobose to tetrahedral. Gametophytes are tuberous, mycoheterotrophic when subterranean or photosynthetic when surface-living. Distribution: A cosmopolitan family, but absent from arid regions. Phylogeny and evolution: Lycopodiaceae have no close affinity with any other group of plants; even the relationship with

LYCOPODIALES

LYCOPODS

Selaginellaceae and Isoëtaceae is ancient. Fossil Lycopodiaceae cannot be referred with certainty to extant groups, generally due to their poor preservation. The group dates back to at least the Carboniferous when tree-like members of this lineage thrived and dominated the terrestrial sphere. The extant members of the family form three (to five) clades corresponding to the genera accepted below. Some authors prefer to divide these lineages further, resulting in up to 14 genera, but many of these are difficult to distinguish morphologically. The peculiar Huperzia drummondii (formerly Phylloglossum drummondii) differs in having a subterranean tuber with a rosette of leaves and a single strobilus on a naked peduncle. This morphology is an adaptation to the seasonally dry region in its native Australia, but otherwise it fits in the genus Huperzia where it is now placed.

Huperzia drummondii, Western Australia [1]

Genera and species: Lycopodiaceae consist of three genera with c. 400 species: Huperzia (c. 300), Lycopodiella (c. 40) and Lycopodium (c. 40). Uses: Due to their high flammability, the oil-rich spores of stag’s-horn clubmoss (Lycopodium clavatum) and related species are harvested and sold as ‘lycopodium powder’. When mixed with air it creates an explosive mixture, which is widely used in special effects in the film industry. It was also previously used as a fine dusting on latex products such as condoms and surgical gloves, as a coating of metal moulds to prevent metal from sticking to them when casting the iron, in pharmaceuticals as a pill coating and as a cosmetic powder in make-up. Exposure to Lycopodium spores may cause allergic

Huperzia crassa, Ecuador [1]

Lycopodiella torta, Guadeloupe [1]

Huperzia ribourtii, Tahiti [1]

reactions ranging from mild dermatitis to severe asthma, so its uses involving human contact such as cosmetics have largely disappeared. Spores of Alpine clubmoss (Lycopodium alpinum) have been used in Scandinavia to produce a pale yellow dye in combination with twigs of bog whortleberry (Vaccinium uliginosum, Ericaceae). Several Lycopodium species have been used to weave mats, hats, bags and fish traps. Etymology: Lycopodium is composed of the Greek λύκος (lykos), wolf and ποδιών ( podion), feet, referring to the fuzzy, leafclad branches. Hence, the common name, lycopods (‘wolf claws’ is the translation of the common name in many other languages), for the whole group is appropriate, whereas lycophytes (wolf plants) is not.

Huperzia sieberiana, Guadeloupe [1]

Lycopodiella inundata, Twickel, the Netherlands [1]

Plants of the World

19

ISOËTALES

LYCOPODS

ISOËTALES This order with secondary growth is considered to be sister to the fossil Lepidodendrales, which were giant trees during the Carboniferous. These together are sister to the strictly herbaceous Selaginellales, with which they share heterospory (two sizes of spores) and endosporic gametophytes.

2. ISOËTACEAE Quillwort family

These aquatic or terrestrial heterosporous plants are evergreen or deciduous. Their woody stems (rhizomes) are covered with irregular ‘bark’ from which bulbils often develop. Leaves are spirally arranged, needle-like, filiform, flat or terete, forming a rosette or a tuft. The vascular bundle in the leaf is surrounded by four air canals. Ligules arise from a sac at the leaf base, above the sporangium. Sporangia are globose to ovoid

and are formed above the leaf base and have no dehiscence mechanism. Spores are of two kinds (heterosporous) and are usually formed in separate sporangia. Megaspores are trilete and variously ornamented, whereas microspores are monolete and patterned. Gametophytes are formed within the megaspores (endosporic), which are released and thus considered to be free-living. Microspores produce sperm only. Distribution: Isoëtaceae have a global distribution. They are usually found in clean, low-nutrient (oligotrophic) lakes, streams and ephemeral pools or are terrestrial in humid alpine vegetation. Phylogeny and evolution: The genus Isoëtes forms two clades, one including only two Andean terrestrial species (subgenus Stylites), which differ in their erect stems. Even though most species are aquatic, many

Isoëtes lacustris from C. Johnson (1856) The Fern Allies: a supplement to the Ferns of Great Britain, London, plate 13.

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Christenhusz, Fay & Chase

occur in temporary bodies of water, surviving the dry periods as dormant corms. Fossils attributable to Isoëtes have been found in the Triassic (as Isoëtites), many of which are described from spores only. Genera and species: Isoëtaceae include the single genus Isoëtes with c. 140 species. Uses: The corms of some species are consumed by birds, fish, muskrats and pigs. They contain oils and starch and are not poisonous, but do not have a flavour pleasant enough to be worthy of human consumption. Etymology: Isoëtes is derived from the Greek ίσος (isos), equal, and ετήσ (etes), yearly, meaning equal at all seasons of the year, referring to some evergreen species. The diacritical sign is used to indicate that the o and e are to be pronounced as separate vowels.

Isoëtes drummondii, Perth, Western Australia [2]

SELAGINELLALES

LYCOPODS

SELAGINELLALES This order is comprised of a single family, which previously had been thought to be more closely related to Lycopodiaceae (based on their shared primary growth), but they are instead more closely related to Isoëtales, with which they share heterospory and endosporic gametophytes.

3. SELAGINELLACEAE Spikemoss family

These terrestrial, rarely epiphytic, perennial, heterosporous plants have forked roots (rhizophores). Their main stems are erect or prostrate and not distinguished into rhizomes, but some species with erect branches (pseudofronds) spread by creeping stems. The microphylls (leaves) are spirally arranged, minute, with a ligule, and are all similar or of two kinds (then arranged into four ranks). Fertile leaves are leaf-like and aggregated Selaginella selaginoides, Lake District, UK [3]

in terminal strobili (‘cones’). Sporangia are stalked, placed on the upper surface of fertile leaves, just above the ligule. Spores are of two kinds (heterosporous): megaspores are variously shaped and ornamented, trilete, about four per sporangium, whereas microspores are globose-ellipsoid, variously ornamented, trilete and over 100 per sporangium. Distribution: Spikemosses are distributed worldwide, but with their highest diversity in the tropics. A few species occur in the Arctic, and some can even be found in desert areas, where they are “resurrection plants”: plants that dry to within a small percentage of their fresh weight, but then revive and grow again once provided with water. Phylogeny and evolution: Among arborescent lycopodiophytes of the Carboniferous, some heterosporous herbaceous plants gave rise to Selaginellaceae. The morphogenus

Selaginella lepidophylla, Mexico [3]

Selaginella flabellata, Guadeloupe [3]

Selaginella willdenowii with iridescent leaves, Singapore [3]

Pseudodendron, a common fossil in the Carboniferous that shares some characters with Sigillaria, is now regarded as a species of Selaginellaceae, but the majority of fossils from this family have been described from Cretaceous and Tertiary megaspores. The genus has been divided into five subgenera, but molecular studies have not corroborated these. The DNA markers (plastid genes) that have been used thus far have unusually high substitution rates in this genus, which may impede the reliability of the phylogenetic results. Selaginella moellendorfii has the smallest genome measured so far in vascular plants. A few species have more complex venation but are derived from a group with simple-veined microphylls. Therefore the macrophyll condition evolved independently several (at least two) times. Genera and species: Selaginellaceae consist of the single genus, Selaginella, with c. 750 species. Uses: Some Selaginella species are grown as ornamentals, most notably S. uncinata and S. willdenowii, both with remarkable iridescent leaves. Selaginella lepidophylla is sold bare-root in its dry state as ‘Rose of Jericho’ (although being native to Mexico). This species can be resuscitated when placed in water (similar to Anastatica, Brassicaceae, from the Middle East). Young shoots of S. tamariscina are cooked and eaten in East Asia. Etymology: Selaginella is the diminutive form of selago, Latin for a plant resembling savin (Juniperus sabina). The genus Selago is currently in use for a genus of Plantaginaceae; it also is the epithet of the fir clubmoss (Huperzia selago, Lycopodiaceae), which has some general resemblance to the type species of Selaginella, club spikemoss (Selaginella selaginoides), which is probably how the generic name originated. Plants of the World

21

FERNS Ferns are vascular plants that lack f lowers and are remarkable among plants in having two alternating freeliving generations, called gametophytes and sporophytes. Mosses, gymnosperms and angiosperms (seed plants) also have alternating generations, but these are not both free-living. In mosses and liverworts, sporophytes often lack chlorophyll and are then parasitic on free-living gametophytes. By contrast, the reduced gametophytes of seed plants are dependent (parasitic) on the sporophytes; they are present but never released into the environment. Lycopods have a life cycle that is similar to ferns and were therefore often included in the ‘fern-allies’ together with a number of other groups that are now known to be ferns (e.g. Equisetaceae, Psilotaceae and Ophioglossaceae). Lycopods differ from ferns in having simple one-veined leaves called microphylls, instead of the more complex types (macrophylls) found in ferns. In ferns and lycopods, gametophytes are free-living, although they may be subterrean and provided with

Gametophytes (arrow) and young sporophytes of Danaea geniculata (Marattiaceae) on a damp forest bank near Tapirai, Brazil

22

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carbohydrates through a mycorrhizal (fungal) association. They grow from a spore and are usually reduced thalloid structures, dependent on a humid environment due to the lack of true roots and their thin, flat body. They usually resemble a liverwort (a thallus) on which the gametangia, or gameteproducing organs, are produced (female archegonia and male antheridia). On the surface of the gametophyte, the archegonia have a female cell that produces an egg, and the antheridia produce free-swimming f lagellate sperms; most gametophytes are bisexual and others unisexual. When sufficient water is available, the sperm swims into the archegonia, and after fertilisation a sporophyte develops, leaving the gametophyte to wither away. When suitable conditions for fertilisation are not present, gametophytes may live for a long time and even reproduce asexually, as in some species of Hymenophyllaceae and Pteridaceae that have persisted for centuries or even millennia outside their ideal climatic region. Some species have tuberous gametophytes that lack chlorophyll, live underground and take all their nutrients from fungi. Sporophytes are the plants everyone generally knows as ‘ferns’. These are usually large complex vascular plants that produce spores. Spores are formed in groups called sporangia. In earlybranching ferns (families 4 to 7) sporangia develop from a group of cells. These are often called ‘eusporangiate ferns’, a term that is better avoided because it is simply a descriptive term referring to all groups that are not leptosporangiate; the latter group of ferns are sister to one family of eusporangiate ferns, Osmundaceae. Leptosporangiate ferns are all classified in subclass Polypodiidae and have sporangia that are formed from a single

cell. Sporangia are normally grouped in a sorus, which in most leptosporangiate ferns is covered by a scale-like structure called the indusium. Often sporangia are surrounded by an annulus, a structure that aids in ejecting the spores due to it drying unevenly and rupturing he sporangium wall. Leptosporangiate ferns comprise the vast majority of extant fern species. The oldest fern fossils are found in Carboniferous deposits, when the lineage soon became dominant. They, with lycopods, fixed carbon in fossil oiland coal-rich deposits, which are now mined for energy, causing an increase of carbon in the modern atmosphere, resulting in a greenhouse effect and a changing climate, similarly to how these plants changed the climate when they fixed the atmospheric carbon into the sediment several hundred million years ago. The rise of angiosperms during the Cretaceous is often portrayed as causing a dramatic decline of fern and gymnosperm lineages. However, most modern lineages of ferns show an increase in diversity in response to the increase in habitat diversity created by the diversification and formation of angiosperm-dominated rainforests. For other groups of ferns and fernlike plants, those that produced large forest trees, a decline associated with the rise of the seed plants, especially the angiosperms, may in fact be the case. Because ferns have neither flowers nor seeds, numerous legends surrounded the reproduction of ferns. In the Middle Ages, people believed that fern seeds existed, but that they were invisible and were supposed to give the bearer magical powers, especially invisibility. Seeds only develop on the longest day of the year when they would be difficult to harvest because the devil

FERNS

would, of course, want these powers of invisibility. For the same reason, ferns were considered sacred by early Celtic and Germanic peoples. How to collect fern seeds? You could probably try to shoot an arrow into the sun and if hit, drops of blood would fall on a fern and turn into fern seed. A dozen pewter plates could also serve to catch fern seed, but if pewter plates were not available, a white sheet or even a white napkin might do the trick as well, as long as you were in the right frame of mind. Of course, no one ever saw ‘fern seeds’. These and many other legends arose around the gathering of fern seeds, but it was not until the 18th and early 19th century that germination of fern spores, development and fertilisation of gametophytes and development of sporophytes were discovered. This late discovery of the sexual system of ferns resulted in a poor understanding of the relationships among ferns. In the early days they were generally classified on the basis of their soral structures, but it was soon found that this was artificial and other characters such as stem and leaf anatomy had to be employed. With the dawning of the molecular age in the 1990s, DNA sequences could be compared and ferns were reclassified. The classification of ferns has long suffered due to a lack of consensus as to what constitutes a family comparable to those of the seed plants, and family concepts in ferns have long been unstable and subject to great debate. Here we follow a recent classification of ferns (Christenhusz & Chase 2014). The two major lineages in the ‘eupolypods’ are treated as single large families to prevent recognition of numerous monogeneric families. The earlier classifications of Smith et al. (2006) and Christenhusz et al. (2011) treated eupolypods in a number of small families, which have found some acceptance and are preferred by some, but there has been resistance in following the smaller families segregated

from Woodsiaceae and Dryopteridaceae due to polyphyly of these lineages. However, these families are treated here fully as subfamilies, so that both systems can be applied if preferred. One issue of the system used here is that Aspleniaceae are difficult to define with the inclusion of Thelypteridoideae. They can only be defined now by having two vascular bundles in the petiole, even though the indusium placement also may be a synapomorphy. Expanded Polypodiaceae are problematic due to the inclusion of Hypodematioideae that also have two vascular bundles (and are thus similar to Aspleniaceae), but molecular studies place Hypodematioideae near the basal node of Polypodiaceae s.l., and could possibly be maintained separate if synapomorphies are required. The larger families are, however, in line with the currently widely accepted broad concept of Pteridaceae, which is similarly difficult to define morphologically, but is now widely accepted. Where family limits are drawn is a matter of convention and taste, and time will tell which system users will find easiest to apply. We hope that this encyclopedia will shed light on how ferns are interrelated and showcase the fantastic diversity of this unusual group of plants. With an estimated 11,000 species in 20 families, ferns make up only 2% of vascular plant species. Occurring worldwide, they are most diverse in the wet subtropics and tropical mountains at middle elevations. General references: Bower FO. 1923–1928. The ferns, vols. 1–3. Cambridge University Press, Cambridge. Boyce CK. 2005. Patterns of segregation and convergence in the evolution of fern and seed plant leaf morphologies. Paleobiology 31: 117–140. Camus GM, Gibby M, Johns RJ (eds). 1995. Pteridology in perspective. Kew Publishing, Richmond. Christenhusz MJM, Chase MW. 2014. Trends and concepts in fern classification. Annals of Botany 113: 571–594.

Lehtonen S. 2011. Towards resolving the complete fern tree of life. PLoS One 6: e24851. Manton I. 1958. Chromosomes and fern phylogeny with special reference to Pteridaceae. Journal of the Linnean Society, Botany 56: 73–92. Ranker TA, Haufler CH. (eds). 2008. Biology and evolution of ferns and lycophytes. Cambridge University Press, Cambridge. Schneider H. 2013. Evolutionary morphology of ferns (monilophytes). Annual Plant Reviews 45: 115–140. Schneider H, Schuettpelz E, Pryer KM, Cranfill R, Magallón S, Lupia R. 2004. Ferns diversified in the shadow of angiosperms. Nature 428: 553–557. Tryon RM, Tryon AF. Ferns and allied plants with special reference to tropical America. Springer, New York. Verdoorn F (ed). 1938. Manual of pteridology. Nijhof, The Hague.

Thelypteris hydrophila crozier showing pneumatophores, Guadeloupe

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EQUISETALES

FERNS

EQUISETALES This order formerly included a number of early fossil taxa like the giant Calamites trees, but it is now believed that modern Equisetales are more closely related to ferns, whereas most ancient fossils probably formed a lineage of their own called the Sphenophytes, although equisetalean fossils were also dominant in the Carboniferous and Devonian. Equisetales are easily recognised by their jointed, leafless stems and terminal strobili.

4. EQUISETACEAE Horsetail family

(elaters), which aid dispersal. The gametophytes are green and live on the soil surface, and male gametes are free-swimming with several flagellae, whereas female gametes are sessile on the gametophyte. Distribution: Equisetaceae mostly occur in the temperate Northern Hemisphere and South America, but one species extends into the Old World tropics. Some species are naturalised as agricultural weeds, especially in the temperate areas.

Horsetails are herbaceous terrestrial plants with hollow stems and underground hollow rhizomes called stolons. The leaves are reduced to sheaths that surround the nodes. Typically in most species, stems branch regularly in whorls around the base of the sheaths, but irregular branching and no branching also frequently occur. The spores are formed in sporangia that form on umbrella-like stalked structures that are organised in cone-shaped strobili (‘cones’) on the ends of otherwise vegetative branches, or, in some species, on separate strictly strobilus-bearing non-green shoots. The spores are green and numerous (> 1,000 per sporangium) and have several ‘legs’

Equisetum myriochaetum, Guatemala [4]

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Phylogeny and evolution: The ancestors of horsetails were dominant trees in the vast swamp-forests during the Carboniferous and Devonian periods. Only a single genus remains of this formerly diverse group of plants, and it has been suggested that it is the oldest genus of extant vascular plants. Because of its ancient origin and the lack of characters comparable with other vascular spore-bearing plants, it has often been treated as a class on its own or grouped with Psilotaceae and lycopods as ‘fern allies’. Molecular evidence places the family on a long branch sister to Ophioglos-

Equisetum arvense, Helsinki Botanical Garden, Finland [4]

saceae+Psilotaceae with poor support. It is nevertheless part of the fern clade. Genera and species: A family composed of a single isolated genus, Equisetum, with c. 20 species, hybridisation between many species blurs their delimitation. Uses: Because of the high concentration of silicates, the plants are poisonous in large quantities, but young shoots are consumed in some traditional societies, usually after a complicated preparation process. Marestail (Equisetum arvense) has been used as a diuretic in Europe, but there is little scientific evidence for its effectiveness. It may, however, be a good source of antioxidants. The young stalks have been eaten as a vegetable since Roman times, and some species (e.g. E. arvense, E. laevigatum) were used as food by native Americans. Strobili of E. braunii are reported to be juicy and sweet. Field horsetail (Equisetum arvense) can be a nuisance as a garden weed in Europe and North America and, as an introduction, in South America, Australia and New Zealand. American scouring rush (E. praealtum;

Equisetum bogotense, Ecuador [4]

OPHIOGLOSSALES

FERNS

Botrychium lunaria, Scotland, UK [5]

Botrychium virginianum, Michigan, USA [5]

marketed as E. ‘ japonicum’) and E. scirpoides are sometimes cultivated as pond-margin ornamentals. Like most horsetails, they prefer wet sandy soils. The stems of European scouring rush, Equisetum hyemale, are loaded with silicates

Ophioglossum vulgatum, private garden, A new species of Ophioglossum Kingston upon Thames, Surrey, UK [5] from New Caledonia [5]

and were used historically as an abrasive for scrubbing pots and polishing wood. Equisetum arvense can also be used as a source of green dye, whereas wood horsetail (E. sylvaticum) is used in Scandinavia to produce a grey-yellow dye.

Etymology: Equisetum is derived from the Latin equus, horse, and seta, bristle, in reference to the coarse black roots of the type species, Equisetum fluviatile, that resemble the tail of a horse.

OPHIOGLOSSALES Even though there is practically no fossil record for this order, molecular clock studies suggest this order diverged c. 160 million years ago. The order is composed of the single family Ophioglossaceae, which some authors in the past have not considered to be closely related to ferns, thanks largely to their non-circinnate vernation.

5. OPHIOGLOSSACEAE Adder’s-tongue family

These terrestrial or epiphytic ferns are usually small (rarely larger than 30 cm) and fleshy with a nodding vernation (not rolled as usual in ferns). Rhizomes and petioles are succulent and have secondary (woody) growth, and roots lack root hairs. Leaves emerge singly (or a few) per growing season and are usually divided in a sterile leaf-like part and a basally or centrally attached non-leafy fertile portion (called the sporophore). Venation of the leaves is free in species with divided

blades and reticulate in simple-leaved species. Sporangia are composed of many cells (eusporangiate), globose and marginal or terminal. They contain thousands of spores and because they lack an annulus, the sporangia open along a lateral or vertical line. The spores are globose-tetrahedral and trilete. Gametophytes are tuberous, subterranean, fleshy and achlorophyllous (they are mycoheterotrophic). Distribution: Ophioglossaceae have a nearly worldwide distribution but are excluded from some of the driest habitats. Phylogeny and evolution: Ophioglossaceae stand alone morphologically, but molecular results indicate a relationship with the equally peculiar Psilotaceae. Both families lack root hairs and have similar mycoheterotrophic gametophytes. Morphological studies have suggested a relationship to the extinct lineage of progymnosperms, but there is no fossil evidence to support this. In fact, despite the

presumed ancient origin of the family, few fossils of Ophioglossaceae are known. Genera and species: Ophioglossaceae consist of four genera and c. 80 species: Botrychium (c. 50), Helminthostachys (1), Mankyua (1) and Ophioglossum (c. 30). Uses: Moonwort (Botrychium lunaria) has a long tradition as a herb to treat wounds, and several other Botrychium and Ophioglossum species are also used for this purpose. Young shoots and leaves of Botrychium lunaria, Helminthostachys zeylanica and Ophioglossum vulgatum are sometimes eaten as vegetables in Asia. The young unexpanded shoots of Botrychium australe was previously consumed by Maoris in New Zealand. Etymology: Ophioglossum is derived from the Greek, όφις (ofis), a snake and γλώσσα (glossa), tongue, in reference to the tongueshaped fertile parts of the leaf. Plants of the World

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PSILOTALES

FERNS

PSILOTALES In the past, early land plants with similar bifurcating branches were included here, but these (e.g. Rhynia, Psilophyton) are now known not to be related, a case of extreme convergence. Psilotales were formerly placed among lycopods as they have leaves that are simple, resembling microphylls. Nevertheless they are an ancient plant lineage based on a molecular clock, but the order has scanty fossil evidence and estimates are therefore fairly uncertain. They include the single extant family Psilotaceae and are distantly related to Ophioglossales, with which they share some morphological characters. Distribution: The family is pantropical to warm-temperate, but absent from dry areas. They extend northwards into the southern USA, southwestern Europe and Japan and southwards to New Zealand (Psilotum nudum). The greatest diversity of Tmesipteris is in Australasia and Pacific islands, where it occurs almost exclusively on treefern trunks. Psilotum can be terrestrial, epiphytic or epilithic.

6. PSILOTACEAE Whisk-fern family

These are epiphytic or terrestrial plants without roots. Their rootless rhizomes are fleshy and forked. The stems are usually also forked in twos (dichotomously branched), but are poorly or unbranched in some taxa. Their scale-like leaves have (or lack) a single central vein and therefore resemble microphylls. The sporangia are large and lack an annulus. Sporangia are often fused with two or three together to form a synangium, which appears to be borne on the adaxial side of a forked leaf. The spores are reniform and monolete, and there are > 1,000 per sporangium. The gametophytes are tuberous, subterranean, achlorophyllous and mycoheterotrophic.

Psilotum nudum, Australian National Botanic Gardens, Canberra, Australia [6]

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Phylogeny and evolution: Because of the reduced leaves, the simple dichotomous branching and the protostelic rhizomes that lack roots, Psilotum was often considered to be a “living fossil”, a descendant of the earliest land plants such as the fossil Rhynia (or other Psilotophyta). Because of their microphyll-like leaves they have in the past been associated with lycopods. Due to molecular studies, it is now known with certainty that this resemblance is superficial and that extant Psilotaceae and fossil Psilotophytaceae are not related. Psilotaceae belong to the fern lineage, where they are generally placed as the sister to Ophioglossaceae. The resemblance with that family is maybe not obvious at first, but the similarity in rhizome

Psilotum nudum, Réunion [6]

structure, absence of roots and mycoheterotrophic gametophytes with multiflagellate sperm cells (antherozoids) make Psilotaceae/Ophioglossaceae a good morphological entity. There is little known of these groups in the fossil record. Devonian fossils previously attributed to this lineage are not related to this family. Some species have large genomes, among the largest of any organism (but see also Melanthiaceae). Genera and species: Psilotaceae consist of two genera with a dozen species: Psilotum (2) and Tmesipteris (c. 10). Uses: Spores of Psilotum nudum were collected and used by Hawaiians and Polynesians as talcum powder applied under the loincloth to prevent chafing. It was a sacred plant in Japan during the 17th century, resulting in a great horticultural interest and the development of over 100 cultivars, many of which are still grown in bonsai collections. Etymology: Psilotum is derived from Greek ψηλός (psilos), bare, in reference to the naked stems of Psilotum nudum.

Tmesipteris ovata, New South Wales, Australia [6]

Tmesipteris vieillardii, New Caledonia [6]

MARATTIALES

FERNS

MARATTIALES This is an ancient lineage of ferns and includes the bulk of early fern fossils, such as Psaronius and Asterotheca (fossil Asterothecaceae), which were tall tree-like ferns. Modern Marattiales are easily recognised by their fleshy leaves that arise from succulent or papery outgrowths along the rhizome and their sporangia that are fused into complex synangia.

Angiopteris madagascariensis, Seychelles, with Michael Fay for scale [7]

7. MARATTIACEAE King-fern family

These sometimes enormous, mostly terrestrial ferns have mucilage canals in all their parts. They have large fleshy roots and fleshy rhizomes that are short and upright or creeping and elongate, sometimes globose. The rhizomes bear f leshy or papery, starchy stipule-like outgrowths at the base of leaf insertions that often bear adventitious buds from which new plants can grow. Leaves are usually large, fleshy or leathery and one- to four-times pinnate or palmate, rarely simple. The petioles and rachises have swollen nodes (pulvini) and stems, blades and rhizomes are covered with peltate scales. Lenticels are scattered along petioles and rachises. Their sporangia are fused but nearly free in some species, usually united in round or elongate

Angiopteris angustifolia, Hortus botanicus, Leiden, the Netherlands [7]

Angiopteris evecta, rhizome, Tahiti [7]

synangia (fused sporangia) that lack an annulus, but open by slits or pores, enclosing 1,000–7,000 spores. The spores are usually bilateral or ellipsoid and monolete. The gametophytes are superficial, heart-shaped, large and green. Distribution: Marattiaceae are distributed throughout tropical and subtropical regions of the world. Danaea, Eupodium and Marattia are found in tropical America from Mexico to Argentina, with Marattia also extending to Hawaii. Christensenia is found from the Himalayas through Southeast Asia and Malesia to the Solomon Islands. Angiopteris occurs from Madagascar, the Seychelles and southern India throughout tropical Asia to northeastern Australia and numerous Pacific islands as far east as Pitcairn. Ptisana (formerly Marattia of the Old World) occurs in tropical Africa, Madagascar, the Mascarenes, tropical Asia and Australasia, south to New Zealand and north to Japan. Phylogeny and evolution: Fossils of the distinctive stem anatomy and synangia place the origin of marattioid ferns in the Upper Carboniferous, making them one of the oldest extant lineages of land plants. Modern genera

are known with certainty from the Triassic and Jurassic and were widespread on continents of the Northern Hemisphere. The centre of diversity now lies in the northern Andes and southern China. The lineage is isolated and has no close extant relatives. The family is divided in two subfamilies: Danaeoideae, including only Danaea, and Marattioideae, in which the other genera are placed. Genera and species: Marattiaceae include six genera with c. 135 species: Angiopteris (c. 30), Christensenia (1), Danaea (c. 55), Eupodium (3), Marattia (c. 10) and Ptisana (c. 35). Uses: Starch from the rhizomes of some Angiopteris species is sometimes eaten in southern Asia, and Angiopteris rhizomes are used to flavour rice in Polynesia. In India, Angiopteris stems are used to make ruchshi, an intoxicating drink. The rhizome of Marattia douglasii was steamed and eaten by Hawaiians, and similarly Ptisana salicina was cultivated for consumption by Maoris in New Zealand. Etymology: Marattia was named for Italian botanist Giovanni Francesco Maratti (died 1777).

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MARATTIALES

FERNS

Danaea geniculata, Paraná, Brazil, detail of sori [7]

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Ptisana oreades, detail of sori, Australian National Botanic Gardens, Canberra [7]

Danaea polymorpha, Guadeloupe [7]

Eupodium kaulfusii, detail of sori, São Paulo, Brazil [7]

Eupodium kaulfusii, São Paulo, Brazil [7]

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OSMUNDALES

FERNS

LEPTOSPORANGIATE FERNS Families 8 to 33 are called leptosporangiate ferns. This is the crown-group of ferns. In all species the sporangia develop from a single epidermis cell. All other fern lineages (and seed plants and lycopods) are eusporangiate, meaning that the sporangia are developed from a group of cells. In leptosporangiate ferns, the sori are often covered in a scale-like structure called an indusium, a character frequently used in identification. The vast majority of extant ferns are leptosporangiate.

OSMUNDALES A widespread order with a fossil history going back to the Permian, they now comprise the single family Osmundaceae with sporangia that are intermediate between those of the Ophioglossales and the typical leptosporangiate ferns.

8. OSMUNDACEAE Royal-fern family

Todea barbara, National Botanic Gardens of Ireland, Glasnevin [8]

These terrestrial ferns have trunk-like rhizomes that are clothed in roots and leaf bases. Their petioles have stipules at the base. Leaves are monomorphic, fully dimorphic or with fertile portions dissimilar to the sterile parts on the same leaf, and are once to twice pinnate and hairy when young. The venation is free, usually forked. Their sporangia are free and not assembled in sori. They have a short stout stalk and a large capsule that can contain >100 to >1,000 spores. The capsule has an annulus that consists of a group of cells thickened on one side that makes the

Osmundastrum cinnamomeum, Hortus botanicus, Leiden, the Netherlands [8]

capsule open by an apical slit. Spores are green, subglobose, trilete, smooth and shortlived. The germination of the spores is bipolar. Gametophytes are large, superficial, green, heart- or ribbon-shaped and long-lived, and have a strong midrib, apical rhizoids and basal meristems. Distribution: Osmundaceae are cosmopolitan, except for hot, dry areas. Leptopteris is confined to Australasia, and Todea is found in three widely disjunct areas: South Africa, New Guinea and eastern Australia.

Leptopteris fraseri, New South Wales, Australia [8]

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OSMUNDALES

FERNS

Phylogeny and evolution: The stelar (root) structure of Osmundaceae is unique among ferns and allows assignment of fossils to this family, with certainty dating back to the Permian. No close relatives are known, which is not unusual for a lineage of such antiquity. It has been suggested that Osmundaceae are an intermediate stage towards leptosporangiate ferns. Molecular phylogenetic analyses have placed them as sister to all other leptosporangiate ferns, so it is possible that they represent a group of ferns that emerged around the time of the development of the leptosporangium. There are affinities to other early diverging fern lineages, including the presence of stipules, free venation, large spore output and sporangia that are sometimes formed by more than a single cell.

The cinnamon fern, often included in Osmunda, is sister to the rest of the extant taxa. To keep Todea and Leptopteris separate from Osmunda and to make the last monophyletic, the cinnamon fern has been segregated as Osmundastrum cinnamomeum. Genera and species: Osmundaceae consist of four genera with 23 species: Leptopteris (10), Osmundastrum (1), Osmunda (c. 10) and Todea (2). Uses: Young shoots (fiddleheads) and winter buds of cinnamon fern, Osmundastrum cinnamomeum, can be cooked and eaten. ‘Fern butter’ is the edible pith of the rhizome of the interrupted fern, Osmunda claytoniana. An edible starch is extracted from ‘zendai’, Osmunda japonica, in Japan.

The fibrous trunks of Osmunda regalis are sometimes used for orchid cultivation as a substitute for tree fern fibre, resulting in a threat to local populations and legal protection of the species in some countries. Etymology: The name Osmunda is of uncertain origin and was in use long before Linnaeus applied it. It may have originated from Old French osmonde, a kind of fern. It alternatively could have been derived from Old Saxon ås mund, god’s strength, referring maybe to the stately and rapid growth of the fern in spring. Alternatively it is possible that it was named for Saint Osmund, Bishop of Salisbury (died 1099), or another historical person with a similar name. The origin of the name remains shrouded in the mists of time.

HYMENOPHYLLALES This unusual group of ferns has thin leaves that are one cell thick. They diverged c. 243 million years ago. The order includes the single family Hymenophyllaceae with two genera that diverged during the Jurassic. They largely occur in the tropics where they are epiphytic.

Trichomanes elegans, São Paulo, Brazil [9]

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Trichomanes cuspidatum, Réunion [9]

Trichomanes endlicherianum, Tahiti [9]

HYMENOPHYLLALES

FERNS

Hymenophyllum sibthorpioides, Réunion [9]

9. HYMENOPHYLLACEAE Filmy-fern family

These are moss-like terrestrial or epiphytic ferns. They have slender, wiry and creeping or climbing, or erect and stout rhizomes, with or without roots. Leaves are simple to variously pinnately compound, or variously regularly or irregularly divided and can be small (< 2 mm) to intermediate in size (c. 50 cm) when mature. The blades are usually one or only a few cell layers thick and transparent and lack stomata. Venation is free or somewhat anastomosing, simple, forked or flabellately arranged. Sori terminate veinlets and are formed at the tips of ultimate segments or on lobe margins. The involucres

Hymenophyllum elegans, Paraná, Brazil [9]

are cup-shaped, usually two-lipped or bilobed, with a central receptacle that is often elongate and exserted, along which the sporangia are formed. The sporangia are short-stalked with a well-defined annulus. Spores are spheroidal, variously ornamented, green and short-lived, usually germinating inside the sporangium. Gametophytes are filamentous or ribbon-shaped and long-lived, reproducing vegetatively by proliferating buds in some species. Distribution: These moisture-dependent ferns occur predominantly in mossy forests in tropical montane regions and in temperate rain forests. They have a nearly worldwide distribution but are absent in areas with dry cold winters or hot dry summers. They can be found north to British Columbia and Norway and south to Tierra del Fuego and New Zealand. Vegetatively reproducing gametophytes have been reported from Germany, Luxemburg and eastern North America, in areas far colder than those where sporophytes of the same species occur. These gametophyte

populations have been presumed to be relics of warmer eras. Phylogeny and evolution: The fossil record of Hymenophyllaceae is sparse, but it has been suggested that the filmy leaf morphology is a derived character that evolved with the evolution of seed-plant-dominated tropical rainforests. They are an isolated lineage placed near Gleicheniales. Within Hymenophyllaceae, the two clades found correspond to the genera accepted here. Genera and species: Hymenophyllaceae consist of two genera with c. 650 species: Hymenophyllum (c. 350) and Trichomanes (c. 275). Trichomanes is sometimes divided into several smaller genera, but the genus is monophyletic when maintained in the broad sense, so the division into several genera serves no particular purpose. Etymology: Hymenophyllum is derived from the Greek υμένας (ymenas), a membrane or skin and φύλλων ( fyllon), a leaf, referring to the thin leaf texture of most species. Plants of the World

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GLEICHENIALES

FERNS

GLEICHENIALES This is a relatively isolated assembly of three similar families with a long fossil record. They are good indicators for present and past distributions of tropical vegetation.

Gleichenia microphylla, sori, New Caledonia [10]

Gleichenella pectinata, Guadeloupe [10]

Dicranopteris flexuosa, sori, Brazil [10]

Stromatopteris moniliformis, New Caledonia [10]

10. GLEICHENIACEAE

in regular clusters. Sporangia are short-stalked with a large capsule and numerous spores. The capsule has an oblique, nearly complete annulus. Spores are achlorophyllous. Gametophytes are elongate to subcordate, green in all genera except Stromatopteris, which has tuberous, achlorophyllous, mycoheterotrophic gametophytes.

Antarctica. With Dipteridaceae and Matoniaceae, the family forms an isolated lineage. Stromatopteris, endemic to New Caledonia, is sister to all other Gleicheniaceae and sometimes placed in its own family or subfamily.

Forking-fern family

These terrestrial ferns have creeping rhizomes that bear scales and/or hairs. Leaves are once-pinnate, the midribs often forking dichotomously and with axillary buds from which leaves can continue to grow indeterminately. Petioles have a single vascular bundle that is c-shaped in cross-section. Pinna segments are adnate and usually firm in texture, and venation is free. Sori are round, formed on the dorsal side of the leaf and exindusiate, with few sporangia, usually arranged

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Genera and species: Gleicheniaceae consist of six genera with c. 165 species: Dicranopteris (c. 20), Diplopterygium (c. 25), Gleichenella (1), Gleichenia (18), Sticherus (c. 100) and Stromatopteris (1).

Distribution: Gleicheniaceae are a pantropical family with their greatest diversity in the Neotropics and tropical Asia, extending occasionally into the subtropics. Many species are found in pioneer habitats or disturbed areas, roadsides, landslides etc. Gleicheniaceae prefer nutrient-poor soils and are often found in full sun, but then usually in montane areas where ample water is available.

Uses: Petioles of Dicranopteris linearis were woven into hats and cigar boxes on Java. In Malaysia they were used as pens and woven into mats, fishing traps and chair seats; they have even been used to make the walls of huts.

Phylogeny and evolution: This ancient family dates back at least to the early Mesozoic and possibly the Carboniferous. Fossils are known from all continents, including

Etymology: Gleichenia was named for German naturalist and plant physiologist Baron Wilhelm Friedrich von Gleichen (1717–1783).

GLEICHENIALES

FERNS

11. DIPTERIDACEAE Double-fern family

These are terrestrial or epilithic ferns. Their rhizomes are long-creeping and clothed with scale-like dark bristles or hairs. Petioles are placed centrally or basally on the blade and have one to several vascular bundles that are organised in a U-shape in cross-section. Leaves are monomorphic or strongly dimorphic. The blade is entire or divided deeply into two more or less equal parts, usually

glabrous (at least when mature), the margins deeply lobed, cleft or entire. Larger veins are palmately arranged at the base and forking several times, the smaller veins reticulate, and areoles with many included veinlets. The sori are small, round and exindusiate and cover the lower surface of the fertile leaves or are irregularly seriate. Sporangia are stalked, the stalks are four cells wide and the annulus is longitudinal, somewhat oblique. Sporangia are surrounded by hairs with a thickened tip. Spores are monolete or trilete, ellipsoid or tetrahedral, achlorophyllous, smooth or rugulose. Gametophytes are naked and heart-shaped, with a thick midrib and usually gametangia on both surfaces.

Phylogeny and evolution: This family consists of two isolated genera that, with Matoniaceae and Gleicheniaceae, form an isolated ancient lineage (Gleicheniales). In the past the family was associated with Polypodium, but this was only based on the shared lack of indusia. The family dates back to the Upper Triassic, with some fossils probably assignable to the extant genus Dipteris; the genus is thus of considerable antiquity and can be considered a “living fossil”.

Distribution: Dipteridaceae occur in tropical Asia and Australasia, from Assam to southern China and Okinawa, south to Queensland, New Caledonia and Fiji.

Etymology: Dipteris is derived from the Greek δυο (dyo), two, and πτέρης (pteris), fern, in reference to the biparted leaf.

Genera and species: Dipteridaceae consist of nine species in two genera: Cheiropleuria (1) and Dipteris (8).

Cheiropleuria integrifolia, Taiwan (RK) [11]

Dipteris conjugata, sori, New Caledonia [11]

Dipteris conjugata, New Caledonia [11]

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GLEICHENIALES

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Matonia pectinata, Malaysia (HW) [12]

12. MATONIACEAE Umbrella-fern family

These terrestrial or epilithic ferns have longcreeping, densely hairy rhizomes. Leaves are monomorphic, and petioles are dark and glossy, with a single simple vascular bundle. Blades have either pinnatifid pinnae that are pedately arranged or pinnae that are once forked and have axillary bulbils that cause indeterminate growth. Venation is free or

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somewhat reticulate. Sori are formed on the lower side of the leaves and are round and indusiate. The indusium is centrally attached and umbrella-shaped. Sporangia are few, large and placed in a circle around the indusium. The sporangium stalk is short, the capsule is subglobose and the annulus is oblique and incomplete (not surrounding the capsule entirely). Spores are trilete. Gametophytes are superficial, heart-shaped and naked, with antheridia on both sides and archegonia only on the lower side. Distribution: All extant members are restricted to the Malesian region and exhibit a relictual distribution. Matonia is restricted to the Malay Peninsula and Borneo, and Phanerosorus occurs only in the Moluccas. Usually they are found locally in tropical mountain areas on soils with low mineral content.

Phylogeny and evolution: Matoniaceae are of great antiquity, dating back to the Lower Mesozoic, and extant Matonia pectinata has been even considered to have been present since the Cretaceous. The family had a much wider distribution in the past based on their much more extensive fossil distribution. They have no close relatives, but the family is placed with Dipteridaceae and Gleicheniaceae in Gleicheniales based on DNA studies. Genera and species: Matoniaceae consist of two genera with four species: Matonia (2) and Phanerosorus (2). Etymology: Matonia is named for William George Maton M.D. (1774–1835), a fellow of the Royal College of Physicians, who had a keen interest in botany and was a friend of Robert Brown, who named this genus for him.

SCHIZAEALES

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SCHIZAEALES This order previously consisted of three families that are now united under the single family Schizaeaceae. They are remarkable in having sporangia that are borne on a marginal, pinnately arranged sporangiophore with each sporangium covered with a flap of leaf tissue.

These are terrestrial or epilithic ferns with creeping or suberect, articulately hairy rhizomes. Petioles have a single vascular bundle and are erect, sometimes twining. Blades are once or twice (to many-fold in

Lygodium) pinnate-pinnatifid, pinnatepalmatifid, or simple and pinnately lobed or dichotomously branched, sometimes absent or reduced to wings along a midrib. Veins are free, (dichotomously or flabellately) forking or rarely casually anastomosing; areoles, when present, are without included veinlets. Sporangia usually borne on sporangiophores or in two rows along a vein in a leaf tooth, usually pinnately or digitately arranged, usually each lateral veinlet bearing a sorus with a single sporangium and a flap of leaf tissue covering the sorus. Sporangia are asymmetrical, ovoid or pear-shaped, the annulus just below or at the apex. Spores are trilete or monolete, ellipsoidal, (sub-)globose or angular and are variously ornate. Gametophytes are

Actinostachys confusa, Seychelles [13]

Schizaea elegans, Peru [13]

13. SCHIZAEACEAE Fan-fern family

heart-shaped or filamentous, (partly) chlorophyllous and often with rhizoid cells, or (in Actinostachys) mycoheterotrophic, fleshy and tuber-like. Distribution: The diverse Schizaeaceae are mainly distributed in the tropics but extend in the Americas south to temperate South America and north to Newfoundland. They also occur in southern Africa, Madagascar and the Mascarenes, throughout tropical Asia, north to southern Japan and south to New Zealand. They usually grow on in mineralpoor soils often in open habitats, sometimes on decaying wood or on ultrabasic soils, but unlike other Schizaeaceae, Lygodium is usually found on fertile soils. Lygodium japonicum, Copenhagen Botanical Garden, Denmark [13]

Schizaea dichotoma (WA) [13]

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SCHIZAEALES

Lygodium volubile, sori, Brazil [13]

Phylogeny and evolution: Schizaeaceae are the single extant family in the order Schizaeales, which form the sister lineage to core leptoporangiate ferns (including Polypodiales, Cyatheales and Salviniales), a lineage of considerable age originating in the Jurassic. The three lineages, represented here at the subfamily level, diverged early in their evolutionary history and have therefore been separated as independent families in some classifications, even though they share major characters and were in historical classifications usually placed in a single family (as done here). Lygodioideae are sister to the rest and stand apart morphologically from the other two subfamilies in having oblique sporangia and climbing habits. The two genera in Schizaeoideae differ

FERNS

Anemia sp., near Ubatuba, Brazil [13]

Anemia vestita, Kenya [13]

mainly in gametophyte and sporangium structure, Actinostachys having mycoheterotrophic gametophytes and pseudodigitate sporangiophores. The oldest fossil assigned to Schizaeoideae dates from the Cretaceous. In Anemioideae two lineages were recognised on the basis of morphological differences, but the African genus Mohria was found to be embedded in Anemia s.s., Mohria being clearly derived from Anemia. The resemblance of Mohria to cheilanthoid ferns rests mostly upon a superficial similarity, convergence probably due to similarities in habitat preference. Genera and species: Schizaeaceae, with three subfamilies, comprise four genera and c. 190 species: Lygodioideae – Lygodium (c. 35); Anemioideae – Anemia (c. 115);

Schizaeoideae – Actinostachys (16) and Schizaea (21). Uses: Anemia caffrorum and related species give off an aroma of balsam when bruised. The essential oils are antibacterial, can be used to treat burns and are used in South Africa to prevent children’s nightmares. The twining rachises of Lygodium salicifolium are used in Thailand as a material for weaving. Occasionally used as an ornamental in the tropics, some species especially Lygodium japonicum and L. microphyllum have locally become serious weeds outside their native range. Etymology: Schizaea is derived from Greek σκίζει (skizei), to split.

SALVINIALES Families 14 and 15 are placed in the order Salviniales, also sometimes referred to as the heterosporous ferns. They are distinguished from other ferns in having two sizes of spores, megaspores and microspores, that are formed in a sporocarp, a hard structure in which the sporangia are formed; it is hypothesised to be an adaptation to their aquatic habitat.

14. MARSILEACEAE Pillwort family

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These are small terrestrial ferns of swampy, periodically wet or permanently flooded places. Their rhizomes are slender, creeping and much branched. They have air canals and bear hairs, but become glabrous later. Leaves are formed in two rows along the rhizome and are hairy when young. Petioles have a single V-shaped vascular bundle. Blades are lacking (Pilularia) or the lamina has two (Regnellidium) or four (Marsilea) segments, these pinnately

arranged, but the rachis nearly lacking, making the lamina appear palmate and clover-like. Veins are flabellately arranged, forking, and usually anastomosing on both ends, without included veinlets. Sori are formed inside firm, globose or ellipsoidal stalked sporocarps (a modified globose indusium), inserted on the petiole or on the rhizome near the petiole base. Sporocarps are long-lived and dehisce into two valves upon water uptake by the gelatinous interior

SALVINIALES

FERNS

Marsilea drummondii, South Australia [14]

Marsilea mutica, private pond, Kingston upon Thames, Surrey, UK[14]

that contains two or more sori carried out by the protruding gelatinous mass, containing the mega- and microsporangia that lack an annulus. Spores are trilete and of two different sizes: a single large one is formed in each megasporangium, and many small ones are formed in each microsporangium; the microspores are free. Spores germinate rapidly, the microspores producing spermatozoids within a day of germination, fertilisation occurring soon after germination of spores. Gametophytes are greatly reduced, consisting of a few cells only; they remain attached to the spores and are often developed and fertilised within the spore.

relationships of heterosporous water ferns (Marsileaceae and Salviniaceae) have long been disputed. They were previously placed in Hydropteridales, with some fossil taxa, usually among ferns, but sometimes among ‘fern allies’. Molecular phylogenetic studies have placed the heterosporous ferns as sister to the rest of the families in core leptosporangiates, heterospory (among vascular plants otherwise only known in Selaginellaceae and Isoëtaceae) being a derived character and probably an adaptation to their aquatic habitat. Macrofossils of Marsileaceae are known from the Upper Jurassic and later.

Distribution: A family of nearly worldwide distribution, but absent from cold or extremely dry regions and most oceanic islands. Some Australian species of Marsilea are drought resistant and can be found in desert environments, but usually in periodically wet areas. Sporocarps are usually produced in areas where the water level fluctuates and the plant dries out. Plants thrive in permanently flooded areas, but sporocarps are not always produced when the plant is submerged.

Genera and species: Marsileaceae consist of three genera with c. 65 species: Marsilea (c. 60), Pilularia (5) and Regnellidium (1).

Phylogeny and evolution: Placement and

Uses: Sporocarps of nardoo (Marsilea drummondii) were ground into flour and baked into bread by aboriginal Australians. The spores are, however, indigestible, provide no nutrition and are astringent. A diet of just nardoo bread results in death from starvation with a full stomach. Etymology: Marsilea was named for Italian mycologist Count Luigi Marsigli (1656–1730).

Pilularia globulifera illustration from O. W. Thomé (1885) Flora von Deutschland, Österreich und der Schweiz, Gera, Germany. [14]

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SALVINIALES

15. SALVINIACEAE Water-fern family

These are free-floating aquatic plants. Stems are horizontal, green, branched and floating. The two genera differ substantially (and were previously placed in separate families) and therefore are described here separately. Azolla has simple, unbranched roots on the lower side of the stems. Leaves are sessile, alternate, and formed in two rows on the upper side of the stem, each leaf bilobed, with one lobe upright, chlorophyllous, with a cavity harbouring colonies of the blue-green alga Anabaena, the other lobe floating, mostly without chlorophyll. Sori are formed inside sporocarps (modified indusia), the sporocarps formed on the first leaf of a side branch, replacing the lower lobe and the upper lobe covering the sporocarp. Sporocarps contain either micro- or megasporangia. The megasporocarps (containing a single sporangium) are smaller than the microsporocarps (containing numerous sporangia). Sporangia lack an annulus and spores are filamentous. Microspores

FERNS

are trilete and embedded in hardened mucilage. Megaspores have hair-like filaments and floats. Gametophytes of microspores reduced with a single antheridium. Gametophytes of the megaspores develop within the spore. Salvinia lacks roots. Leaves are formed in whorls of three along the length of the stems; the two upper leaves are floating and green, the lower one is submerged, much branched and root-like. The floating leaves are sessile or slightly stalked, ovate to cordate, with specialised water-repelling hairs on the upper surface. The veins are pinnate and lateral veins anastomose, the areoles without included veinlets. The submerged leaves are petiolate, finely divided and hairy, and the branches bear sporocarps. Sori develop inside sporocarps (globose indusia), one or a few of these sporocarps producing megasporangia and the other sporocarps producing microsporangia. Sporangia lack an annulus. Spores are spherical, plain to rugose. Microspores are enclosed in a hardened mass. Megaspores are trilete. Gametophytes of microspores are reduced, formed of only a few cells, and bear reduced antheridia. Gametophytes of megaspores are free-floating, heart-shaped and connected to the megasporangium. Distribution: The genera occur in southern North America, South America, Europe and western Asia and throughout the Palaeotropics, except Australasia. The plants are free-floating on fresh water surfaces such as

Salvinia natans, Helsinki Botanical Garden, Finland [15]

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Salvinia molesta, submerged root-like leaf, Tahiti [15]

ponds, rice paddies, river margins, ditches, drainage and irrigation canals, in swamps, bogs etc. Phylogeny and evolution: The two genera (previously often placed in separate families) are closely related and the pair are sister to Marsileaceae. Together these families form a lineage of heterosporous ferns, which is sister to the rest of the core leptosporangiates. Their fossil history dates back to the Cretaceous. The genera are morphologically divergent and for that reason each has been placed in its own subfamily. Genera and species: Salviniaceae consist of two genera with c. 20 species in two subfamilies: Azolloideae – Azolla (7); Salvinioideae – Salvinia (12). Uses: Because of its nitrogen-fixing cyanobacteria, Azolla pinnata is released in rice paddies in East Asia to fertilise the soil. A paddy overgrown with Azolla is drained, and the plants are ploughed into the soil before young rice is planted. Azolla filiculoides and Salvinia molesta are invasive species outside their native range and, when cultivated, release of these plants into nature needs to be prevented. Both genera are employed as biofilters to remove toxic compounds from waste water. Etymology: Salvinia was named for Italian botanist A.W. Salvini (1633–1729).

Azolla filiculoides, France [15]

CYATHEALES

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CYATHEALES The order Cyatheales was previously divided into eight families that vary greatly in general appearance, but these all share a helicogyroid annulus that bypasses the stalk of the sporangium. There are members that look like filmy ferns (some Cyathea), some that are tree-like (many Cyatheoideae and Dicksonioideae) and some (Plagiogyria) that more closely resemble hard ferns (Blechnum, Aspleniaceae) with creeping rhizomes and pinnate leaves, but all are now united in a single family: Cyatheaceae. Because some of the former family names are still commonly in use and are equivalent to current subfamilies, we opted to treat all subfamilies separately here.

16. CYATHEACEAE Tree-fern family

Cyatheaceae are a variable group of terrestrial or epilithic ferns, including some of the smallest and some of the largest ferns known. Rhizomes are creeping or erect, often trunklike, and covered in scales or hairs. Leaves are minute to large, 5–500 cm. Petioles have a single vascular bundle that is usually U- or V-shaped in cross section. Blades are rarely simple, usually once or up to five times pinnate. Veins are usually free or somewhat anastomosing near the margin, rarely fully anastomosing, the free veins often not reaching the margin. Sori usually develop on veins, dorsally or marginally, round, the receptacle raised or cup-shaped, with the indusia usually surrounding the receptacle, or the indusia fixed on one side of the sorus and scale-like; indusia are sometimes completely absent. Sporangia are stalked with a nearly vertical, oblique annulus that bypasses the sporangium stalk. Spores are trilete and globose, sometimes angular and variously ornamented. Gametophytes are green and heart-shaped and often scaly. Distribution: This is a pantropical family, extending into the subtropics and wet temperate regions of the Southern Hemisphere. Some temperate, mainly Australian

species are naturalised in suitable habitats in the Northern Hemisphere, including coastal British Columbia, Hawaii, the Macaronesian Islands and western Ireland and Britain. Phylogeny and evolution: This family is the single extant representative of the tree fern lineage, order Cyatheales. These include treelike species with tall trunks and large leaves, but also include minute species with trunks and leaves only a few centimetres long (former genus Hymenophyllopsis, now included in Cyathea). The family also includes some species of intermediate size with creeping rhizomes similar to members of Polypodiales, and species of this group have often been confused with members of Dennstaedtiaceae or Davallia (Polypodiaceae). The group is characterised by oblique annuli on the sporangium capsules. Molecular divergence of tree ferns is slow, which could be due to their long generation times, as has been hypothesised for palms. The current diversity of tree ferns is thus possibly relatively recent and the subfamilies discussed below probably date from the Jurassic with some lineages being of a relictual nature. Others, especially the species-rich Cyatheoideae, have diversified in more recent times, with many species in montane rainforests of the tropics. Genera and species: Cyatheaceae include eight subfamilies with 12 genera totalling about 700 species: Alsophila (c. 260), Calochlaena (6), Cibotium (11), Culcita (2), Cyathea (c. 275), Dicksonia (22), Lophosoria (1), Loxsoma (2), Metaxya (2, probably more), Plagiogyria (c. 15), Sphaeropteris (c. 100) and Thyrsopteris (1). The subfamilies are described separately below because they are sometimes treated at the family level.

Uses: The growing tips of tree ferns are rich in starch and sometimes roasted and eaten, although this usage is not sustainable because it kills these slow-growing plants. This usage has, however, been reported from native peoples in Madagascar, Australia, New Zealand and New Caledonia, and Cibotium billardieri was eaten in Hawaii. The young leaves (fiddle-heads) are also eaten in some cultures and supposedly taste like bitter celery or palm heart. Tree fern trunks are widely used in construction and carving, and the peaty root-masses make good flower pots or growing medium for orchids; due to this last utilisation, international trade in Cyathea and Dicksonia is currently regulated by CITES. The fluffy scales of Cibotium, Culcita and other tree ferns were harvested on a large scale as stuffing for pillows and were frequently used in the seat cushions of early cars. Many species are popular ornamental plants in the tropics and subtropics. Etymology: Cyathea is derived from the Greek κυάθιος (kyathios), a cup or beaker, in reference to the shape of the indusium in some species.

16a. CYATHEACEAE SUBFAMILY THYRSOPTERIDOIDEAE Robinson-Crusoe ferns These terrestrial ferns have erect or curved upright rhizomes that are covered with stiff hairs. Leaves are large and long-petiolate, the petioles hairy at the base, and have a single Ω-shaped vascular bundle in cross-section. Blades are three- to five-pinnate, firm and glabrous when mature. Veins are free and do not reach the leaf margins. Fertile portions are

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CYATHEALES

FERNS

Thyrsopteris elegans, Glasgow Botanic Gardens, Scotland, UK [16a]

found on the basal part of the blade, where the pinnae are much dissected and almost without blade tissue. The sori are formed terminally on stalk-like veins, and the indusia are fused to form a cup in which the sporangia are placed on a column-shaped receptacle. Sporangia have a stalk with a complete annulus. Spores are globose-tetrahedral, prominently angular, verrucate. Gametophytes are green and superficial. Distribution: Thyrsopteridoideae are endemic to the Juan Fernández Islands, an archipelago off the coast of Chile in the southeastern Pacific. Phylogeny and evolution: Fossils of Thyrsopteridoideae are widespread, and the current restricted distribution is therefore certainly relictual. The lineage is of greater age than the age of the volcanic Juan Fernández Islands, and the genus was once widespread across South America, but died out there and only remained on these isolated islands. Genera: Thyrsopteridoideae include only a single, relictual, extant species: Thyrsopteris elegans. Etymology: Thyrsopteris is derived from the Greek θύρσος (thyrsos), a stalk or stem of a

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Loxsoma cunninghamii, collected by Colenso in New Zealand (Herbarium Kew, ex coll. Hooker) [16b]

plant, and πτέρης (pteris), a fern, in reference to the stalked sori.

northern Andes. They occur in open places in moist lowland forests.

16b. CYATHEACEAE SUBFAMILY LOXSOMATOIDEAE Cross ferns

Phylogeny and evolution: The disjunct distribution is an indication that the distribution of this subfamily may be relictual, although long-distance dispersal cannot be excluded. The widespread fossil genus Stachypteris from the Jurassic has been placed in this subfamily with certainty. Previously the subfamily was associated with Hymenophyllaceae and Dipteridaceae, based on superficial similarity (the urn-shaped sori and the bristle-like rhizome hairs, respectively). The gametophytes with scale-like hairs are similar to some Cyatheoideae, and an association, albeit distant, with that subfamily has been demonstrated in molecular studies.

These terrestrial ferns have long-creeping, branched rhizomes with stiff bristles. Leaves are placed distantly along the rhizome and are two- or three-pinnate-pinnatifid. Petioles are bristly-hairy at base, naked elsewhere and long, with a single, sickle-shaped vascular bundle in cross-section. Blades are firm with deltate-lanceolate pinnules. Veins are free, forked or somewhat pinnate. Sori terminate a vein and have an urn-shaped indusium; they are marginal and attached to the lower side of the blade, with a columnar central receptacle. Sporangia are formed among multicellular hairs and are stalked, pear-shaped, with a subvertical, somewhat oblique annulus. Spores are trilete, tetrahedral-globose, tuberculose or rugose, pitted and ridged. Gametophytes are a superficial, green, elongate, heart-shaped prothallus with multicellular scale-like hairs, especially above. Distribution: Loxsomatoideae are disjunctly distributed in northern New Zealand and in the Neotropics from Costa Rica to the

Genera and species: Loxsomatoideae consist of two genera with two species: Loxsoma cunninghamii in New Zealand and Loxsomopsis pearcei in the Neotropics. The species are closely related, morphologically similar and could be treated in a single genus. Etymology: Loxsoma is derived from the Greek λοξός (loxos), crosswise or oblique, and σώματος (somatos), body. The name was originally published erroneously as ‘Loxoma’, and later ‘corrected’ by the authors as Loxsoma.

CYATHEALES

FERNS

16c. CYATHEACEAE SUBFAMILY CULCITOIDEAE Cushion ferns

Caribbean, and in the Azores, Madeira, Tenerife and northwestern Spain. They are usually found in wet open forests.

These large terrestrial ferns have thick creeping or ascending rhizomes. The rhizomes are covered in persistent petiole bases and long hairs. Leaves are closely placed at the apices of the thick trunks. Petioles are covered with yellowish or brownish long hairs and have a single U-shaped vascular bundle in cross-section. Blades are four- to five-pinnatepinnatifid and are slightly hairy to glabrous. Veins are free, usually forking and reaching the leaf margins. Fertile portions of the leaf are similar to sterile portions or the lamina of fertile portions are somewhat reduced in size. Sori are formed marginally, terminating a vein, and are surrounded by two indusia on either side and have a central transversely elongate receptacle on which the sporangia are formed. The outer indusium is similar to the leaf blade and is fused with the inner indusium. Spores are globose-tetrahedral, depressed between the angles and variously ornate. Gametophytes are superficial, green and heart-shaped.

Phylogeny and evolution: Culcitoideae are sister to Plagiogyrioideae and not closely related to Calochlaena, a genus previously included in Culcita, but now placed in Dicksonioideae. The disjunct distribution of Culcitoideae may be relictual, but is more probably due to long-distance dispersal along the prevailing winds following the Gulf Stream.

Distribution: Culcitoideae occur disjunctly in tropical America from southern Mexico to Bolivia, Venezuela and throughout the

These are terrestrial ferns with erect or rarely creeping, naked rhizomes. Leaves are spirally arranged and closely placed on the rhizome

Genera and species: Culcitoideae consist of the single genus Culcita with only two species: C. coniifolia in the Neotropics and C. macrocarpa in Europe. Etymology: Culcita is Latin for cushion, in reference to the densely woolly rhizomes, which were harvested to fill pillows and car seat-cushions.

16d. CYATHEACEAE SUBFAMILY PLAGIOGYRIOIDEAE Pheasant-tail ferns

Culcita macrocarpa, private garden, England, UK [16c]

forming a rosette. Petioles are distinct, swollen at base, with knob-like aerophores along the side and with a single V- or U-shaped vascular bundle, quadrangular or triangular, sometimes round in cross-section. Leaves are hairy when young, the hairs excreting mucilage (hence the aerophores), becoming glabrous when mature. The blades are simple and pinnatifid or once pinnate and strongly dimorphic (sterile leaves different from fertile leaves). Sterile pinnae are sessile or adnate to the rachis and are usually serrate. Veins are free, simple or forking and the tips are enlarged near the margins, ending in margin teeth. Fertile leaves are much contracted, nearly lacking blade tissue and are held upright, the pinnae are narrowly linear, covered below in the sporangia (acrostichoid). Sporangia are borne on veins on the lower side of the lamina; indusia are absent, but the sorus is often (partly) covered by the recurved leaf margins. Sporangia are longstalked and the capsule is asymmetrical with a complete, oblique, thickened annulus. Spores are trilete, tetrahedral, depressed between angles, papillate and tuberculate. The gametophytes are green and heart-shaped. Distribution: Plagiogyrioideae usually occur in mountain areas in the tropics, where they can occur at high elevations. They are found in the Neotropics from Mexico to Bolivia,

Plagiogyria falcata, Taiwan (RK) [16d]

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CYATHEALES southeastern Brazil and the Greater Antilles and in Asia from the eastern Himalayas to New Guinea and Japan (Hokkaido). Plagiogyrioideae are most species-rich in East Asia. Phylogeny and evolution: Previously Plagiogyria was included in Blechnum (Aspleniaceae) due to a striking superficial resemblance, but it was already then known that the oblique annulus was a character more closely associated with the tree ferns than with Blechnum. Molecular phylogenetic analyses confirm this and place Plagiogyria as sister to Culcita in the family Cyatheaceae. Genera and species: Plagiogyrioideae consist of the single genus Plagiogyria, with c. 15 species.

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persistent roots and petiole bases, and are densely clothed in long yellowish-brown multicellular hairs. Leaves are clustered at the rhizome apex. Petioles have pneumatophores forming a line on each side and three vascular bundles. Blades are two or three-pinnatepinnatifid, firm and frequently whitish below. Veins are free, simple, forked or pinnate, reaching the leaf margin. Fertile and sterile segments are similar. Sori are formed at a vein ending and are marginal with two indusia, the outer indusium differentiated from the lamina, the inner tongue-shaped. The two indusia are fused at the base. Sporangia are usually formed among hairs. Spores are tetrahedralglobose, often with a prominent equatorial flange and a coarse ridge. The gametophytes are green and heart-shaped.

Legend: Cibotium barometz is the “vegetable lamb of Tartary”, which was harvested for symbolic and ritual purposes. The legendary vegetable lamb was originally described as “being both animal and plant and was a fruit of a tree that sprang from a seed like a melon or gourd that, when fully ripe, burst open and contained a perfectly formed little lamb”. This original description may have actually referred to ‘vegetable wool’ or cotton (Gossypium, Malvaceae), but in later descriptions fantasy took over and the vegetable lamb was described as “a lamb from flesh, bone and blood that was attached by its navel on a stem growing from the ground, sufficiently flexible to allow the lamb to graze on the vegetation around it”. When turned upside down, a rhizome of Cibotium with four cut petioles somewhat resembles a sheep and these creations, popular in curiosity cabinets of the Enlightenment, probably originated from toy-like figures formerly made in China from the rhizomes in that fashion.

Etymology: Plagiogyria is derived from the Greek πλάγιος (plagios), sideways or oblique and γύρος (gyros), round, referring to the oblique annulus.

Distribution: The subfamily occurs in southern Mexico and Mesoamerica (two species), in tropical East Asia from northeastern India to Japan and Borneo (three species) and on the Hawaiian Islands (six species).

16e. CYATHEACEAE SUBFAMILY CIBOTIOIDEAE Vegetable lambs

Phylogeny and evolution: There is some morphological similarity with Dicksonioideae, to which this subfamily is related.

These huge terrestrial tree-like ferns have massive, creeping to erect rhizomes, with

Genera and species : Cibotioidae consist of a single genus Cibotium with 11 species.

Etymology: Cibotium is derived from the Greek κιβωτίων (kibotion), a chest, container or box. Barometz is the Tartar name for the Scythian lamb, referring to the woolly rhizome that resembles a lamb with the legs being formed by the petiole bases.

Cibotium schiedei, Royal Botanic Gardens, Kew, UK [16e]

Cibotium barometz, rhizome, Singapore Botanic Garden [16e]

The barometz or vegetable lamb, from H. Lee (1887), The vegetable lamb of Tartary, London [16e]

Christenhusz, Fay & Chase

CYATHEALES

FERNS

Sphaeropteris intermedia, Jardin des Plantes, Paris, France [16f]

Cyathea arborea, Guadeloupe [16f]

Cyathea grandifolia, Guadeloupe [16f]

Alsophila imrayana, Guadeloupe [16f]

16f. CYATHEACEAE SUBFAMILY CYATHEOIDEAE Scaly tree-ferns

hairy, the pinnae or pinnules are variously shaped, depending on species and placement on the leaf. Veins are pinnate, free and simple or forked or anastomosing, forming arches along the midrib, usually the veins not reaching the margin. Sori are formed dorsally on the veins (rarely terminally), round, the receptacle is strongly raised or not. Indusia are attached around the receptacle bases and sometimes rupture upon opening, attached at one side only and scale-like or completely absent. Sometimes (as in Sphaeropteris) the indusium is replaced by a group of scales around the receptacle. Sporangia are stalked and usually surrounded by multicellular hairs, with a nearly vertical (slightly or strongly oblique) complete annulus that bypasses the sporangium stalk. Spores are trilete and globose. Gametophytes are green and heart-shaped.

some of the smallest. They are more common and more diverse in montane areas in the tropics, but a suite of species prefers lowland rainforests.

These are often large, occasionally tiny (Cyathea subgenus Hymenophyllopsis), terrestrial or epilithic ferns. The rhizomes are usually long and erect, slender or robust, usually tree-like and erect, rarely scandent, sometimes short and ascending or long creeping, often covered in a mantle of adventitious roots and bearing prominent leaf scars. The rhizomes are covered in non-clathrate scales, which distinguish Cyatheoideae from Dicksonioideae (that have only hairs on the tips of the trunks). Leaves are spirally arranged at the tips of the rhizomes. Petioles bear scales that are often inserted on wart- or spine-like outgrowths and are often also hairy. Petioles have discontinuous lines of pneumathodes, and vascular bundles are grouped in two arches, but often with additional series within this, or the vascular bundles are reduced to two simple ones only. Blades are pinnate or bipinnate-pinnatifid, rarely simple or tripinnate-pinnatifid, sometimes with the lowest pinnae strongly reduced (aphlebia), monomorphic. The lamina is scaly and usually

Distribution: This is a pantropical subfamily, extending into warm temperate zones in Australia, New Zealand, southern South America, southern China and southern Japan. Cyatheoideae are widely distributed and reaches many tropical islands. The subfamily includes the tallest extant ferns, but also

Phylogeny and evolution: Cyatheoideae are related to the other tree ferns, especially closely to Dicksonioideae. The oldest fossils assigned to the subfamily date from the late Jurassic. Being the most diverse and dominant tree fern lineage, Cyatheoideae are often associated with the Carboniferous forests, but the dominant tree ferns in that era were Marattiales. Molecular studies have shown that the genera Cnemidaria, Trichipteris and Hymenophyllopsis fall within Cyathea, all sharing morphological characters. Genera and species: This subfamily includes one to five genera (depending on the taxonomist; we accept three here), with c. 635 species: Alsophila (c. 260), Cyathea (c. 275) and Sphaeropteris (c. 100). Etymology: Cyathea is derived from the Greek κυάθιος (kyathios), a cup or beaker, in reference to the cup-shaped indusia of some species.

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CYATHEALES

Dicksonia antarctica, private garden, Kingston upon Thames, Surrey, UK [16g]

Calochlaena dubia, Helsinki Botanical Garden, Finland [16g]

Lophosoria quadripinnata, University of California Botanical Garden, Berkeley, USA [16g]

16g. CYATHEACEAE SUBFAMILY DICKSONIOIDEAE Hairy tree-ferns

are similar to the lamina. They surround the sorus forming a cup or the sori are exindusiate (Lophosoria). The central receptacle is hairy and raised or not. Sporangia are stalked with a complete, oblique or subvertical annulus. Spores are globose, sometimes angular and variously ornamented. Gametophytes are green, heart-shaped and somewhat irregular.

Culcita, but it differs from Culcitoideae in numerous characters. The two subfamilies are not closest relatives. The relationship with Metaxyoideae is also distant.

Distribution: This subfamily occurs in mountain areas of the Neotropics from Mexico to Venezuela and southeastern Brazil and temperate Chile, the Greater Antilles and on the Juan Fernández Islands, on St Helena in the mid Atlantic, and in tropical Asia from the Philippines, through Indonesia into eastern Australia, Tasmania, New Zealand and Samoa, with the greatest diversity in the mountains of New Guinea.

Etymology: Dicksonia was named for Scottish botanist James Dickson (1738–1822), who studied cryptogamic plants under the guidance of Joseph Banks.

These terrestrial ferns have roots that often form a thick mantle around the trunk-like rhizomes that can be erect and up to several metres tall in most Dicksonia species, but are creeping-ascending and sometimes branching in the other genera of the subfamily. The trunk apices are covered with multicellular hairs, distinguishing them from Cyatheoideae (which bear scales at the trunk apex). Petioles have three vascular bundles or have the bundles converging into a single U-shaped bundle in cross-section. The petiole base is clothed in hairs, and pneumathodes form a continuous line along the sides of the petioles or are small, interrupted and inconspicuous, sometimes absent. The petioles have proliferating buds in Lophosoria. Blades are bi- to quadripinnate-pinnatifid, gradually narrowed at the base and apex and are often persistently hairy. Pinnules are usually serrate or lobed. Veins are free, simple, paired or forked at base or pinnate. Fertile pinnae are not or slightly reduced. Sori are formed terminally on a single vein. The indusia are basally fused and

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FERNS

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Phylogeny and evolution: Lophosoria was often placed in its own family because it appears morphologically intermediate between Cyathea and Dicksonia. Molecular evidence places it with Dicksonia and Calochlaena in Dicksonioideae. It is distinctive in its flanged spores. Calochlaena was previously considered part of the genus

Genera and species: Dicksonioideae consist of three genera with c. 29 species: Calochlaena (6), Dicksonia (22) and Lophosoria (1).

16h. CYATHEACEAE SUBFAMILY METAXYOIDEAE Silk ferns These terrestrial ferns have creeping or ascending, short rhizomes that are clothed with silky multicellular hairs. Their petioles have a single Ω-shaped vascular bundle in cross-section and have lateral pneumathodes. Petioles are hairy or become glabrous and sometimes have proliferous buds at their base. Blades are once pinnate, the terminal pinnae similar to the lateral ones. Pinnae are stalked and lanceolate. Veins are free, paired or once

POLYPODIALES

FERNS

forked, the ends merging with the thickened margin. Sori are irregularly arranged on the lower side of the pinnae, with one or several on a vein, rounded, without indusia, the receptacle with thin hairs. The sporangia are many per sorus, shortly stalked, with a vertical, complete annulus bypassing the stalk. Spores are trilete and globose. Gametophytes are green, heart-shaped, with reproductive organs on the upper side and a primitive type of antheridium. Juvenile plants have much dissected leaves, looking unlike adult plants.

Distribution: This subfamily is restricted to tropical America from Mexico to Bolivia, Amazonia, the Guianas and Trinidad. Formerly it also occurred on Guadeloupe, where it is now extinct. Phylogeny and evolution: Morphologically Metaxyoideae have the greatest similarity to Lophosoria. The subfamily has been shown to be close to Dicksonioideae in molecular phylogenetic analyses. It is not known from the fossil record.

Metaxya rostrata, Loreto, Peru [16h]

Genera and species: Metaxyoideae consist of the single genus Metaxya, with seven species. Etymology: It is derived from the Greek μεταξύ (metaxy), intermediate, a name in the past also used for silk traders, intermediate between East and West. This fern has silky rhizome hairs, which may be the reason for its name, although the etymology of the name was not documented. Metaxya parkeri, specimen collected by l’Herminier in 1873 from Guadeloupe, where this species is now extinct (Kew Herbarium) [16h]

POLYPODIALES Families 17 to 24 represent the order Polypodiales or the ‘polypod ferns’. This includes some early branching lineages such as Lindsaeaceae, the pteridoid lineage (Dennstaedtiaceae and Pteridaceae) and the two eupolypod lineages, Aspleniaceae and Polypodiaceae. Polypodiales include the vast majority of extant ferns.

17. LONCHITIDACEAE Velvet-fern family

These terrestrial ferns have stout, shortcreeping, fleshy often green rhizomes. All parts are covered in pale hairs. Petioles arise on the upper side of the rhizome only, leaving round scars when withered, and have two vascular bundles that are well developed. Blades are succulent, once to three times pinnate-pinnatifid, the pinnae subopposite, subsessile and adnate to the rachis or shortly stalked, and the margins entire and lobed. Veins are free or irregularly joining,

the areoles without included veinlets. Sori are marginal, joining several veins, and are confined to the sinuses between lobes or occur along the entire blade margin. Indusia are elongate, formed by the reflexed, modified leaf margin. Receptacles are hairy, and sporangia formed among these hairs have three-celled stalks; capsules have a defined annulus. Spores are trilete, globose and granulate. Gametophytes are green and heart-shaped.

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POLYPODIALES

FERNS

Saccoloma dominguense, Guadeloupe [18]

46

Lonchitis hirsuta, Guadeloupe [17]

Saccoloma inaequale, Brazil [18]

Saccoloma dominguense, Guadeloupe [18]

Distribution: The family occurs in tropical America and tropical Africa and Madagascar, usually locally abundant in moist tropical forests, often along streams.

Genera and species: Lonchitidaceae consist of the single genus Lonchitis with two species: L. hirsuta in the Neotropics and L. occidentalis in tropical Africa.

Phylogeny and evolution: Traditionally Lonchitis was placed in Dennstaedtiaceae, close to Blotiella, which it resembles, but these genera differ markedly in rhizome structure, spore morphology and chromosome number. More recently, it was placed in Lindsaeaceae, where some molecular analyses place it, always with weak support. The placement of Lonchitidaceae is among the early polypods, a still unresolved part of the fern phylogenetic tree. It appears that early polypods evolved rapidly, and therefore the independent lineages are difficult to place. Because including Lonchitis in Lindsaeaceae would stretch the morphological circumscription of that family and relationships among early polypods remains uncertain, it has now been accepted as a separate family.

Etymology: Lonchitis is derived from the Greek λόγχ (longch), a lance or spear.

arranged spirally on all sides and have a single vascular bundle. Blades are decompound or (rarely) once pinnate. Veins are free, simple or forked and do not reach the margins. Sori terminate a single vein. The indusium is cupor pouch-shaped and formed close to the margins. Receptacles are glabrous. Sporangia have three-celled stalks and capsules with a defined annulus. Spores are trilete, tetrahedral-globose, prominently ridged and granulate. Gametophytes are green and heart-shaped.

Christenhusz, Fay & Chase

18. SACCOLOMATACEAE Pouch-fern family

Distribution: Saccolomataceae are widespread in the Neotropics, Madagascar, tropical Asia, Australasia and the western Pacific. They are usually found in shady banks in tropical rainforests.

These are terrestrial ferns with trunk-like or short-creeping, scaly rhizomes. Hairs are absent from all parts of the plant. Petioles are

Phylogeny and evolution: This distinctive family has often been placed in Dennstaedtiaceae, but even within that has long been recognised as a subfamily. They form one

POLYPODIALES

FERNS

of the early branching polypod lineages, and its placement is not certain; it is clear though that they are not close to Dennstaedtiaceae. Because of their distinctive morphology and molecular isolation, they are treated in their own family. Genera and species: Saccolomataceae consist of about 12 species that are usually included in the single genus Saccoloma, although species with decompound leaves have been separated into Orthiopteris.

and sparsely hairy. Pinnules are sessile, oblong and serrate. Veins are simple, paired or forked. Fertile pinnules are slightly contracted, the sori are formed marginally, terminating a vein, the vein extending into two small indusium lobes, the larger of the two lobes dome-shaped, covering the sorus, with numerous hairs among the sporangia. The sporangia are stalked with a complete annulus. Spores are globose, ridged and rugulose. Gametophytes are green and heart-shaped.

Genera and species: Cystodiaceae consist of the single genus Cystodium with only one species: C. sorbifolium. Etymology: Cystodium is derived from the Greek κυστός (kystos), a bladder or pouch, in reference to the pouch-shaped indusium.

Distribution: This is a pantropical family with representatives in temperate Africa, Brazil, southern Australia, New Zealand, the

Distribution: Cystodiaceae occur in tropical Asia from Borneo eastwards to the Admiralty and Solomon Islands.

19. CYSTODIACEAE

Phylogeny and evolution: Historically Cystodium was placed among the tree ferns in Dicksonioideae, but morphology and molecular analyses place it clearly in Polypodiales. It had been in Lindsaeaceae, but that is not warranted on the basis of morphology and phylogenetics; it is often found in analyses to have a more isolated position among the early polypods.

These terrestrial ferns have creeping to erect stems with long hairs. Petioles are densely hairy at base and have two vascular bundles separated by an X-shaped bundle in crosssection. Blades are bipinnate-pinnatifid

Cystodium sorbifolium, fiddlehead and rhizome scales, Solomon Islands (CC) [19]

Lace-fern family

These are terrestrial or epiphytic ferns with creeping, scaly rhizomes. Rhizome scales are basally attached and not clathrate. Petioles have a single vascular bundle. Blades are variable in shape, simple or one to four times pinnate, decompound or finely divided, glabrous when mature. Some species of Odontosoria have spiny, vining rachises. Veins are free or anastomosing, the areoles, when present, without included veinlets. Sori form terminally, often uniting several vein ends near the margin. Indusia are basally and laterally attached, opening towards the margin. Receptacles are usually hairy, the sporangia have three-celled stalks and a defined annulus. Spores are trilete, rarely monolete, globose to ellipsoid, smooth or variously ornamented. Gametophytes are green and heart-shaped.

Etymology: Saccoloma is derived from Greek σάκκο (sacco), a bag and λόμα (loma), an edge or border.

Rowan-fern family

20. LINDSAEACEAE

Cystodium sorbifolium, sorus detail, Solomon Islands (CC) [19]

Cystodium sorbifolium, Solomon Islands (CC) [19]

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POLYPODIALES

Odontosoria chinensis, Tahiti [20]

FERNS

Tapeinidium moorei, New Caledonia [20]

Lindsaea orbiculata, Hong Kong [20]

Nesolindsaea kirkii, Seychelles [20]

Odontosoria deltoides, sori, New Caledonia [20]

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Lindsaea quadrangularis subsp. antillensis, Guadeloupe [20]

POLYPODIALES

FERNS

Himalayas and southern Japan. They are found mostly in wet, lowland or montane forests but sometimes grow in more open habitats. Phylogeny and evolution: Lindsaeaceae were traditionally associated with Dennstaedtiaceae, but instead they form one of the early branching lineages in Polypodiales, a sister lineage to all other polypods. Because Dennstaedtiaceae form a clade with Pteridaceae, Lindsaeaceae are not closely related to that family. Genera and species: Lindsaeaceae consist of six genera with about 220 species: Lindsaea (c. 175), Nesolindsaea (2), Odontosoria (c. 20), Osmolindsaea (7), Sphenomeris (1) and Tapeinidium (19). Uses: The leaves of Odontosoria chinensis were collected in Hawaii to make a red dye. Etymology: Lindsaea was named for Jamaican surgeon John Lindsay (1750–1803), who was the first to describe germination of fern spores.

21. DENNSTAEDTIACEAE Bracken family

These terrestrial ferns have usually longcreeping, sometimes ascending erect rhizomes (Blotiella) that are hairy and often also scaly. Petioles are placed on the upper side of rhizomes, with one U-shaped or two parallel, upwardly merging vascular bundles. Blades are often large, bi- to tripinnatepinnatifid, and often hairy. Veins are free, forked or pinnate, rarely merging and then without included veinlets. Sori are formed marginally or close to the margins, are linear or round and terminate one or many veins.

Indusia are linear or cup-like, fixed basally and laterally, opening towards the margins, or the margin is reflexed over the sorus. Spores are trilete or monolete, tetrahedral or reniform. Gametophytes are green and heart-shaped.

Genera and species: Dennstaedtiaceae consist of ten genera with some 240 species: Blotiella (16), Dennstaedtia (c. 70), Histiopteris (c. 7), Hypolepis (c. 50), Leptolepia (1), Microlepia (c. 60), Monachosorum (6), Oenotrichia (2), Paesia (14) and Pteridium (c. 13).

Distribution: Dennstaedtiaceae are a family with a global distribution, species of the genus Pteridium (bracken) occur almost everywhere, except in extremely arid and permanently frozen areas. The diversity of the family is greatest in tropical mountains. Blotiella is most diverse in Africa, Oenotrichia is confined to New Caledonia and Monachosorum is restricted to tropical Asia. By contrast, Histiopteris incisa is widespread, occurring in tropical mountains and in temperate rainforests across the Southern Hemisphere.

Uses: Asian bracken (Pteridium esculentum) is frequently used in Asian cooking, most commonly the young leaves (fiddleheads) are are stir-fried. Starch from the roots is also extracted and made into dumplings considered a delicacy, although they may have a constipating effect. Asian bracken is known to be carcinogenic, so caution should be taken when eating fiddleheads, especially because they are easily confused with other, more toxic bracken species. European bracken (Pteridium aquilinum) produces a dye of various shades of green from the leaf tips, and the rhizome is used in Scotland to make the dark-yellow dye found in some tartans. Dennstaedtia glauca is used as a green manure in the Andes.

Phylogeny and evolution: Dennstaedtiaceae are an old family that were traditionally associated with Lindsaeaceae or Pteridaceae. Molecular analyses place them as sister to Pteridaceae, which together are sister to the ‘eupolypods’ (Aspleniaceae + Polypodiaceae). Pteridium pubescens, New Mexico (DZ) [21]

Etymology: Dennstaedtia is named for German botanist August Wilhelm Dennstädt (1776–1826). Pteridium pinetorum, Finland [21]

Blotiella stipitata, Kenya [21]

Histiopteris incisa, New South Wales, Australia [21]

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POLYPODIALES

FERNS

Hypolepis repens, Guadeloupe [21]

Dennstaedtia punctilobula, New York, USA [21]

22. PTERIDACEAE Ribbon-fern family

Dennstaedtia bipinnata, Mary Selby Botanical Garden, Florida, USA [21]

Sporangia have a vertical interrupted annulus. Spores are trilete, globose or tetrahedral and variously ornamented. Gametophytes are green, heart- or ribbon-shaped and sometimes with filamentous gemmae along the margins. Distribution: Pteridaceae are nearly cosmopolitan with their greatest diversity in dry regions and the wet tropics, but with some taxa extending into higher latitudes.

These terrestrial, epilithic or epiphytic ferns have creeping, ascending or erect rhizomes that are usually scaly (rarely only with hairs). Petioles are hairy or glabrous, have a U-shaped vascular bundle in cross-section and often bear proliferating buds at the base. Blades are monomorphic or dimorphic, simple, pinnate, pedate or decompound, glabrous or covered with hairs and/or scales. Veins are free and forking, flabellate or variously anastomosing and reticulate, the areoles without included veinlets. Sori are formed marginally or along veins and lack a true indusium, although often with a ‘false indusium’, e.g. a modified flap of the leaf margin recurved over the sorus.

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Phylogeny and evolution: Pteridaceae were traditionally variably defined, but molecular studies have helped greatly to redefine this group. The family is monophyletic when the traditional families Adiantaceae, Cheilanthaceae, Parkeriaceae, Platyzomaceae and Vittariaceae are included. Pteridaceae are sister to Dennstaedtiaceae and are composed of five subfamilies (Ceratopteridoideae, Cheilanthoideae, Cryptogrammoideae, Pteridoideae and Vittarioideae), which are discussed below. The family originated in the Late Cretaceous. Genera and species: Pteridaceae consist of about 45 genera, perhaps fewer after generic

recircumscription, with c. 1,150 species. The largest genera are Pteris (c. 300 species) and Adiantum (c. 200 species). The five subfamilies are treated separately below. Uses: The leaves of maidenhair fern (Adiantum capillus-veneris) can be simmered in water for several hours, after which it is boiled into a syrup with sugar called ‘sirop de capillaire’, which can then be mixed with fruit juices to make a refreshing drink. Allosorus pteridioides can be used as a tea substitute. Ceratopteris species are popular aquarium plants, and Ceratopteris cornuta is consumed as a vegetable in Liberia. Fibres from petioles of Adiantum and Pityrogramma have been used by Native Americans to weave black designs in baskets. Many species are grown as ornamental plants, especially species of Adiantum, Pellaea and Pteris, and some species such as Adiantum raddianum, Pteris cretica and P. vittata are commonly naturalised in tropical and temperate regions, especially in urban areas. Etymology: The Greek πτέρης (pteris), a fern, is derived from πτερων (pteron), a feather, in reference to their feathery leaves.

POLYPODIALES

FERNS

22a. PTERIDACEAE SUBFAMILY CRYPTOGRAMMOIDEAE Parsley ferns These terrestrial ferns have creeping or decumbent to nearly erect rhizomes. The rhizome scales are lanceolate, brown and rigid. Leaves are monomorphic (Coniogramme) to strongly dimorphic (Cryptogramma), and then the fertile leaves are more erect with contracted segments, or they are partly dimorphic, with the apical fertile part of the leaf having longer and more slender segments (Llavea). Petioles have one vascular bundle. Blades are one to four times pinnate or two times pinnate-pinnatisect, with the terminal segment similar to the lateral ones, glabrous or sometimes sparsely hairy, sometimes glaucous beneath. Veins are free or anastomosing marginally, the vein ends often being somewhat enlarged. Sporangia are borne on the veins in elongated soral lines, without an indusium, but the sorus is frequently covered by the modified leaf margin. Spores are trilete, angular-globose, verrucate, tuberculate or rugulose. Distribution: These ferns are found in North America, north to Alaska and south to Mexico and Guatemala, southern Chile and adjacent Argentina, throughout Europe, mostly in the north and in mountains, throughout Siberia and the Urals to the Himalayas and East Asia, also in tropical Africa, Java and some Pacific islands. Phylogeny and evolution: Cryptogrammoideae are the first diverging clade in Pteridaceae. They were previously placed in Cheilanthoideae on the basis of superficial

Cryptogramma crispa, Scotland, UK [22a]

morphological similarities, but are not immediate relatives. Cryptogramma occurs around the Arctic, in mountains in the temperate zones and in southern South America, whereas Coniogramme is more a species of humid subtropical lands in the Old World. Llavea cordifolia, endemic to Mexico and Guatemala, was previously not placed in the subfamily, but is now known to belong here as well. Genera and species: Cryptogrammoideae consist of three genera with c. 41 species: Coniogramme (c. 30), Cryptogramma (c. 10) and Llavea (1). Etymology: Cryptogramma is derived from the Greek κρυπτος (kryptos), hidden and γραμμή (grammio), a line, in reference to the linear sorus that is hidden by the reflexed leaf margin.

22b. PTERIDACEAE SUBFAMILY CERATOPTERIDOIDEAE Mangrove ferns These are terrestrial, submerged or floating aquatic ferns. Rhizomes are short, small and erect or stout and creeping. Rhizome scales are thin, few and small or many and large. Petioles have two larger and several smaller or four larger and several smaller vascular bundles. Leaves are partially or completely dimorphic, in Acrostichum once pinnate, the fertile parts covering the entire lower part of the pinna blade, in Ceratopteris the sterile leaves lobed to three times pinnate and fertile leaves contracted, one to five times pinnate. Blades are glabrous, and the veins are

Acrostichum aureum, Seychelles [22b]

reticulate without included veinlets. Sporangia cover the entire lamina (Acrostichum) or form along the veins and covered by a modified marginal indusium (Ceratopteris). Spores are angular, globose, with coarse parallel ridges or with tubercles and papillae. Distribution: This is a pantropical subfamily, usually occurring in flooded or seasonally inundated places or mangroves. Phylogeny and evolution: Difficult to define, Ceratopteridoideae have shifted their morphology as a consequence of adaptation to aquatic habitats. These characters also made the species difficult to place in previous classifications. The genus Ceratopteris was previously placed in the separate family Parkeriaceae, with chromosome numbers and spores showing a distant affinity with Anemiaceae, but the fertile structures show a more clear affinity with Pteridaceae. Acrostichum is a genus that had a broad application in the past, but is now restricted to a few species of semi-aquatic mangrove ferns in the tropics. It was previously believed to be associated with Pteridoideae, but molecular evidence places it with Ceratopteris as sister to Pteridoideae. Genera and species: Ceratopteridoideae consist of two genera with nine species: the large mangrove and swamp ferns Acrostichum (4), and the common fresh water aquatic Ceratopteris (5). Etymology: Ceratopteris is derived from the Greek κέρας (keras), a horn, and πτέρης (pteris), a fern.

Ceratopteris pteridoides, Colombia (MF) [22b]

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POLYPODIALES

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FERNS

Pityrogramma calomelanos, Réunion [22c]

Jamesonia goudotii, Ecuador [22c]

Anogramma leptophylla, Lebanon [22c]

Pteris usambarensis, sori, Kenya [22c]

Taenitis blechnoides, Singapore [22c]

Pteris vittata, Brazil [22c]

22c. PTERIDACEAE SUBFAMILY PTERIDOIDEAE Brakes

absent, but often the sori are covered by the reflexed leaf margin. Spores are trilete, usually angular, globose and variously ornamented.

These terrestrial and epilithic ferns have creeping or erect rhizomes with non-clathrate entire scales or rigid bristles. Petioles have one to four or many (and then usually with two larger) vascular bundles. Leaves can be monomorphic, slightly dimorphic or the fertile leaves can be different from the sterile ones. Blades are simple, trifoliate, or one to five times pinnate, pedately organised or forking from a central point. Veins are free or reticulate without included veinlets. Sori are formed submarginally, joining several vein ends, or along anastomosing veins. The indusium is usually

Distribution: This subfamily occurs throughout the tropics and subtropics of the world, north to the southern USA, southern Europe and East Asia and south to southern South America, Australia and New Zealand. They are uncommon in frost-prone areas.

Christenhusz, Fay & Chase

Phylogeny and evolution: Pteridoideae form with Cryptogrammoideae and Ceratopteridoideae the sister clade to the remainder of the family. They include an expanded Jamesonia (including Eriosorus and Nephopteris) and Pteris, the latter now including Afropteris,

Anopteris, Litobrochia and Neurocallis. Platyzoma, formerly in Platyzomaceae, is also placed in Pteris, although separation as a subgenus is warranted. The relationships between the species of the large genus Pteris need further study. Genera and species: Pteridoideae consist of 15 genera with c. 445 species: Actiniopteris (4), Anogramma (3), Aspleniopsis (1), Austrogramme (5), Cerosora (3), Cosentinia (1), Gastoniella (3), Jamesonia (c. 51, Onychium (c. 10), Pityrogramma (c. 20), Pteris (c. 300), Pterozonium (14), Syngramma (15), Taenitis (c. 15) and Tyronia (4). Etymology: Pteris is Greek for fern.

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Pellaea mucronata, University of California Botanical Garden, Berkeley, USA

[22d]

Doryopteris concolor, Brazil [22d]

22d. PTERIDACEAE SUBFAMILY CHEILANTHOIDEAE Lip ferns These are terrestrial and epilithic ferns, often with adaptations to arid environments. Rhizomes are erect to long-creeping with scales and sometimes hairs. Petioles have one or two vascular bundles. Leaves are undivided or one to five times pinnate, pedately or sometimes palmately compound. The blades are often scaly, sometimes hairy, glandular or glabrous. Veins are usually free or sometimes anastomosing. Sporangia are borne along veins in lines or along the margin and then often covered by a modified marginal indusium. Spores are trilete and often cristate. Distribution: Cheilanthoideae occur throughout the subtropics and tropics, extending into the temperate zones in North America, southern Europe, South Africa, East

Cheilanthes austrotenuifolia, Mt Benia, Western Australia [22d]

Asia and New Zealand. They are especially diverse in the American deserts. Phylogeny and evolution: This subfamily is remarkable in its adaptation to arid conditions, with the leaves being able to revive after desiccation in many species. The lineage forms a natural entity, but the internal generic circumscription is still in great need of study. Molecular work is needed to redefine these genera because two of the best known genera, Cheilanthes and Pellaea in their traditional sense, are widely polyphyletic, and it is possible that all (currently about 25 genera) should be united in a single genus, Hemionitis, the oldest name for this group. The genus Gaga, which received much media attention as it was named for musician Lady Gaga, belongs to the clade that includes Aspidotis, an older name. Genera and species: Cheilanthoideae consist

of c. 310 species in c. 13 genera: Allosorus (c. 50), Aspidotis (24), Bommeria (5), Calciphilopteris (4), Cheilanthes (c. 50), Cheilosoria (c. 50), Doryopteris (c. 40), Hemionitis (8), Mildella (1), Notholaena (c. 30), Pellaea (c. 40), Pentagramma (2) and Pteridella (c. 5). The generic circumscription is far from perfect and needs significant taxonomic and nomenclatural attention because many traditional genera are polyphyletic. The consensus of c. 13 poorly defined genera is an intermediate solution, but it can equally be argued that all are better united into a single genus, with Hemionitis having nomenclatural priority. Both solutions will require large numbers of new combinations. Etymology: Cheilanthes is derived from the Greek χείλος (cheilos), a lip and άνθος (anthos), a flower, in reference to the edge of the pinnules, which form a lip covering the sporangia.

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22e. PTERIDACEAE SUBFAMILY VITTARIOIDEAE Maidenhair and ribbon ferns These are terrestrial, epilithic and epiphytic ferns. Rhizomes are erect, suberect or creeping, sometimes with the leaves widely spaced, sometimes densely clustered. Rhizome scales are thin, ovate-lanceolate and brown, clathrate or not. Leaves are monomorphic or nearly so. Petioles have one or two vascular bundles, which are often short or nearly absent in epiphytic species. Blades are simple, and then entire and linear, sagittate or forked or cleft, or one to six times pinnate, or the petiole divided into two forming a pedate blade, usually glabrous, sometimes pubescent, thin herbaceous or thick and leathery. Veins are simple or forked and free or sparingly anastomosing, sometimes reticulate, but areoles without included veinlets. Sporangia are borne along

Haplopteris ensiformis, Singapore [22e]

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veins in short lines near the margin, often covered by a modified leaf margin (Adiantum) or in simple or branched lines along the veins or immersed in a groove along the midvein. Spores are trilete or monolete, hyaline or not, globose, prominently angled and variously ornamented or smooth. Distribution: Pantropical, with a few representatives in humid temperate regions, north to Alaska and Canada, western Europe, the Himalayas and northeastern Asia, south to southern South America, South Africa, Australia and New Zealand. Phylogeny and evolution: Vittarioideae are composed of the former Vittariaceae plus Adiantum. Apart from Adiantum, they are all epiphytes with finely matted roots, mostly simple blades and sori along the veins or in lateral grooves along the midveins. The association with Adiantum seems odd at first,

Antrophyum boryanum, Réunion [22e]

but they do share some anatomical characters, such as the presence of ‘spicular cells’ in the leaf epidermis. With Cheilanthoideae, Vittarioideae form the crown group in Pteridaceae that together are sister to a clade uniting the other subfamilies. Vittaria in the traditional sense was polyphyletic and has therefore been broken up. Genera and species: Vittarioideae consist of c. 11 genera, with species: Adiantum (c. 200), Ananthacorus (1), Anetium (1), Antrophyum (c. 40), Haplopteris (c. 40), Hecistopteris (3), Monogramma (9), Polytaenium (18), Radiovittaria (5), Scoliosorus (2) and Vittaria (c. 10). It has been debated how many genera should be recognised in Vittarioideae. Etymology: Vittaria is derived from the Latin vitta, a band or ribbon, in reference to the narrowly linear leaves of this genus.

Adiantum capillus-veneris, Sicily, Italy [22e]

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23. ASPLENIACEAE Spleenwort family

These are terrestrial, epiphytic and epilithic (rarely aquatic or climbing) ferns that usually have blackish and wiry roots (rarely fleshy). Their rhizomes are erect, sometimes trunklike or short- to long-creeping, stoloniferous or scandent in some species, branched or not, with lanceolate to linear rhizome scales. The leaves are monomorphic, slightly dimorphic or strongly dimorphic, gemmiferous or not, variously scaly or hairy, brightly coloured when young in several genera. Petioles have (mostly) two vascular bundles. Blades are simple or one to four times pinnate-pinnatifid, in some taxa with conspicuous aerophores along the rachises. Veins are free or anastomosing, reaching the margin or terminating before it (and then often with expanded vein endings), areoles when present usually have no included veinlets. Sori are formed on a flat or raised receptacle, usually along veins on the lower side of the blade, and are often elongate along the vein, placed in vein forks and triangular or circular and placed atop a vein, rarely acrostichoid (covering the entire blade). The indusium can be flat and laterally attached along one (asplenioid) or both sides of the vein (diplazioid) or in the axils of veins and the indusia merged in v- or j-shapes, or hood-like and attached at the base of the sporangium, or reniform and atop a vein, or the indusium can be absent. Sporangia are (long-)stalked, the stalks can be up to three cells wide. Spores are not or occasionally chlorophyllous, monolete, variously ornate. Gametophytes are green, superficial and heart-shaped. Distribution: This family is globally distributed and can be found in all areas except in permanently frozen or arid areas.

Phylogeny and evolution: Also known as ‘eupolypods II’, Aspleniaceae have been expanded to include in this clade the former families Athyriaceae, Blechnaceae, Onocleaceae, Thely pteridaceae and Woodsiaceae. These families are all closely related and share the usually linear (sometimes circular) sori organised along the veins with a laterally attached indusium (when present), the blackish, wiry roots and two vascular bundles in the petioles. Aspleniaceae split from Polypodiaceae in the Late Jurassic, c. 104–107 million years ago. Aspleniaceae diversified into their major subdivisions during the Late Cretaceous and Early Tertiary. Genera and species: Aspleniaceae include 23 genera and c. 2,780 species. The family is divided into eight subfamilies (Asplenioideae, Athyrioideae, Blechnoideae, Cystopteridoideae, Diplaziopsidoideae, Rhachidosoroideae, Thelypteridoideae and Woodsioideae). They are discussed separately below because they are sometimes treated at the family level. The largest genera are Asplenium (c. 700), Athyrium (c. 200), Blechnum (c. 250), Diplazium (c. 350) and Thelypteris (c. 1,100). Uses: The young shoots or fiddleheads of the ostrich fern, Onoclea struthiopteris, are commonly consumed in North America. Onoclea orientalis is also used for this purpose in Asia. The young leaves and croziers of the ‘vegetable fern’, Diplazium esculentum, are commonly consumed in stir-fries or in salads in tropical Asia and the Pacific. The leaves are mildly toxic, but no adverse health effects are known. Young fiddleheads of the painted fern Athyrium nipponicum can also be eaten after being thoroughly boiled to leach out the toxins. The young leaves of Asplenium viviparum are cooked and eaten in New Zealand, and in Asia the young shoots of nest fern (A. nidus) are sometimes consumed. Young croziers of Stenochlaena palustris are eaten in Southeast Asia, and the rhizomes of Blechnum orientale have been eaten in Malaysia. The rhizomes of Onoclea and Cystopteris can be peeled and roasted, but these should be

considered only a famine food. The long stems of Stenochlaena palustris produce a durable fibre after submersion in salt water. They are used in the manufacture of fish traps or are twisted into rope. The cortex of the stem of Blechnum cyatheoides was used in Hawaii to produce a red dye. A number of species are cultivated as garden or houseplant ornamentals. Etymology: From Old French esplen, in turn derived from the Greek σπλην (splin), a spleen, in reference to the former use of spleenwort to cure spleen and liver problems.

23a. ASPLENIACEAE SUBFAMILY CYSTOPTERIDOIDEAE Bladder ferns These terrestrial ferns have blackish, wiry roots that emerge from creeping to suberect, branching, scaly rhizomes. Their leaves are monomorphic and bear scales that are sometimes hair-like. The blades are thinly herbaceous, (one or) two to three times pinnate-pinnatifid and deltate or lanceolate in outline, and occasionally bear bulbils that grow into new plants. Veins are free and terminate at the margin. Sori are formed on a hardened receptacle, along veins on the lower side of the blade and are round or slightly elongate. The indusium is hood-like, attached at the base of the sporangium, or absent. Spores are monolete, echinate, tuberculate or broadly folded. Gametophytes are green and heart-shaped with glandular hairs on the wings. Distribution: Cystopteridoideae are distributed across temperate areas of the Northern Hemisphere and in mountains in the tropics, extending south into the Andes, South Africa, tropical Asia, Australia and New Zealand. Phylogeny and evolution: The genera were in past classifications rarely placed together. Gymnocarpium was usually treated as allied to the dryopteridoid ferns, whereas Cystopteris was usually associated with the athyrioids or woodsioids. Gymnocarpium was found to be sister to a clade uniting Cystopteris and

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POLYPODIALES

Cystopteris fragilis, Yorkshire, England, UK [23a]

Gymnocarpium dryopteris, Michigan, USA [23a]

Gymnocarpium fedtschenkoanum, Hortus botanicus, Leiden, the Netherlands [23a]

Acystopteris, and this trio is sister to the rest of Aspleniaceae (‘eupolypods II’). Cystoathyrium, a native of China, has not been recently found and is probably extinct. It is placed here tentatively. Hybrids between Cystopteris and Gymnocarpium are known.

broadest at the base and gradually taper to the apex. Veins are free, terminating before reaching the hyaline margins. Sori are elongate and formed on a flat receptacle on the lower side of the leaves along one side of veins with a laterally attached indusium. Spores are monolete, echinate, tuberculate or broadly folded. Gametophytes are heart-shaped, superficial and green.

Etymology: Rhachidosorus is derived from the Greek ράχης (rhachis), a spine or ridge, and σορός (soros), a coffin or urn, in reference to the placement of the sori.

Genera and species: Cystopteridoideae consist of four genera with c. 30 species: Acystopteris (3), Cystoathyrium (1), Cystopteris (c. 20) and Gymnocarpium (7). Etymology: From Greek κυστός (kystos), a bladder or pouch, referring to the indusium that looks like an inflated bladder, and πτέρης (pteris), a fern.

23b. ASPLENIACEAE SUBFAMILY RHACHIDOSOROIDEAE Lacquer ferns These terrestrial ferns have creeping, usually unbranched, scaly rhizomes. Their scales are clathrate and entire. Leaves are monomorphic and sparsely scaly. Blades are herbaceous and two to three times pinnate-pinnatifid; they are

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Distribution: Rhachidosoroideae occur in East Asia, often in forests on limestone. Phylogeny and evolution: Plants are similar to and difficult to distinguish from Athyrioideae (to which they were often referred in the past), and the subfamily also shares characters with Asplenioideae. Rhachidosoroideae diverged from their nearest relatives c. 90 million years ago, before Blechnoideae diverged from Athyrioideae. Genera and species: Rhachidosoroideae consist of the single genus Rhachidosorus with four to eight species, depending on taxonomic concept.

23c. ASPLENIACEAE SUBFAMILY DIPLAZIOPSIDOIDEAE Glade ferns These terrestrial ferns have fleshy, rarely wiry, roots that grow radially from erect or shortcreeping, usually unbranched, scaly rhizomes. Rhizome scales are entire, not clathrate and lanceolate. Leaves are glabrous or bear filiform scales. Blades are once pinnate, herbaceous or fleshy; the apex is gradually reduced or similar to lateral pinnae. Venation is free or anastomosing toward the hyaline margins, but areoles, when present, lack included veinlets; the free vein-endings are slightly expanded and raised. Sori are borne singularly along one side of the vein (asplenioid), or two sori are formed back to back along the same vein (diplazioid) with the glabrous or glandular indusium attached laterally along the vein. Spores are monolete and folded with erose

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crests. Gametophytes are heart-shaped and glandular-hairy on the wings. Distribution: This subfamily has a disjunct distribution in eastern North America (Homalosorus) and in East and tropical Asia and some Pacific islands (Diplaziopsis). Phylogeny and evolution: Diplaziopsidoideae are similar to Athyriaceae in many respects, and before molecular data were available all species were placed in the genus Diplazium. The family shares many characters with Hemidictyum, which was originally also placed here, but DNA studies have shown that this would make the family polyphyletic with regards to Asplenioideae. One species, Diplazium flavoviride, also belongs to this lineage because it shares characters with Diplaziopsis, but no molecular data are yet available for this species.

Etymology: Diplaziopsis is derived from the Greek, διπλάσιος (diplasios), double, for its double sori, and -opsis, appearance, in reference to its resemblance to Diplazium.

23d. ASPLENIACEAE SUBFAMILY ASPLENIOIDEAE Spleenworts

the veins, rarely two sori are formed back to back along both sides of the vein, and the indusium is laterally attached along the veins and is glabrous. Sporangia are long-stalked and single rowed. Spores are monolete, reniform, usually with sharp ridges or broad folds or wings. Gametophytes are green and heart-shaped. Distribution: This subfamily occurs nearly globally, except for permafrosted or extremely arid regions.

Genera and species: Diplaziopsidoideae consist of two genera with six species: Diplaziopsis (5) and Homalosorus pycnocarpos.

These are terrestrial and epiphytic ferns with blackish wiry roots. Their rhizomes are scaly, short- to long-creeping or erect and usually unbranched. Rhizome scales are entire, lanceolate and clathrate, sometimes with glandular margins. Leaves are monomorphic or slightly dimorphic, occasionally bearing bulbils that grow into new plants. Petioles are variably coloured, often glossy, with two vascular bundles. Blades are undivided (simple) or one to four times pinnate, usually tapering gradually towards the apex, sometimes with a terminal pinna similar to the lateral. Veins are free or reticulate, areoles, when present, not including veinlets. Sori are elongate along one side of

Homalosorus pycnocarpos, Brooklyn Botanical Garden, New York, USA [23c]

Asplenium marinum, Scotland, UK [23d]

Asplenium septentrionale, Finland [23d]

Phylogeny and evolution: Among ferns Asplenioideae are unusual in showing diversification in both tropical and temperate regions, and there are as many epiphytic as terrestrial species. The family is readily distinguishable by their linear sori with indusia attached to one side of the vein. The numerous segregate genera of Asplenium are now generally not accepted because they made Asplenium polyphyletic, and numerous intergeneric hybrids were frequently observed in the wild. The wider

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POLYPODIALES circumscription resulted in a genus with great diversity in morphology and habitat preference. Only Hymenasplenium, which is sister to Asplenium, is maintained, although some authors have suggested that even this genus should be united with Asplenium. The third genus Hemidictyum has always been difficult to place. It was formerly treated as Asplenium or Diplazium and was considered allied to Thelypteridoideae or Diplasiopsidoideae. Molecular studies have shown that it is sister to the remaining Aspleniaceae, and even though it could be maintained in its own subfamily, it is here united with an expanded Asplenioideae as characters are shared. Hemidictyum diverged from the remaining Asplenioideae in the Late Cretaceous. A great number of segregate genera have been proposed (e.g. Camptosorus, Ceterach, Diellia, Loxoscaphe, Phyllitis, Pleurosorus, Thamnopteris etc.), but intergeneric hybrids are commonly encountered. Most segregate genera were found to be embedded in Asplenium in molecular studies. Asplenium australasicum, Moorea, French Polynesia [23d]

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Genera and species: Asplenioideae consist of four genera with c. 716 species: Asplenium (c. 700), Desmophlebium (1), Hemidictyum (1) and Hymenasplenium (c. 15).

These terrestrial ferns have blackish, wiry roots that emerge from short- to long-creeping or scandent, suberect or erect rhizomes that bear lanceolate, non-clathrate, hairy scales. Their leaves are usually conspicuously hairy, and the hairs are often whitish, acicular (curved at the tip) and unicellular, sometimes combined with various types of multicellular hairs (stellate, forked etc.). Young developing leaves are often covered in mucilage, with conspicuous aerophores (breathing tubes) protruding through the

mucilage, which are persistent when leaves are mature. The leaves are monomorphic or subdimorphic, the fertile leaves then contracted, sometimes bearing bulbils. Petioles have two vascular bundles, rarely more, and are not persistent on the rhizome. Blades are simple or one to three times pinnate-pinnatifid, with or without reduced pinnae at the base, the pinna bases often bearing a conspicuous aerophore. Veins are free, sometimes terminating before reaching the margin, merging below a sinus in lobed pinnae, or anastomosing and sometimes with a conspicuous fish-bone pattern (meniscioid); areoles can have included veinlets, but not always. Sori are formed on top of veins and are circular or elongate, indusiate or exindusiate, on a flat receptacle. Indusia are lateral and reniform when present. Sporangia are stalked, the stalks three cells wide in the middle. Spores are monolete, brown and achlorophyllous, reticulate, echinate or sharply crested. Gametophytes are green and heartshaped, often somewhat elongate and without a distinct midrib, frequently bearing hairs or stalked glands.

Hemidictyum marginatum, Brazil [23d]

Phegopteris hexagonoptera, North Carolina [23e]

Etymology: Asplenium is derived from Greek σπλην (splin), a spleen, in reference to the former medicinal use of spleenwort to cure spleen and liver diseases.

23e. ASPLENIACEAE SUBFAMILY THELYPTERIDOIDEAE Marsh ferns

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Macrothelypteris torresiana, St Petersburg, Florida, USA [23e]

Thelypteris limbosperma, Ireland [23e]

Thelypteris hydrophila crozier showing pneumatophores, Guadeloupe [23e]

Woodsia ilvensis, Nauvo, Finland [23f]

Distribution: This is a nearly cosmopolitan family, with the greatest diversity in (sub-) tropical montane regions. Phylogeny and evolution: Thelypteridoideae have the largest number of species in Aspleniaceae, in which they are deeply embedded. Having unusual hairs and placement of indusia, and sometimes more than two vascular bundles in the petiole, they are not a good morphological match with the remainder of Aspleniaceae, but these are derived characters and the subfamily clearly belongs here. They diverged from other Aspleniaceae c. 80 million years ago. Gener ic deli mit ation in Thelypteridoideae is still disputed, but we opt for a broad generic circumscription subsuming Pseudophegopteris into Phegopteris and

including Cyclosorus and Meniscium in an expanded Thelypteris (if segregated Meniscium has priority over Cyclosorus, causing nomenclatural havoc). Future studies may show that more genera need to be recognised, but with our current knowledge of the group, this reduction in generic names seems the most stable solution. Genera and species: Thelypteridoideae consist of three genera with c. 1,130 species: Macrothelypteris (11), Phegopteris (26) and Thelypteris (c. 1,100). Etymology: Thelypteris is derived from the Old Greek θελης (thelys), female or fruitful, and πτέρης (pteris), a fern, possibly referring to the superficial similarity to the lady fern (Athyrium filix-femina, Athyrioideae)

23f. ASPLENIACEAE SUBFAMILY WOODSIOIDEAE Cliff ferns These are terrestrial ferns that often grow on rocky substrates. Their roots are wiry and blackish as in all other Aspleniaceae. Their rhizomes are scaly, short-creeping or erect and usually not branched. The rhizome scales are lanceolate and not clathrate. Leaves are monomorphic and closely spaced and bear both scales and hairs. The two-stranded petioles are usually persistent on the rhizomes, but are sometimes articulate. Blades are once pinnate to twice pinnate-pinnatifid, usually broadest in the middle, with or without reduced pinnae at base, and apices are reduced to a non-conforming terminal segment. Veins are free and do not reach the margin, and vein endings are usually

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POLYPODIALES expanded, forming hydathodes. Sori are placed dorsally along veins on flat receptacles, and are round and indusiate. Indusia are basal and composed of a series of segments or are globose and sack-like. Sporangium stalks are two or three cells wide in the middle. Spores are monolete, brown and achlorophyllous and variously ornate. Gametophytes are green and heart-shaped.

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23g. ASPLENIACEAE SUBFAMILY ATHYRIOIDEAE Lady ferns

Etymology: Woodsia is named for English botanist Joseph Woods (1776–1864).

These are terrestrial or rarely aquatic ferns with blackish, wiry roots. Their rhizomes are short- to long-creeping, suberect or erect, sometimes branching and scaly. Rhizome scales are lanceolate and usually not clathrate. Leaves are green or tinged pink, red or variously coloured and are usually monomorphic or slightly dimorphic. They can have bulbils, hairs or scales. Petioles have usually two (rarely more) vascular bundles. Blades are simple or one to three times pinnate-pinnatifid, the apex usually pinnatifid and different than lateral pinnae. Veins are usually free, usually terminating before they reach the margins, and often forming hydathodes, sometimes the veins are anastomosing, but areoles formed by this reticulation lack included veinlets. Sori form on a flat receptacle. They are usually elongate, sometimes rounded, and are placed atop a vein or along one (asplenioid) or both sides of the vein (diplazioid), or in the axils of veins and the indusia merged in V- or J-shapes (athyrioid). Sori are rarely marginal; the indusia are usually laterally attached, vaulted or flat. Sporangia are stalked, the stalks two or three cells wide in the middle. Spores are

Athyrium otophorum, private garden, Kingston upon Thames, Surrey, UK [23g]

Athyrium asplenioides, sori, New York, USA [23g]

Distribution: These occur mostly in the Arctic and mountains of the Northern Hemisphere, in open rocky places, forests or arid areas, with one species (Woodsia montevidensis) extending along the Andes into temperate South America. Phylogeny and evolution: Woodsioideae form an isolated lineage in Aspleniaceae, and, in spite of their superficial resemblance to Cystopteridoideae, they are not the immediate relatives of this subfamily. They do occur in similar habitats, but resemblance is due to convergence. They are clearly divided into an Old World and a New World clade. Genera and species: Woodsioideae consist of the single genus Woodsia, with c. 35 species.

Diplazium proliferum, sori, Réunion [23g]

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monolete, achlorophyllous, plain or variously ornate. Gametophytes are green and heartshaped, glabrous or with glandular hairs on the wings. Distribution: This subfamily can be found worldwide, except for extremely arid regions and glaciated or permafrost areas. They are most diverse in the Asian subtropics. Phylogeny and evolution: These four genera have long been associated and were usually included with Cystopteris, Diplaziopsis and Woodsia in the family Woodsiaceae. That assembly was found to be polyphyletic with regards to other lineages in “eupolypods II” and were hence divided. Athyrioideae form a clade with Blechnoideae, which diverged c. 75 million years ago. Anisocampium is sometimes segregated from Athyrium, making the latter genus paraphyletic. Genera and species: Athyrioideae consist of four genera with c. 580 species: Athyrium (c. 216), Deparia (10) and Diplazium (c. 350). Etymology: Athyrium is derived from the Greek αθυρος (athyros), without a door, an ‘atrium’, in reference to the chamber-like, open sorus.

Diplazium sibiricum, Sweden [23g]

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Blechnum ryanii, Guadeloupe [23h]

23h. ASPLENIACEAE SUBFAMILY BLECHNOIDEAE Hard ferns These terrestrial and climbing ferns have blackish wiry roots that emerge from erect, sometimes trunk-like or short- to longcreeping, sometimes scandent, branched or unbranched, sometimes stoloniferous, scaly rhizomes. Rhizome scales are lanceolate to linear, not clathrate. Unfolding leaves are usually colourful, often orange, red or pinkish (green in Onoclea), sometimes covered in mucilage, and are monomorphic or strongly dimorphic, bulbiferous or not and usually scaly and sometimes hairy. Petioles have two large vascular bundles and smaller bundles on the upper side of the petiole; in Onoclea these are starch-filled at the base and sometimes persistent for many years forming a protective sheath. The blades are pinnatifid or one to two times pinnate-pinnatifid, usually once pinnate, the rachis vining in Salpichlaena, the base with or without reduced pinnae, the apical pinna conform or not, pinnae in some species with conspicuous aerophores. Veins are free, simple or forked and only occasionally anastomosing along midveins or fully anastomosing, the areoles in this way lacking included veinlets, the free veins reach the margin or terminate

Woodwardia radicans, private garden, England, UK [23h]

before it. Sori are formed on a flat or raised conical receptacle, elongate along one side of veins parallel to the midvein or round and terminating a vein. The sori are usually indusiate, but are rarely acrostichoid and exindusiate; the indusia are flat and lateral, with the opening facing the midvein, usually elongate, sometimes triangular. Sporangia are stalked, the stalk one to three cells wide. Spores are monolete, not or occasionally chlorophyllous but usually brown, smooth or variously ornate. Gametophytes green, heartshaped, sometimes with glandular hairs on the wings. Distribution: Blechnoideae are cosmopolitan, except for arid, polar and high alpine regions. Phylogeny and evolution: Blechnoideae comprise two subclades, Onoclea s.l. (sometimes treated as Onocleaceae) and Woodwardia+Blechnum s.l. Despite some differences in fertile structures these are closely related and share many morphological characters. Onoclea diverged from the Woodwardia+Blechnum clade at the end of the Cretaceous, some 70 million years ago. The former Onocleaceae include five species that were traditionally divided into two genera, which are at their extremes easily distin-

guishable, the ostrich ferns (often placed in Matteuccia) and the sensitive fern (Onoclea sensibilis), but the other three species are intermediate and have been placed into two additional not very distinctive genera, each genus thus representing one or two species. These species are better united under the single genus Onoclea. The remaining clade has a deep split corresponding roughly with the two Hemispheres: Woodwardia is the first branching, exclusively found on the northern continents. The second clade includes Blechnum, with its segregates Brainea, Doodia, Pteridoblechnum and Sadleria all embedded in it, and Stenochlaena as sister to this clade, but with Salpichlaena and Telmatoblechnum placed with Stenochlaena rather than with core Blechnum. Further phylogenetic research is needed to study character evolution in the morphologically diverse genus Blechnum. Genera and species: Blechnoideae include six (or more) genera with c. 290 species: Blechnum (c. 250), Onoclea (5), Salpichlaena (2), Stenochlaena (c. 15), Telmatoblechnum (2) and Woodwardia (c. 20). Etymology: Blechnum is derived from βλήχνον (blechnon), an ancient Greek word for fern. Plants of the World

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Onoclea struthiopteris, Finland [23h]

Blechnum (Sadleria) cyatheoides, Royal Botanic Gardens, Kew, UK [23h]

Stenochlaena palustris, Singapore [23h]

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Blechnum spicant, Twickel, the Netherlands [23h]

Blechnum paschale, Easter Island [23h]

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24. POLYPODIACEAE Polypody family

sometimes ribbon-like or elongate and straplike to filamentous, glabrous or hairy. Distribution: Polypodiaceae occur worldwide. This is the largest family of ferns, and they occupy most habitats. They are absent from polar, high alpine and arid areas.

This family consists of terrestrial, epiphytic and epilithic, sometimes climbing ferns with erect or long- or short-creeping rhizomes that branch or not. The rhizomes are sometimes viny or climbing, sometimes have stolons or tubers, are often fleshy and are usually scaly. Rhizome scales are clathrate or opaque, hairy or glabrous, basally attached or peltate. Their leaves are variable, monomorphic or dimorphic, simple or one to four times pinnate-pinnatifid, short- or long-petiolate, the petioles cleanly abscising or persistent. Petioles have two to several vascular bundles that are usually arranged in a half-circle, a ring or a U-shape in cross-section, sometimes swollen at the base or with an articulation. Blades can be glabrous, hairy, scaly or glandular, sometimes with proliferous buds, or they can be pedate, flabellate or forked. Veins are free, simple, forked or pinnate, or variably anastomosing or reticulate, areoles, when present, having included veinlets or not, sometimes with thickened endings (hydathodes) before reaching the margin. Sori are superficial or impressed, discrete and round or confluent and acrostichoid (covering all or part of the fertile leaf lamina below), rarely linear and following the veins, indusiate or exindusiate. Indusia, when present are usually centrally attached and reniform, but can be variably laterally attached, reniform or lunate, oblique or round or elongate and linear. Sporangia are stalked, the stalk with up to three cells, the capsule with a vertical annulus. Spores are monolete, ellipsoidal to globose and alate, cristate, verrucate, tuberculate, rugose or echinate, chlorophyllous and green or achlorophyllous and brown. Gametophytes are green and usually heart-shaped, but

Phylogeny and evolution: Polypodiaceae are the broad family formerly recognised as several families placed in ‘eupolypods I’. They include the majority of extant fern diversity. They are especially diverse in the understory of rainforests and as epiphytes on rainforest trees, and they diversified in response to the development of angiosperm rainforests during the Cretaceous. Subfamilies Didymochlaenoideae, Hypodematioideae, Dryopteridoideae, Lomariopsidoideae and Tectarioideae form a grade to the almost exclusively epiphytic or epilithic Oleandroideae, Davallioideae and Polypodioideae. However, epiphytic species also occur in other subfamilies, suggesting that epiphytism has evolved several times independently in Polypodiaceae. Genera and species: Polypodiaceae consist of c. 76 genera with c. 4,070 species, with the largest genera being Dryopteris (c. 400), Elaphoglossum (c. 750), Grammitis (c. 700), Polystichum (c. 370) and Tectaria (c. 250). The family is divided into eight subfamilies (Didymochlaenoideae, Davallioideae, Dryopteridoideae, Hypodematioideae, Lomariopsidoideae, Oleandroideae, Polypodioideae and Tectarioideae), which are sometimes treated as separate families and are therefore treated and discussed separately below. Uses: The tender young leaves of Arthromeris wallichiana are cooked as a vegetable in Nepal. Leaves of some Pyrrosia species are eaten as a vegetable in China. The young fronds of many species of Dryopteris and Polystichum are cooked and eaten in Asia, but caution has to be taken because they are mildly toxic, even when boiled. Rhizomes of Dryopteris expansa and Polystichum munitum were eaten by Native Americans and reportedly taste like sweet potatoes, but

they were only eaten when little else was available. Rhizomes of several Polypodium species, especially P. glycyrrhiza and P. vulgare, contain ostadin, a steroidal saponin that has a sweet taste. They are licorice-flavoured and were commonly chewed by many native North American tribes as an appetiser, especially by children who would not eat. In the past, common polypody, P. vulgare, was employed to flavour tobacco. Rumohra adiantiformis is cultivated on a large scale for the cut-flower industry as the fern leaf in many bouquets of cut flowers. The fibre of Nephrolepis hirsutula is sometimes used to manufacture hats, mats and baskets. Boston fern (Nephrolepis exaltata ‘Bostoniensis’) is a common house plant. This and several other Nephrolepis are frequently planted as ornamentals in the tropics, where they sometimes naturalise. Didymochlaena truncatula and Davallia tyermannii are also frequently grown as houseplants, and many others are used as garden ornamentals. Gametophytes of Lomariopsis lineata are sometimes sold as peculiar aquarium plants, under the German name ‘Susswassertang’. Etymology: Polypodium is derived from the Greek πολύς (polys), many, and ποδιών (podion), feet; in reference to the ‘manyfooted’ branching rhizomes.

24a. POLYPODIACEAE SUBFAMILY DIDYMOCHLAENOIDEAE Mahogany ferns These large terrestrial ferns have erect, thick, scaly rhizomes, with persistent petiole bases. The scales are long, narrow and almost hair-like. Leaves are bipinnate and long-petiolate; petioles have several vascular bundles arranged in a half-circle. Pinnae are articulate to the rachis and more or less similar in size and shape, somewhat rectangular in outline. Veins are free, forked, with endings thickened before reaching the margin. Sori terminate a vein and are often somewhat sunken in the blade, forming bumps on the upper side of the leaf. Indusia are elongate, centrally attached along a line and opening on either

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POLYPODIALES side. Sporangia are long-stalked. Spores are monolete, ellipsoidal to globose, tuberculate and echinate. Gametophytes are heart-shaped and glabrous. Distribution: The single species is found throughout the tropics, often on wet clayey substrates near streams in forests. There is possibly an additional species in Madagascar, but this is yet to be confirmed. Phylogeny and evolution: Didymochlaenoideae are generally treated as related to Dryopteridoideae, but inclusion there would render the latter paraphyletic. In some studies Didymochlaena is sister to Hypodematioideae, but including it in that clade makes Hypodematioideae difficult to define morphologically. Didymochlaena is the first branching clade in Polypodiaceae. Didymochlaenoideae are distinguished from Hypodematioideae in having erect rhizomes, hair-like rhizome scales, bipinnate leaves, with all pinnae of the same shape, not gradually narrowing and confluent towards the apex, veins with thickened ends terminating before the margin, sori terminating a vein, with long and narrow elongate indusia attached along a central line, opening towards the sides and having echinate spores. Didymochlaena truncatula, Brazil [24a]

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Genera and species: This subfamily consists of a single genus Didymochlaena, with one (D. truncatula) or maybe two species. Etymology: Didymochlaena is derived from Greek δίδυμος (didymos), twin, and χλαινα (chlaina), a cloak, in reference to indusia that open on two sides.

24b. POLYPODIACEAE SUBFAMILY HYPODEMATIOIDEAE Bigfoot ferns These are usually terrestrial or epilithic ferns with long- or short-creeping, thick, sometimes fleshy, scaly rhizomes. Rhizome scales are sometimes hairy. Leaves are two to four times pinnate-pinnatifid and long-petiolate. Petioles are often swollen at the base and have two large and several smaller vascular bundles organised in a U-shape in cross-section. Blades and pinnae are gradually reduced and confluent towards the terminal segments. Veins are free, simple, forked or pinnate and end at the margin. Sori are impressed and indusiate, the indusia reniform to nearly round and basally (or also slightly laterally) attached, opening towards the margin, glabrous or hairy. Sporangia are longstalked with stalks one to three cells wide and have a vertical annulus. Spores are monolete, ellipsoidal, coarsely verrucate or tuberculate.

Gametophytes are green and heart-shaped and glandular hairy on the margins. Distribution: They occur mainly in tropical Asia, east to Polynesia, with one species extending into tropical East Africa and Madagascar. Phylogeny and evolution: This subfamily is often associated with Dryopteridoideae, but merging the two would render the latter polyphyletic. The two genera that compose Hypodematioideae have been variously treated in the past: Hypodematium was considered to be associated with the athyrioid ferns, and Leucostegia was previously placed in Davalliaceae. They are, however, each other’s closest relatives. Didymochlaena was found as sister to these two genera, but usually without strong support. It is possibly not directly related. Didymochlaena is here treated in a separate subfamily. Genera and species: Hypodematioideae consist of two genera and 16 species: Hypodematium (13) and Leucostegia (3). Etymology: Hypodematium is derived from the Greek υπό (ypo), under, and δεματίων (demation), a bundle, referring to the hairs on the sori.

Arachniodes aristata, sori, Tahiti [24c]

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Polystichum setiferum, crozier, private garden, Hengelo, the Netherlands [24c]

Elaphoglossum feei, Guadeloupe [24c]

Polybotrya osmundacea, sori, Brazil [24c]

Elaphoglossum crinitum, Botanical Garden, Berlin-Dahlem, Germany [24c]

Polystichum aculeatum, Yorkshire, UK [24c]

Mickelia nicotianifolia, Guadeloupe [24c]

Elaphoglossum peltatum, Mary Selby Botanical Garden, Sarasota, Florida, USA [24c]

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24c. POLYPODIACEAE SUBFAMILY DRYOPTERIDOIDEAE Buckler ferns This subfamily consists of terrestrial and epiphytic ferns. Their rhizomes are creeping or erect, sometimes vining and scaly. Rhizome scales are not clathrate. Leaves are monomorphic or dimorphic, simple or one to four times pinnate-pinnatifid, and petioles have many vascular bundles arranged in a circle. Blades are glabrous, hairy, scaly or glandular. Veins are free, variably anastomosing or reticulate, forking or pinnate, and areoles, when present, can have included veinlets or not. Sori are usually rounded with reniform or round, peltate indusia, or the indusia are absent. In tribe Elaphoglosseae the sori are acrostichoid, i.e. covering the entire lamina of the fertile leaf, without indusia. Sporangia are shortstalked, the stalks with three rows of cells. Spores are monolete, reniform and winged. Gametophytes are green and heart-shaped. Distribution: This is an almost cosmopolitan subfamily, absent from arid and frozen areas. Several species are colonisers on oceanic islands. The subfamily is diverse and includes terrestrial plants, climbers and epiphytes. Phylogeny and evolution: In the traditional sense, this subfamily included a number of genera that have been demonstrated not to

Cyclopeltis presliana, sori, Singapore Botanic Garden [24d]

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belong here, but when Cyclopeltis, Didymochlaena, Dracoglossum, Lomariopsis, Nephrolepis and the genera now in Tectarioideae are excluded and the remaining genera previously in Lomariopsidaceae (e.g. Bolbitis, Elaphoglossum) are included they form a clade that is difficult to define morphologically. Dryopteridoideae are divided into two tribes: Elaphoglosseae, with acrostichoid fertile laminae, and Dryopterideae, the true buckler ferns. Mickelia nicotianifolia was found to have the largest known genome of any leptosporangiate fern. Genera and species: Dryopteridoideae consist of c. 27 genera with c. 2,000 species: Arachniodes (c. 110), Arthrobotrya (3), Bolbitis (c. 60), Ctenitis (c. 120), Cyclodium (10), Cyrtomidictyum (4), Dryopolystichum (1), Dryopteris (c. 400), Elaphoglossum (c. 600–800), Lastreopsis (41), Lomagramma (19), Maxonia (1), Megalastrum (c. 40), Mickelia (10), Olfersia (2), Parapolystichum (5), Phanerophlebia (9), Pleocnemia (23), Polybotrya (35), Polystichopsis (30), Polystichum (c. 370), Pseudotectaria (8), Rumohra (1–8), Stigmatopteris (28) and Teratophyllum (12). Etymology: Dryopteris is derived from the Greek δρυς (drys), oak and πτέρης (pteris), fern, describing the shape of the pinnae of some species.

Nephrolepis biserrata, Brazil [24d]

24d. POLYPODIACEAE SUBFAMILY LOMARIOPSIDOIDEAE Sword ferns These are terrestrial, epilithic and epiphytic ferns. Their rhizomes are variable, often creeping and scrambling over rocks or climbing up trees, sometimes erect, stout and short, in Nephrolepis often with stolons (runners forming buds from which new plants grow), sometimes also with scaly tubers. Leaves are monomorphic or dimorphic, and petioles have two large vascular bundles and several smaller ones arranged in a U-shape. Blades are simple and proliferous at the apex (in Dracoglossum) or once pinnate and not proliferous (bipinnate in some cultivars of Nephrolepis). Pinnae, when present, are articulate to the rachis. Veins are free, parallel, simple and forked or pinnate, sometimes meniscioid-reticulate with included veinlets and in Nephrolepis ending before the margin in thickened hydathodes. Sori are discrete, orbicular, with peltate round or reniform indusia or exindusiate, placed in one to four rows on each side of the costa, in one species of Nephrolepis linear and terminating many veins, or sporangia acrostichoid. Spores are bilateral, monolete, ellipsoid or globular, variously winged or ornamented. Gametophytes are green and heart-shaped or ribbon-like, glabrous or long-hairy.

Dracoglossum plantagineum, Guadeloupe [24d]

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FERNS

Tectaria griffithii, Malaysia [24e]

Hypoderris brownii, Puerto Rico, USA [24e]

Distribution: This is a pantropical subfamily of understory vegetation in rainforests and on rocks along small streams.

Ancient Greek λωμα (loma), an edge or border, in reference to the sori that run in parallel with the leaf margin.

Phylogeny and evolution: Lomariopsidoideae previously included Bolbitis, Elaphoglossum, Lomagramma and Teratophyllum, genera that are now known to belong to Dryopteridoideae. Dracoglossum (previously treated as a species of Tectaria) is most closely related to Lomariopsis, a relationship that has only recently been discovered. Nephrolepis is variously included or excluded, but it shares the articulate leaflets, which are diagnostic for this group. Nephrolepis was traditionally placed in Davallioideae, a result not supported by molecular and morphological analyses. Nephrolepis evolved in the Eocene in the forests of the Laurasian tropical belt, from where two main lineages have dispersed and became isolated, one in the Neotropics and the other in AsiaAustralasia, from where they spread to other tropical regions.

24e. POLYPODIACEAE SUBFAMILY TECTARIOIDEAE Button ferns

Genera and species: Lomariopsidoideae consist of four genera with c. 75 species: Cyclopeltis (7), Dracoglossum (2), Lomariopsis (c. 45) and Nephrolepis (20). Etymology: Lomariopsis is named for its resemblance to Lomaria, a synonym of Blechnum. Lomaria is derived from the

Button ferns are terrestrial with creeping to erect, scaly rhizomes. Their rhizome scales are much longer than wide and not clathrate. Leaves are monomorphic or dimorphic, and petioles have several vascular bundles organised in a ring or semi-circle. Petioles are sometimes articulate (Arthropteris). Blades are simple or pinnate to bipinnate-pinnatifid, sometimes decompound, usually with stubby jointed hairs, and midribs bear proliferous buds in some species. Veins are free or (more often) anastomosing or fully reticulate, usually with included veinlets. Sori are of variable shape and position, usually dorsal or terminal on the veins, indusiate or not, round, oval or (rarely) linear and opening towards the margin, rarely following veins and covering the entire lamina eventually. Indusia, when present, are round, reniform or lunate, sometimes oblique. Sporangia are stalked, and spores are ellipsoidal with wing-like folds or are variously ornamented. Gametophytes are green and more or less heart-shaped.

Distribution: Tectarioideae are pantropical, extending into the subtropics in Asia. Phylogeny and evolution: A number of genera traditionally associated with Tectaria (e.g. Ctenitis, Dryopsis, Lastreopsis, Lomariopsis, Pleocnemia, Pseudotectaria etc.) are not closely related and do not belong in Tectarioideae. Arthropteris is not closely related to Oleandra or Nephrolepis as previously assumed, but is sister to the rest of Tectarioideae. This clade of terrestrial ferns is sister to the predominantly epilithic and epiphytic Oleandroideae, Davallioideae and Polypodioideae. Genera and species: Tectarioideae consist of seven genera with c. 315 species: Aenigmopteris (5), Arthropteris (22), Draconopteris (2), Hypoderris (3), Pteridrys (10), Tectaria (c. 250) and Triplophyllum (23). Etymology: The derivation of Tectaria is obscure, but it is possibly derived from the Greek τεκτα (tekta), mason, because the venation pattern of some species resembles masonry.

24f. POLYPODIACEAE SUBFAMILY OLEANDROIDEAE Stilt ferns These scandent epilithic or epiphytic, rarely terrestrial ferns have long-creeping, frequently

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Oleandra annetii, Seychelles [24f]

branching rhizomes covered with peltate rhizome scales. Leaves are simple, articulate to a short knob-like outgrowth of the rhizome. Petioles have two larger and several smaller bundles organised in a semi-circle. Blades are simple, rounded at the base and acute to acuminate at the apex. Veins are parallel, forked, free or occasionally anastomosing, ending in thickened hydathodes near the margins. Sori are round and form singly on upper vein branches, rarely nearly terminally on the veins, indusiate. Indusia are reniform to nearly round and attached by a broad sinus. Sporangia have stalks that are long and three cells wide, and they emerge mixed with hairs. Spores are monolete, ellipsoid, with prominent wing-like folds and various ornamentations. Gametophytes are green, heart-shaped and often hairy. Distribution: This clade is pantropical, with only a few representatives in the Americas and Africa. Phylogeny and evolution: The subfamily is closely related to Polypodioideae, with which they share several characters. Traditionally Arthropteris was also included, but this genus is now placed in Tectarioideae. Genera and species: Oleandroideae consist of the single genus Oleandra with c. 15–20 species, mostly in the Asian tropics.

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Oleandra sibbaldii, sori, Tahiti [24f]

Etymology: Oleandra is derived from Nerium oleander (Apocynaceae) because of the superficial resemblance of the type species, Oleandra neriiformis, to leaves of oleander.

Distribution: Davallioideae occur throughout the Palaeotropics extending into the Asian subtropics, with a disjunct population in the Canary Islands. They are most diverse in tropical Asia.

24g. POLYPODIACEAE SUBFAMILY DAVALLIOIDEAE Hare’s-foot ferns

Phylogeny and evolution: The subfamily in the strict sense (excluding Leucostegia, now in Hypodematioideae, and Gymnogrammitis, now part of Selliguea, Polypodioideae) has only two genera. There were several other genera traditionally accepted in this group, but they have been found to be embedded in one or other of the two genera now recognised.

These are epiphytic and epilithic ferns with long-creeping, branching, densely scaly rhizomes. Rhizome scales are peltate and cover the entire rhizome, making it look like the foot of an animal. Leaves are usually monomorphic, rarely dimorphic, and petioles have two larger and three smaller vascular bundles. Blades are simple or one to three times pinnate-pinnatifid and are hairy or glabrous when mature. Veins are free, simple, forked or pinnate, terminating before reaching the margin. Sori are formed marginally or away from the margin but always terminating veins. They are triangular or round, with a cup-shaped, reniform or lunate indusium, rarely forming a confluent marginal sorus. Sporangia are long-stalked, the stalk threecelled and the capsule with a vertical annulus. Spores are monolete, ellipsoid, winged, cristate or variously ornamented. Gametophytes are green, heart-shaped with short, occasionally branched hairs.

Genera and species: Davallioideae consist of two genera with about 45 species: Davallia (c. 30) and Davallodes (c. 15). Etymology: Davallia is named for English botanist Edmond Davall (1763–1798), who bequeathed his herbarium to his friend James E. Smith, who named this genus for him.

24h. POLYPODIACEAE SUBFAMILY POLYPODIOIDEAE Polypodies These mostly epiphytic and epilithic ferns are rarely found terrestrially (and then mostly in temperate regions). Rhizomes

POLYPODIALES

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Davallia mariesii, Royal Botanic Gardens, Kew, UK [24g]

Pyrrosia lingua, Jardin des Plantes, Paris, France [24h]

Microsorum scolopendrium, Réunion [24h]

Davallia solida, Tahiti [24g]

Platycerium coronarium, Singapore [24h]

Pleopeltis polypodioides, St Petersburg, Florida, USA [24h]

Loxogramme lanceolata, Kenya [24h]

Grammitis serrulata, Guadeloupe [24h]

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POLYPODIALES are creeping, often long and branching, scaly or (rarely) glabrous, sometimes short and stubby or suberect. Rhizome scales are clathrate or opaque. Most species (except Grammitis) have leaves that leave a clean scar or knob after falling off. Leaves are monomorphic or dimorphic with petioles that have a variable number of vascular bundles arranged in a U-shape. Blades are simple, pinnatifid or once pinnate, rarely more divided, sometimes pedate, flabellate or forked, glabrous or with hairs or scales. Veins are free, anastomosing or reticulate, sometimes the areoles with included veinlets. Sori are formed underneath the lamina or (rarely) marginally, usually rounded or elliptic, sometimes sunken in the lamina or conf luent to completely acrostichoid, never indusiate, but sori sometimes covered with scales. Sporangia are short or longstalked, with three cells; the capsule has a vertical, interrupted annulus. Spores are monolete, bean-shaped, white, yellow, green or brown, or trilete, thin-walled, globosetetrahedral and chlorophyllous, and are variously ornamented. Gametophytes are green and heart-shaped, broader than long, often with a prominent midrib and often with

Polypodium vulgare, Turku, Finland [24h]

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various hair-types, or the gametophytes are strap-like to filamentous, sometimes with proliferating buds. Distribution: Polypodioideae are a cosmopolitan subfamily of evergreen ferns with the greatest diversity in the tropics. Like most ferns, they are absent from arid or frozen areas. Phylogeny and evolution: Polypodioideae are sister to Davallioideae and Oleandroideae, with which they share their preference for growing epiphytically and epilithically. Polypodioideae differ from those subfamilies in their lack of an indusium. Polypodioideae are divided into five tribes: Loxogrammeae including the peculiar Loxogramme; Drynarieae with Drynaria and Selliguea; Platycerieae, with Pyrrosia and Platycerium (stag horn ferns); Microsoreae, with Microsorum, Goniophlebium and relatives; and Polypodieae, including the true polypods and Grammitis. Grammitis differs in having green, trilete spores and persistent petiole bases and often filiform gametophytes. Previously these ferns were treated in a separate family

Grammitidaceae with a great number of genera, but they are better treated as the single genus Grammitis in subfamily Polypodioideae. The genera in Polypodioideae are still in need of further study and recircumscription. Genera and species: Polypodioideae include about 29 genera, sometimes more depending on taxonomic preference, with c. 1,600 species: Campyloneurum (55), Dendroconche (2), Dictymia (2), Drynaria (27), Goniophlebium (27), Grammitis (c. 700), Lecanopteris (13), Lemmaphyllum (13), Lepidomicrosorium (27), Lepisorus (c. 90), Leptochilus (c. 50), Loxogramme (44), Microgramma (25), Microsorum (c. 40), Neocheiropteris (c. 9), Paragramma (5), Pecluma (30), Phlebodium (4), Phymatosorus (31), Platycerium (16), Pleopeltis (c. 35), Pleurosoriopsis (1), Podosorus (1), Polypodium (c. 70), Pyrrosia (c. 70), Selliguea (c. 145), Serpocaulon (43), Thylacopteris (2) and Tricholepidium (14) Etymology: Polypodium is derived from the Greek πολύς (polys), many, and ποδιών (podion), feet, refering branching, creeping rhizomes.

Grammitis nanodes, Kenya [24h]

GYMNOSPERMS The first seed plants were gymnospermous in the sense that ovules did not develop inside an ovary, but rather were ‘naked’ on the sporophylls (fertile leaves). The ovules develop on modified leaves or scales, often fused into coneshaped structures. The earliest seed-like fossils are known from Upper Devonian deposits, c. 385–359 million years ago. All seed plants are heterosporous, i.e. they produce two kinds of spores, microspores (pollen grains) and megaspores (ovules in the ovaries). Hence, it is assumed that the ancestors of seed plants must have been heterosporous, but heterospory in seedless vascular plants (ferns and lycopods) is mostly restricted to aquatic lineages, which have evolved heterospory as a secondary trait. The fossil record of gymnosperms includes many distinctive taxa that do not belong to the four modern lineages, including seed-bearing trees with a fern-like vegetative morphology, the seed ferns or pteridosperms. It has been suggested that angiosperms are derived from a larger group of gymnosperms that were much more heterogeneous than extant gymnosperms and undoubtedly were not a single clade. However, all extant gymnosperms are sister to the angiosperms. Early molecular results (e.g. Hasebe et al. 1992) were the first to demonstrate that the extant group was a clade, but most workers at the time considered that the sparse sampling of the early DNA studies made the results somewhat unconvincing. However, all major DNA studies to date have demonstrated this relationship, so it has slowly gained acceptance. Prior to DNA studies, it was thought likely that each of the four extant clades would be related to different groups of sporebearing taxa, thus making the concept of “gymnosperm” similar to that of “dicot”

in referring to a stage of evolution (a grade) rather than a monophyletic group. As indicated above, the stillprevailing notion is that gymnosperms in the broadest sense, including fossil taxa, are not monophyletic and thus the term refers to a grade. However, use of “gymnosperm” is nonetheless made acceptable (unlike “dicot”) by the fact that all extant taxa form a clade. Given that this was an unexpected result, how the other (all fossil) taxa are related to these is more speculative than previously thought. Therefore, until such time as definitive results have been obtained, we advocate continued use of “gymnosperm” (whereas the term “dicot” must be abandoned). Seeds are thought to have evolved to keep plant embryos from drying out. The development of seeds allowed plants to be less dependent on water for fertilisation, and enclosure of female gametes in an ovule increased this success rate. Formation of seeds also allowed storage of nutrients that were packed together with the embryo. These seeds could germinate in periodically more hospitable environments. Early seed plants (gymnosperms) still depended on the wind to bring pollen to the ovaries, but with the development of flowers, animals became involved in this process, although some modern gymnosperms are known to be insect-pollinated as well. Insects, especially beetles, were attracted by flowers to eat from fleshy structures (tepals) and pollen, but soon more specialised associations between flowers and their pollinators developed, resulting in the enormous diversity of flowers and pollinators we see today. Diversif ication of angiosperms resulted in a loss of gymnosperm diversity. At present the slightly more than 1,000 species of extant gymnosperms are

arranged in 12 families. Even though the group was more diverse in the fossil record than today, they occur throughout the world, forming dominant stands in boreal forests, subtropical swamps, tropical mountains, cloud and rain forests, coastal habitats and semi-deserts. Against the background of their paucity of species numbers, they exhibit a great deal of heterogeneity and specialisation, including at least one (half-)parasite (Parasitaxus) and species adapted to unusual substrates (e.g. ultramafic rocks in New Caledonia) and conditions (e.g. waterlogged conditions, as for Taxodium and Retrophyllum), arid regions and annually deep-frozen boreal forests. The general manner in which they are described leads one to conclude that they are a relict group, which has been collectively excluded from many habitats by the angiosperms, but this is misleading and ignores the fact that, like most groups of ferns and angiosperms, there has been a recent radiation of species adapted to modern environmental conditions. In fact, in the more archaic cycads, nearly all extant species and genera are the products of a radiation that took place in the past 20 million years. Although they clearly exhibit ancient morphologies, the modern species are not “living fossils”, except perhaps for Ginkgo biloba, the only extant member of its clade with a long fossil history. In terms of their inter-relationships, cycads are sister to the rest, followed successively by ginkgo and the conifers (the term conifer is often used for the pines and their relatives, but cones are also found in cycads), in which “gnetoids” (Gnetaceae, Ephedraceae and Welwitschiaceae), formerly thought to be transition groups between gymnosperms and angiosperms, are collectively sister to Pinaceae (see results of Chaw et al.

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Here we use the classif ication of Chase & Reveal (2009), who did not use a formal name for the gymnosperms, stating that, given the speculative nature of the hypothesised relationships of the fossil gymnosperms and their still-likely grade status, such formal taxonomic recognition would be unwise and premature. Each of the four major groups was given the rank of subclass, although it must now be considered that Gnetidae should now be treated as three orders in Pinidae. The angiosperms were given equal rank to each of these, as the single subclass Magnoliidae. As Chase & Reveal (2009) pointed out, past classifications that recognised the angiosperms as several subclasses in a single class (such as the system of Cronquist) forced other members of the land flora and the various groups of aquatic plants (“algae”, not a monophyletic concept) to be pushed into ever higher ranks, leaving “no room at the top”.

General references Byng JW. 2015. The gymnosperms handbook. A practical guide to extant families and genera of the world. Plant Gateway, Hertfort. Chase MW, Reveal JL. 2009. A phylogenetic classification of the land plants to accompany APG III. Botanical Journal of the Linnean Society 161: 122–127. Chaw SM, Parkinson CL, Cheng Y, Vincent TM, Palmer JD. 2000. Seed plant phylogeny inferred from all three plant genomes: monophyly of extant gymnosperms and origin of Gnetales from conifers. Proceedings of the National Academy of Sciences (USA) 97: 4086–4091. Chaw SM, Zharkikh A, Sung HM, Lau TC, Li WH. 1997. Molecular phylogeny of extant gymnosperms and seed plant evolution: analysis of nuclear 18S rRNA sequences. Molecular Biology and Evolution 14: 56–68. Christenhusz MJM, Reveal JL, Farjon A, Gardner MF, Mill RR, Chase MW. 2011. A new classification and linear sequence of extant gymnosperms. Phytotaxa 19: 55–70. Eckenwalder JE. 2009. Conifers of the world. Timber Press, Portland. Farjon A. 2010. A handbook of the world’s conifers. Brill, Leiden. Foster AS, Gifford EM. 1974. Comparative morphology of vascular plants. Freeman, San Francisco. Hasebe M, Kofuji R, Ito M, Kato M, Iwatsuki K, Veda K. 1992. Phylogeny of gymnosperms inferred from rbcL gene sequences. Botanical Magazine (Tokyo) 105: 673–679.

2000, a study that has created a great deal of controversy). Other studies using various methods of analysis and/or downweighting of particular categories of DNA positions that change frequently have produced other topologies, but the one most favoured and most commonly obtained is with the gnetoids as sister to Pinaceae, the so-called “gnepine hypothesis”. Given that the previously most favoured hypothesis for gnetoids was as the sister group to the angiosperms, the “gnepine hypothesis” is revolutionary and will still require some years of additional investigation before it becomes more widely accepted. Relative to what we know of these taxa morphologically, such a relationship is bizarre and calls into question relationships hypothesised for fossil groups such as Bennettitales (Cycadeoidales) and “seed ferns” (e.g. Archaeopteris) on morphological g rounds. Sim i larly unex pected results of DNA studies are those for Psilotum and Equisetum, which were long held to be only distantly (and non-exclusively) related to ferns, but they have been clearly shown to be part of the fern clade, calling into question relationships proposed for the former to the rhyniophytes (the earliest vascular plants known) and the latter to Calamites and related sphenophylls (Foster & Gifford 1974).

Etymology: The word gymnosperm is derived from γυμνός (gymnos), naked, and σπέρμα (sperma), seed, referring to the seeds that are formed on the sporophylls without a covering. Part of the gymnosperms are called conifers, from κώνος (conos), a cone, and φέρουν ( feroun), to bear, referring to the cones in which seeds and pollen are formed.

The tallest trees in the world are a gymnosperm, Sequoia sempervirens, Muir Woods, California, USA

Maarten Christenhusz holding cones of Pinus coulteri, one of the largest cones of any pine, Rancho Habitat dominated by a gymnosperm, Pinus Santa Ana Botanical Garden, California, USA palustris, Green Swamp, North Carolina, USA

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CYCADALES

GYMNOSPERMS

CYCADALES Cycads are an ancient group that is sister to all other living gymnosperms. Fossil cycads are known from the Lower Permian of China, c. 275 million years ago, with their greatest diversity during the Jurassic/Cretaceous periods. It is thought that cycads arose from an extinct Palaeozoic lineage of seed ferns, but this hypothesis needs re-examination in the light of the DNA-based assessments of their relationships. Cycads radiated and dispersed during the Permian and early Mesozoic, leading to the Jurassic sometimes being referred to as the ‘age of cycads’, during which bennettites (cycadeoids), cycads, ginkgos and conifers dominated the vegetation of the world. The extant families (Cycadaceae and Zamiaceae) do not have such an extremely long fossil history, but most extant genera can be recognised from early Tertiary deposits (c. 50–60 million years old). Fossil genera of Cycadaceae date back to the Permian, but the extant genera of Zamiaceae evolved since the end of the Cretaceous, thus rejecting the role of dinosaurs in producing modern cycad diversity and the designation of any extant species as a living fossil.

25. CYCADACEAE Sago family

These are unisexual plants with a subterranean or emergent trunk clothed with persistent leaf bases and new leaves formed in flushes. Young parts of the plants are hairy. The leaves are pinnate and not coiled when emerging, but the leaflets emerge in a circinnate way (coiled

Cycas revoluta, female cone, California, USA [25]

with the tip in the centre, like watch springs) and are not articulate to the midrib. The lower leaflets are usually reduced to paired rigid thorns. Male sporophylls (fertile leaves) are arranged in a cone. Female sporophylls are free, not forming cones, consisting of a linear stalk and an expanded apical lobe, usually bearing more than two (up to eight) ovules. Sperm is free-swimming. Seeds have a hard inner and a fleshy outer seed coat. Distribution: This family occurs in tropical Asia, Melanesia, Fiji, Tonga, Australia, Madagascar and coastal tropical East Africa. Pollen is eaten by beetle larvae, and pollination is generally via insects, although some wind pollination may also occur. Most species have a brightly coloured sarcotesta

Cycas seemannii, New Caledonia [25]

(seed coat) and are dispersed by animals, but some coastal species like Cycas rumphii and C. seemannii have floating seeds that are dispersed by sea currents; these species have a wider distribution as would be expected for this mode of dispersal. Phylogeny and evolution: Cycas is the oldest extant genus of cycads, with fossils dating back to the Permian of China and the Eocene of Japan, and molecular estimates of its divergence from the lineage leading to all other extant cycads date to the early Jurassic. In this sense, at least Cycas is a living fossil, although this has been claimed for Cycadales as a whole. Unexpectedly, a molecular clock study demonstrated that none of the species in Cycas and the other cycad genera is older than five million years.

Cycas revoluta, male cone, Irvine, California, USA [25]

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CYCADALES

GYMNOSPERMS

Microcycas calocoma, female cone, Montgomery Botanical Center, Miami, Florida, USA [26]

Dioon edule, female cone, St Petersburg, Florida, USA [26]

Ceratozamia hildae, Matthaei Botanical Garden, Ann Arbor, Michigan, USA [26]

Stangeria eriopus, male cone, Helsinki Botanical Garden, Finland [26]

Lepidozamia peroffskyana, female cones, Royal Botanic Gardens, Sydney, Australia [26]

Encephalartos woodii, male cones, Royal Botanic Gardens, Kew, UK [26]

Genera and species: Cycadaceae include the single genus Cycas, which has c. 91–107 species.

26. ZAMIACEAE

circinnate vernation). Male and female sporophylls (fertile leaves) are fused into cones. Pollen cones are soon shed, but seed cones persist for one to several years. Sperm is free-swimming. Seeds have a hard inner seed coat and a fleshy outer layer, aiding dispersal by animals.

Coontie family

Uses: Starch from the pith of many Cycas species is used to make sago in Asia, but has to be carefully washed to leach out toxins. All untreated parts of cycads are extremely poisonous to humans. Cycas revoluta is a popular house and garden plant. Cultivation of various Cycas species is common throughout the tropics and subtropics. Etymology: Cycas is derived from the Greek κυκας (kykas), a word first used by Theophrastus, thought to be a scribal error for κούκας (koikas), meaning ‘palm trees’, the accusative plural of koix, a word from an unknown pre-Greek language. 74

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Distribution: This family is patchily distributed in tropical America, Sub-Saharan Africa and Australia. These are unisexual plants with subterranean or emergent, simple or irregularly branched trunks that are clothed with persistent leaf bases. New leaves are formed in flushes. Leaves are pinnately compound (but bipinnate in Bowenia); the leaves are not coiled, except in Bowenia and Stangeria (the latter with

Phylogeny and evolution: Stangeria is peculiar in its circinnate vernation, resembling a fern, and it was originally described as one. It was placed with Bowenia in Stangeriaceae, both sharing this feature. Molecular phylogenetic studies have shown these two genera are embedded in Zamiaceae.

GINKGOALES

GYMNOSPERMS

Extant species diversity is the result of a recent radiation within the past five million years, and Zamiaceae should therefore not be considered living fossils, even though some are remarkably similar to fossil taxa. Genera and species: Zamiaceae include nine genera with c. 200 species: Bowenia (2), Ceratozamia (27), Dioon (15), Encephalartos (65), Lepidozamia (2), Macrozamia (c. 30), Microcycas (1), Stangeria (1) and Zamia (c. 55).

Uses: Young seeds of Dioon edule are ground and cooked into tortillas. Seeds of some Encephalartos species are also eaten in South Africa, and the exudate from cones is eaten by children and birds. Zamiaceae leaves are used for decoration, especially in some religious ceremonies in Central America. Nearly extinct: Encephalartos woodii is known only from a single male plant from which cuttings are growing in botanic gardens.

It is extinct in the wild and cannot be reintroduced in the absence of a female plant. The oldest specimen is in the Temperate House of the Royal Botanic Gardens, Kew. Etymology: Zamia is derived from the Latin ‘nuces zamiae’, in translation of Pliny the Elder; this is an erroneous transcription of the phrase ‘nuces azaniae’, referring to pine nuts, probably from Classical Greek αζάινειν (azainein), to dry.

GINKGOALES This order, which originated c. 265 million years ago, occurred world-wide during the Mesozoic. Some authors have hypothesised that they were derived from Palaeozoic pteridosperms, but the morphology of these Carboniferous Ginkgo-like plants is difficult to interpret. Leaves resembling Ginkgo are known from Permian fossils onwards.

27. GINKGOACEAE Maidenhair-tree family

These are unisexual deciduous trees up to 30 m, with irregularly furrowed grey bark. They branch irregularly with long shoots and brachyblasts (stubby short shoots) at regular intervals, each bearing a cluster of leaves. Leaves are fan-shaped, with flabellate venation (radiating out from the petiole), and are slightly fleshy, light green, turning bright yellow in autumn, and deciduous. Male cones are borne on short catkin-like shoots. Pollen is spherical, and sperm is free-swimming. Seeds are formed on Ginkgo biloba, male, Royal Botanic Gardens, Kew, UK [27]

short leaf-like shoots, obovoid to ellipsoid, and c. 2 cm in diameter, yellow to orange, glaucous, with an apical scar, maturing in a single season, usually one (rarely two) per peduncle. The outer seed-coat softens and gives off a foul odour of butyric acid when ripe. Distribution: Ginkgo biloba is native to China, but its occurrence in the wild is uncertain. It is reported to occur naturally in mountain valleys in Zhejiang Province, but because this area has seen human inhabitation for some 1,500 years it is plausible that its persistence is due to ancient cultivation near Buddhist monasteries. The great majority of ginkgos have been planted as ornamental trees, and the species is nearly cosmopolitan. Hardy to -30˚C, it is frequently planted in hemiboreal, temperate and subtropical areas around the world. Phylogeny and evolution: The fossil record shows Ginkgo to have been widespread, diverse and abundant in the Mesozoic. Because Ginkgo biloba, female cones, Ann Arbor, Michigan, USA [27]

nearly identical plants are known from fossils some 200 million years old, the single extant species is often referred to as a living fossil. It is sister to the conifers plus gnetoids. Genera and species: Ginkgo biloba is the sole species in its order (Gingkgoales), family (Ginkgoaceae) and genus (Ginkgo). It is a relict of a once diverse and widespread lineage of plants. Uses: Fresh or canned seeds (with the soft outer layer removed) are a delicacy in East Asian cuisine. Due to their high levels of tolerance to pollution ginkgos are commonly planted along roads and in city parks. Six Ginkgo trees near the blast centre of the atomic bomb in Hiroshima (August, 1945) resprouted without deformation and are still alive today. Etymology: Ginkgo is derived from the Chinese 銀杏 (yínxìng), meaning ‘silver apricot’. The same characters are used for this tree in Japan, but there they are read as ‘ginkyō’. This was how Engelbert Kaempfer (1712), the first Westerner to describe this species in 1690, transcribed its name. Kaempfer’s name was misread by Linnaeus (1753), who erroneously changed the y into a g and published the genus as Ginkgo, which became the accepted name, albeit difficult to pronounce. Plants of the World

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WELWITSCHIALES

Welwitschia mirabilis, male cones with pollinator in Namibia (FF) [28]

GYMNOSPERMS

Welwitschia mirabilis, female cones, Namibia (FF) [28]

Welwitschia mirabilis, female, Namibia (FF) [28]

WELWITSCHIALES This order is known from the fossil record in which there is a seedling of c. 110 million years old. It was once more widespread, pollen being known from North America, Portugal and Brazil.

28. WELWITSCHIACEAE Tumbo family

Tumbos are dioecious plants with short woody, unbranched, cup-shaped stems that widen to a concave disc up to 1 m across with a long taproot. The two (rarely three) strapshaped leaves grow from a basal meristem throughout the life of the plant (estimated to be at least 1,000 years in some individuals), the leaves dying at the tip and fraying. These remarkable leaves have a subparallel venation that occasionally anastomoses or terminates 76

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blindly. From the woody stem, near the leaf bases, small branches arise that bear either male or female cones. Male cones are terminal in groups of two or three on each branch. Female cones consist of a single ovule enclosed in an integument and another layer derived from two confluent primordia with two bracts. There is one seed per cone, which has a wing and is dispersed by wind. Seeds germinate only when water is available, but seedlings are susceptible to fungi, making establishment from seed difficult in cultivation. The two cotyledons photosynthesise for 1.5 years, after which they wither away and are replaced by two leaves. Distribution: This family has two disjunct populations, one in northern Namibia, the other in southern coastal Angola. Phylogeny and evolution: A fossil seedling called Cratonia cotyledon from northeastern

Brazil has a similar vasculature to that of Welwitschia and is perhaps 114–112 million years old. Other fossils with putative relationships to Welwitschia have been found in the same area. Genera and species: Welwitschiaceae include a single genus with a single species, Welwitschia mirabilis, which is divided into two subspecies: W. mirabilis subsp. mirabilis in Angola and W. mirabilis subsp. namibiensis in the southern part of its range. The subspecies differ in characters of the male cones. Etymology: Welwitschia was named by Joseph Hooker for its discoverer, Austrian explorer and botanist Friedrich Martin Josef Welwitsch (25 February 1806–20 October 1872), who, when he discovered it in Angola named it Tumboa, after its local name. Welwitschia has been conserved over Tumboa.

GNETALES

GYMNOSPERMS

GNETALES This order sometimes includes Welwitschiales and Ephedrales, but they are here restricted to the single family Gnetaceae. They have an estimated age of c. 160 million years in most studies, although there is a probable gnetalean fossil of c. 260 million years old.

29. GNETACEAE Emping family

drupe-like; they are enclosed in a red, orange or yellow, usually fleshy false seed coat, with two cotyledons. Distribution: This family occurs in tropical regions, the Amazon Basin, tropical West Africa, India, Southeast Asia and Malesia.

These are unisexual lianas, sometimes trees, that have stems with swollen nodes. Leaves are opposite, petiolate, without stipules, simple, the margins entire, the venation pinnate and apices usually acuminate (driptips), resembling leaves of angiosperms. Both male and female strobili are compound, spike-like, terminal or lateral structures (megastrobili), sometimes emerging from old stems. Each spike consists of a straight axis above a basal pair of opposite, connate bracts, the axis bearing three to six superposed cupules, each containing male or female strobili. Male strobili consist of a stamen and a bract. Female strobili consist of an ovule with two integuments and a bract. Seeds are Gnetum gnemon, seeds, Singapore [29]

Phylogeny and evolution: Gnetaceae may have evolved some 250 million years ago, but the current radiation diverged during the Oligocene and Miocene, late in the history of this ancient lineage. The leaves and fertile structures are angiosperm-like. Nonetheless, DNA studies have shown that Gnetaceae (with Welwitschiaceae and Ephedraceae) are more closely related to Pinaceae than to angiosperms, and hence they are placed here next to the conifers. Genera and species: Gnetaceae consist of the single genus Gnetum with c. 30–35 species. Uses: Gnetum gnemon is cultivated commercially in Indonesia, where the kernels of the large nutritious seeds are beaten flat and fried, becoming the popular snack called ‘emping’.

The young leaves, flowers and fruits are used as vegetables, eaten raw, boiled or roasted. Fibres from the bark provide durable cordage for, for example, fishing nets, rope and bags. The wood is used for paper and house construction. Topical application reduces biting by mosquitoes, and enzymic inhibition prevents insect predation of foliage, which may be applicable in pest control. Scleroderma sinnamariense, a fungus usually associated with Gnetum gnemon, produces an edible fruiting body. Gnetum gnemon is frequently planted as a shade tree and has been used for reforestation of dryland habitats. The trees are sometimes interplanted on farms to provide living stakes for the cultivation of yams. The leaves of Gnetum africanum, are commonly consumed as a vegetable throughout Africa, locally called fumbwa. It is not cultivated, but leaves are gathered from the wild, cut into small strips, boiled and mixed with palm oil or peanut butter. Etymology: The name Gnetum is derived from Maluku or Malay gnemon utan, following the description of the plant by Rumphius, Herbarium Amboinense 1: 183–184, plates 71–73. 1741.

Gnetum gnemon, Singapore [29]

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EPHEDRALES

Ephedra californica, male cones, California, USA [30]

GYMNOSPERMS

Ephedra equisetina, female cones at the time of pollen transfer, Royal Botanic Gardens, Kew, UK [30]

Ephedra americana, mature female cones bearing seeds, Copenhagen Botanical Garden, Denmark [30]

EPHEDRALES The distinctively ridged pollen of Ephedrales is found in the fossil record at least since the Late Triassic. It is sometimes included under Gnetales, but here it is used for the single family Ephedraceae.

30. EPHEDRACEAE Jointfir family

are enclosed by a pair of fused bracteoles that become fleshy or leathery; these are shed with the seed. Female cones have one or two seeds that are yellow to dark brown and have two cotyledons. Distribution: This family occurs in North America, western South America, Mediterranean Europe, North Africa and warm temperate Asia, usually in arid habitats.

These are dioecious (or sometimes monoecious) shrubs and trailing vines with photosynthetic, green, round, jointed branches. Leaves are mostly non-photosynthetic, scale-like, simple, opposite or in whorls of three. They are connate at the base to form a sheath and superficially resemble the sheath-like leaves of Equisetum. Male or female cones are formed singly or in whorls at nodes. Opposite or whorled membranous bracts each subtend a small cone. Ovules 78

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Phylogeny and evolution: Ephedraceae evolved before the early Cretaceous, when they comprised at least two genera. The extant genus Ephedra dates back to the Cretaceous, making the extant species relicts, that were well adapted when semi-arid climates expanded across the World during the Oligocene. Genera and species: Ephedraceae consist of the single extant genus Ephedra, which has c. 40 species.

Uses: In many native cultures where Ephedra occurs it is used for medicinal purposes, such as treatment for cough, poor circulation and allergies. This is because the plants are rich in tannins and often the alkaloid ephedrine. It is commonly applied in herbal treatments and is an ingredient of modern cold and allergy medicines (usually as pseudephedrine). It is also used as a dietary supplement in energy drinks and weight-loss preparations. Ephedrine is not present in the New World species, and the psychotropic properties ascribed to Mormon tea (E. funerea) remain uninvestigated. Etymology: Ephedra is a Greek name given by Pliny to the horsetail, which in turn is derived from έφεδρος (ephedros), ‘sitting upon’, from επί (epi), on, and έδρα (hedra), a seat, probably referring to the segments that sit upon each other.

PINALES

GYMNOSPERMS

PINALES Fossils assigned to Pinales have been dated to c. 155 million years ago, but molecular clock estimates date this order to over 200 million years. The order consists of the single family Pinaceae, which were formerly widespread and now dominant in some parts of the Northern Hemisphere.

31. PINACEAE Pine family

These bisexual, evergreen and deciduous trees, occasionally shrubs, are resinous and aromatic in all parts. Terminal branches are radially symmetrical, lateral branches are well developed and similar to leading shoots or are reduced to short shoots. Leaves are simple, needle-like to linear, and sessile to

short petiolate. They are borne singly and then spirally arranged on long shoots or in fasciculate tufts on short shoots. Male cones are axillary, solitary or clustered, and ovoid to ellipsoid or cylindrical. Sporophylls are overlapping, bearing two pollen sacs. Female cones are compound, axillary, solitary or grouped, and scales are overlapping and free from the subtending bracts for most of their length. Each scale bears two ovules on the upper side. Seeds are winged, the wing free from subtending bracts. The number of cotyledons can vary from two to 15 (rarely up to 24). Distribution: This family has a mostly temperate Northern Hemisphere distribution. It occurs in North America south to Nicaragua, the West Indies, throughout temperate (including North Africa) and

Picea likiangensis near Lijiang, Yunnan, China [31]

tropical Eurasia south to Sumatra and the Philippines. Pollination is by wind, causing allergies in some humans where Pinaceae are abundant. Seeds are dispersed by wind. Some species become aggressive invasives in parts of the world where they have been planted for timber. Phylogeny and evolution: The family is known from the fossil record since the Cretaceous. Originally the family included all conifers, but it is now restricted to the clade including the genus Pinus. There is good evidence to support the hypothesis that there has been a recent radiation of species in the three largest genera, Abies, Picea and Pinus. Some molecular studies have controversially indicated that the family is sister to the three families of gnetoids.

Pinus tabuliformis var. mukdensis, Royal Botanic Gardens, Kew, UK [31]

Abies forrestii, Royal Botanic Gardens, Edinburgh, Scotland, UK [31]

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PINALES Genera and species: Pinaceae include 11 genera with 224 species: Abies (49), Cathaya (1), Cedrus (4), Keteleeria (3), Larix (12), Nothotsuga (1), Picea (33), Pinus (c. 115), Pseudolarix (1), Pseudotsuga (7) and Tsuga (8). Uses: Most commercial softwood timber is from members of Pinaceae. They are also a major source of pulp for paper production and for tar and turpentine, essential oils etc. In Scandinavia, pine bark flour (Pinus sylvestris) is used in local cuisine, and young twigs of

GYMNOSPERMS

spruce (Picea abies) are used for tea or to flavour liquor. Many species of Pinus produce edible seeds. Commercially, pinenuts (piñones or pignolias; Pinus pinea) are harvested for this purpose. Several species of Picea and Abies are commercially grown as Christmas trees. In Mexico, some species of long-leaved pine are used for basketry. Lebanon cedar (Cedrus libani), now a rare species, was once abundant in the Levant and was harvested for its fragrant wood; the Temple of Solomon was built of this timber (Old Testament; Kings 5: 6). Larix has hard, heavy, decay-resistant

Larix decidua, young female cones, Royal Botanic Gardens, Kew, UK [31]

Cedrus libani forest in Lebanon [31]

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wood, which when knot-free (as ‘boatskin larch’) is in great demand for yacht building. Pines and other species are commonly used in dendrochronological studies to date buildings and ruins accurately. Pinaceae are planted as ornamentals throughout temperate and subtropical regions of the world, and cones of Pinaceae are often used in dried flower arrangements and painted for use as Christmas decorations. Etymology: Pinus is Latin for a pine tree.

Pseudotsuga menziesii, female cone with three-parted bracts, California, USA [31]

Pinus banksiana, male cones, Royal Botanic Gardens, Kew, UK [31]

ARAUCARIALES

GYMNOSPERMS

ARAUCARIALES Podocarpaceae fossils are known since the Early Triassic, c. 240 million years ago, whereas Araucariaceae fossils date back to the Mid Jurassic, c. 160 million years ago. The order consists of two families that are predominantly found in the Southern Hemisphere and are believed to be of Gondwanan origin.

Distribution: This mostly Southern Hemisphere family is found in southern South America, Southeast Asia, Malesia, the Philippines, New Caledonia, Australasia and some Pacific Islands.

Phylogeny and evolution: Originating in the Triassic, the family diversified and spread to both Hemispheres during the Jurassic and Early Cretaceous, becoming a significant component of Gondwanan forests until the late Cenozoic. Angiosperms dominated forests in the Cretaceous, which probably resulted in the extinction of some araucarian lineages, but some new genera also evolved. Continental separation and associated climatic drying and cooling reduced the ranges of these predominantly tropical trees, but volcanic activity provided new habitats in Australasia where Araucariaceae diversified. Now mostly restricted to some Southern Hemisphere areas, the family was formerly more widespread, Araucaria fossils being known from both Hemispheres from the Jurassic. Most extant Araucariaceae must have evolved from the Early Tertiary and dispersed to the islands of Australasia where they diversified; these islands provide exactly the tropical rainforest habitats where angiosperms were thought to have most successfully replaced conifers. This has more to do with the adaptability of the more recently evolved species of Agathis than their ability to compete effectively with angiosperms.

Araucaria angustifolia forest in Santa Catarina, Brazil [32]

Wollemia nobilis, male and female cones, Royal Botanic Gardens, Kew, UK [32]

32. ARAUCARIACEAE Kauri-tree family

These evergreen bisexual and unisexual trees have verticillate branches and spirally arranged leaves. Leaves usually have parallel venation. Male cones are cylindrical, and the sporophylls are numerous, each bearing about a dozen pollen sacs. Female cones are subglobose to ovoid and mature in two years. They disintegrate on the tree upon maturity, the cone scales one-seeded, without distinct bracts. Seeds have four cotyledons that are fused into two double cotyledons.

Genera and species: Extant Araucariaceae consists of three genera with 41 species: Agathis (21), Araucaria (19) and Wollemia (1). Uses: Many species are important timber trees because they are usually among the largest trees in the forest. Seeds of Araucaria angustifolia and A. bidwillii are locally consumed. Many species are common ornamentals, especially Araucaria heterophylla, the Norfolk Island pine, a common houseplant, and A. araucana, the monkey-puzzle tree, which got its name because when it was first introduced, it was said to be a puzzle how a monkey could climb such a prickly tree. The recently discovered Wollemi pine (Wollemia nobilis) is a peculiar conifer from Wollemi National Park, New South Wales, Australia, that has been saved from possible extinction by being brought into horticulture and distributed to gardens worldwide. The species thrives in mild temperate climates. Etymology: Araucaria is derived from Araucania, a region inhabited by the Mapuche (or Spanish: Araucana) people, now in Chile, where Araucaria araucana is native. Araucaria angustifolia, seeds, Curitiba, Brazil [32]

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Distribution: This family occurs in Neotropical mountains from Mexico and the Caribbean to Chile, and from tropical Africa, India, China and Japan to Australia, New Zealand and New Caledonia. The family is most diverse in Australasia.

Phylogeny and evolution: Podocarpaceae are most closely related to Araucariaceae, with which they form a clade. Both families are predominantly found in the Southern Hemisphere, but this may be more because they are prevalent in tropical and subtropical forests, which are currently mostly situated in the Southern Hemisphere continents. Fossils from the Northern Hemisphere are known. The family includes some peculiar members, such as the only parasitic gymnosperm, Parasitaxus usta, growing usually on the roots or branches of another Podocarpaceae, Falcatifolium taxoides, both endemic to New Caledonia. Even though Parasitaxus makes connections with the xylem of Falcatifolium by which it extracts water and nutrients, it gains carbon from fungi, so it is partly mycoheterotrophic, partly parasitic. Retrophyllum minus is unusual in its preference for an aquatic habitat, growing as an emergent small tree in streams also in New Caledonia. The genus Phyllocladus was, due to its unusual foliage morphology (phylloclades), presence of an aril-like structure and different pollination mechanism, segregated in a separate family, but apart from these differences it shares numerous characters with other Podocarpaceae (winged pollen, an epimatium etc.) and molecular studies show this genus to be closely related to other Podocarpaceae.

Prumnopitys andina, female and male cones, National Botanic Gardens, Glasnevin, Ireland [33]

Podocarpus nivalis, female cone, Royal Botanic Gardens, Edinburgh, Scotland, UK [33]

33. PODOCARPACEAE Yewpine family

These evergreen bisexual and unisexual shrubs and trees are usually terrestrial, rarely aquatic (Retrophyllum) or epiparasitic (Parasitaxus). Leaves are spirally arranged, sometimes opposite, and they are scale- or needle-like or flat and leaf-like, linear to lanceolate. Male cones are catkin-like with numerous crowded stamens, imbricate, each stamen with two pollen sacs. Female cones mature in one year and are reduced to a few fleshy bracts or scales (epimatia), borne on a thin peduncle containing a single ovule. Seeds are covered by a fleshy structure and have two cotyledons.

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Genera and species: Podocarpaceae consist of 19 genera with 185 species: Acmopyle (2), Afrocarpus (5), Dacrycarpus (9), Dacrydium (21), Falcatifolium (5), Halocarpus (3), Lagarostrobos (1), Lepidothamnus (3), Manoao (1), Microcachrys (1), Nageia (6), Parasitaxus (1), Pherosphaera (2), Phyllocladus (5), Podocarpus (104), Prumnopitys (9), Retrophyllum (5), Saxegothaea (1) and Sundacarpus (1). Uses: The family includes some minor timber trees, and many are threatened by overharvesting. Several species are used for cabinetry, furniture, and carving and turning because of their fine grain, soft wood and fragrance. An essential oil, methyl eugenol, from the wood of the longlived tree Lagarostrobos franklinii is now chemically synthesised and used as a wood preservative and an insecticide. Oil from seeds of Nageia nagi is edible and contains eicosatrienoic acid, a compound that can reduce swellings. Stems are used in floristry as everlastings. Etymology: Podocarpus is derived from Greek ποδός (podos), a foot, and καρπός (karpos), a fruit, referring to the obliquely stalked fruit that resembles a foot kicking a ball.

Retrophyllum minus, New Caledonia [33]

CUPRESSALES

GYMNOSPERMS

CUPRESSALES With an estimated age of some 245 million years, this is another old order that was formerly more diverse and widespread than it is at present. It consists of three families, Cupressaceae, Sciadopityaceae and Taxaceae.

34. SCIADOPITYACEAE Umbrella-pine family

These are evergreen bisexual trees with whorls of brown scales (which are the actual leaves) from which green needle-like cladodes (which are short stems) emerge. These cladodes resemble the needles of Pinaceae, but are composed of stem tissue and have two vascular bundles. Male cones are formed in dense terminal clusters. Female cones are subsessile, ovoid and disintegrate soon after

the seeds have been released. Scales are green, thin and flat, with five to nine seeds per scale. Seeds are flattened and ovoid with a narrow wing along each side. They are orange-brown and have two cotyledons. Distribution: This family is currently only found in southern Japan (southern Honshu, Kyushu, Shikoku) in mid-elevation cloud forests. It is listed as vulnerable, due to harvesting of the water-resistant wood for boat-making. Phylogeny and evolution: Sciadopityaceae are sister to Taxaceae and Cupressaceae. The family was widespread in the past and, before its discovery in Japan in the 19th century, it was only known from fossils from the Early Cretaceous 230 million years ago. It was more diverse in the past; Sciadopitys was, for instance, diverse in Tertiary Europe.

Sciadopitys verticillata, male cones, Royal Botanic Gardens, Kew, UK [34]

Genera and species: Sciadopityaceae consist of the single genus Sciadopitys that has only one extant species, S. verticillata. Uses: The koyamaki or Japanese umbrella pine is a popular garden plant throughout the temperate zones, despite its relatively slow growth. It is remarkably hardy and grows well even in cold climates. The wood is sometimes used for timber, but not on a commercial scale. Baltic amber is composed of the resin of extinct Sciadopityaceae. Amber has been appreciated for its colour and is often used for jewelry, but amber is also used in perfumes and folk medicine. Etymology: Sciadopitys is derived from the Greek σκιαδος (skiados), a whorl, and πίτυς (pitys), a fir tree.

Sciadopitys verticillata, female cone, Royal Botanic Gardens, Kew, UK [34]

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35. CUPRESSACEAE Cypress family

These are bisexual and unisexual, resinous and aromatic terrestrial trees and shrubs, without or with knee-like roots in aquatic Taxodium. Lateral branches are similar to leading shoots and are densely clothed by scale-like leaves or by leaf bases. Leaves are simple, persistent or deciduous, alternate and spirally arranged (sometimes twisted and appearing two-ranked), opposite in four ranks, or whorled, deltate to linear, sessile or petiolate; twigs are often heterophyllous. Male cones are axillary or terminal, solitary or in clusters of two to five (to 20), sometimes in panicles. They are spherical to oblong, and the sporophylls overlap, bearing two to ten pollen sacs. Female cones are compound, axillary, terminal, solitary or in clusters of two to five (to c. 100); the scales are usually overlapping and fused to subtending bracts, but sometimes with only the bract apex free, the fused scale/ bract complex peltate, oblong or cuneate, woody or fleshy at maturity, bearing one to 20 ovules. Seeds are wingless or with two or three wings, and the number of cotyledons varies from two to five, occasionally up to nine. Distribution: This family is nearly cosmopolitan. It is found on all continents except Antarctica. The generic diversity is greatest in the Southern Hemisphere and shows a relictual distribution, except for the largest genus Juniperus, which is widespread across the Northern Hemisphere, extending from the Arctic to the subtropics. Phylogeny and evolution: Fossils of Cupressaceae have been known since the Jurassic. The family was formerly divided into two

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families: Cupressaceae sensu stricto, with whorled or opposite (four-ranked) leaves, and Taxodiaceae, with mostly alternate leaves. The two former families are united in having female cones with fused bract/scale complexes. The leaf orientation has proven not to be an important character to distinguish between families and molecular studies have confirmed a close relationship between these groups, which is why they are now united. The clade of Cupressus s.l. has been contested in the past, but the group appears to be best treated as five genera, the Vietnamese golden cypress Xanthocyparis and the Nootka cypress Callitropsis forming a grade leading up to the New World Hesperocyparis, the Old World Cupressus and panboreal Juniperus. In principle these can all be merged into a single genus, but this will result in the loss of the well-established and large genus Juniperus, destabilising the taxonomy of this economically important group. Callitropsis nootkatensis, a commonly cultivated species has, however, been taxonomically unstable, being formerly placed in Cupressus, Chamaecyparis and Xanthocyparis. Actinostrobus and Neocallitropsis have been merged with Callitris. Genera and species: Cupressaceae consist of 30 genera with c. 146 species: Arthrotaxis (3), Austrocedrus (1), Callitris (22), Callitropsis (1), Calocedrus (4), Chamaecyparis (5), Cryptomeria (1), Cunninghamia (2), Cupressus (9), Diselma (1), Fitzroya (1), Fokienia (1), Glyptostrobus (1), Hesperocyparis (16), Juniperus (c. 50), Libocedrus (5), Metasequoia (1), Microbiota (1), Papuacedrus (1), Pilgerodendron (1), Platycladus (1), Sequoia (1), Sequoiadendron (1), Taiwania (2), Taxodium (2), Tetraclinis (1), Thuja (5), Thujopsis (1), Widdringtonia (4) and Xanthocyparis (1). Uses: Cupressaceae include the largest (Sequoiadendron giganteum) and tallest (Sequoia sempervirens) trees in the world. Both species (and numerous other members of the family) are commonly harvested for timber. Wood of many species is resistant to fungal decay and termite damage and is therefore often used in construction.

Chamaecyparis and Cunninghamia are in demand in Japan and China, respectively, for coffin wood. Wood of many species is aromatic and therefore often called ‘cedar wood’, and is then usually confused with the wood of Cedrus (Pinaceae) or Cedrela (Meliaceae), which are all aromatic timbers. Fleshy cones (‘berries’) of juniper (Juniperus communis) are commonly used to flavour English gin, Dutch jenever and German sauerkraut. Many species are popular in horticulture as architectural elements in the garden. Because of the association with grieving, Cupressaceae have been planted in graveyards in various cultures in Europe (Juniperus), the Middle East (Cupressus) and East Asia (Platycladus, Thuja). The columnar Cupressus sempervirens or arborvitae (the ‘tree of life’) has been a traditional plant in graveyards since ancient times throughout the Mediterranean, and since Roman times it has been grown in gardens, providing a picturesque ‘Italianate’ feature. Taxodium grows in swamps and is remarkable in forming knee roots (the function of which is unknown). Etymology: Cupressus is the Latin name for a cypress tree, from Greek, κυπάρισσος (kuparissos), probably derived from an unknown Mediterranean language. This was a tree sacred to the god Pluto, who changed his grieving boy companion Cyparissos into a cypress tree, hence its abundance in Mediterranean graveyards. Juniperus communis, female cones, Finland [35]

CUPRESSALES

GYMNOSPERMS

Callitris columellaris, female cone, Western Australia [35]

Cryptomeria japonica, female cones, Royal Botanic Gardens, Kew, UK [35]

Cupressus sempervirens, male and female cones, France [35]

Papuacedrus papuana var. arafakensis, Glasgow Botanic Gardens, Scotland, UK [35]

Taxodium distichum, Twickel Estate Gardens, the Netherlands [35]

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36. TAXACEAE Yew family

GYMNOSPERMS

bear a single seed, and the hard seed coat is partially or wholly covered with a fleshy or leathery aril, resembling a berry. Seeds have two cotyledons. Distribution: This family occurs in North and Central America, North Africa and throughout Eurasia to Malesia and New Caledonia.

These are bisexual and unisexual evergreen trees and shrubs, usually not resinous or aromatic. Lateral branches are similar to leading shoots. Leaves persist for several years, are shed singly, are arranged alternately and spirally but are often twisted so as to appear two-ranked, rarely opposite. Leaves are simple, needle-like and linear to linearlanceolate. Male cones are solitary or clustered, axillary. They are globose to ovoid, with the sporophylls bearing two to 16 pollen sacs. Female cones are axillary and are reduced to one or two ovules subtended by bracts. Cones

Phylogeny and evolution: Genetic relationships among Taxaceae have proven difficult to assess, but it seems that Amentotaxus is part of core Taxaceae, whereas Cephalotaxus is sister to the rest, although with weak support. Tertiary fossils of Amentotaxus differ little from extant species, making these ‘living fossils’. Members of Taxaceae are characterised by slow rates of evolutionary change. The family is sometimes divided into two or more subfamilies. Genera and species: Taxaceae include six genera with 32 species: Amentotaxus (6), Austrotaxus (1), Cephalotaxus (11), Pseudotaxus (1), Taxus (7) and Torreya (6).

Uses: The wood of some species of Taxaceae is used for carving. The fleshy aril of Taxus is edible, but it has to be consumed with caution because the seeds of all species of Taxus are poisonous, containing the alkaloid taxol; this compound inhibits mitosis and is used in synthesised form (paclitaxel) in chemotherapy treatment for various types of cancer. Clippings from yew hedges are collected from gardens around Western Europe to harvest this compound. Like cypress in the Mediterranean, yew is evergreen and often planted in churchyards and ancient burial grounds in Britain, Ireland and Normandy (perhaps as a remnant of druidic tradition). Yew is also the preferred wood for making longbows due to its flexibility. It was also a prized wood to use for making musical instruments, especially lutes. Seeds of the Japanese kaya, Torreya nucifera, are edible and pressed to produce cooking oil. The yellow wood of kaya is used for go boards, a game played in East Asia. Etymology: Taxus is Latin for a yew tree.

Cephalotaxus harringtonia subsp. drupacea, female cone, National Botanic Gardens, Glasnevin, Ireland [36]

Ancient yew, Taxus baccata, in the churchyard of Downe Village, Kent, UK [36]

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Taxus baccata, male cones, Box Hill, England, UK [36]

Taxus baccata, female cones, Royal Botanic Gardens, Kew, UK [36]

ANGIOSPERMS Imagine a world without flowers – it was for the great majority of its existence. Some 245–160 million years ago a group of plants emerged that had their reproductive leaves organised in whorls with sterile leaves enclosing them and large female organs covered in tissue to protect the developing seed. The precise way flowers developed and from what pre-existing group of gymnosperms (seed plants without flowers) flowering plants evolved is still a mystery. Evolutionary developmental biologists have identified the genes that control floral development in angiosperms and their counterparts in gymnosperms, but they have not unravelled the way in which these genes changed and first started being able to produce flowers. We thus know the “before and after” but not the details of the route taken. Darwin referred to the origin and rapid rise to dominance of the angiosperms as an “abominable mystery”, but how the first flowers evolved is an equally great conundrum. Early f lowers co-evolved with the appearance of a greater diversity of insect groups, particularly beetles, which fed on the f lowers, pollen and seeds, but also pollinated these organs. From herbivory, plants and insects co-evolved, and flowers came to host their pollinators, providing food rewards while not being greatly harmed. Flowers with lots of stamens evolved, dusting the visitors while they ate fleshy petals with pollen then transported to a nearby flower. The developing seeds were located deep in tissues, f irst for their protection but later as fruits to attract animals to consume and disperse the seeds. One benefit of seeds is that plants became less dependent on permanent water. Seeds could survive in dormant stages when

conditions were unsuitable for growth, due to drought, fire or frost. Thus, seeds allowed early flowering plants to disperse more widely, and interactions of seeds and fruits with animals resulted in diversification of forms. This diversity of plants spurred greater diversity in animals, which evolved new ways of using plants for food and shelter. Flowering plants became so successful that they rapidly replaced other vegetation formed by earlier groups of seed plants. The first rainforests formed, modifying the climate more than the earlier gymnosperms ever managed, and these new habitats acted as a spur to further diversification. Angiospermdominated landscapes became the most diverse the planet has ever witnessed. With the evolution of large grazing mammals and grasses (Poaceae), grasslands evolved, where the growing stems of the plants are below ground, not exposed to grazing mouths and trampling hoofs. Annual life histories developed as another method of overcoming periods of the year when growing conditions were unsuitable (too wet or dry, hot or cold), and these plants put all their accumulated resources into the seeds that would produce their next generation. When finally a peculiar bipedal ape came on the scene, the diversity of flowering plants was enormous, and with its large brain and hands with opposable thumbs it made good use of the existing resources, especially the annuals, which were more easily domesticated and could form the basis of settled agriculture. Humans invented language, agriculture, art, science, religion and culture, all based on the diversity of f lowering plants and the resources they provide. Do we still need plants? If you see the big financial centres of

A selection of angiosperm seeds and fruits

glass and steel, you might wonder, but without plants there would be no food, medicine, paper, clothes, houses, fuel or clean air. Moreover, plants sustain people, making them happy and healthy. Flowers are important cultural symbols as well — a rose for England, a thistle for Scotland, an orchid for Singapore, a tulip for Holland and Turkey, a protea for South Africa and the sacred lotus for Buddhism. Give a rose to a loved one or a lily as a sign of sympathy when a loved one dies. A world without flowers would not be quite the same. Etymology: The word angiosperm is derived from the Greek αγγείων (angeion or aggeion), a vessel or capsule, and σπέρμα (sperma), a seed, in reference to the fact that the seeds of flowering plants are enclosed in a layered structure as opposed to those of gymnosperms (which are naked).

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THE ANA GRADE FAMILIES

AMBORELLALES

THE ANA GRADE FAMILIES (AMBORELLANAE, NYMPHAEANAE, AUSTROBAILEYANAE) We refer to these families as the ANA grade because they do not form a clade. These three superorders sucessively are sister to the three major clades of flowering plants: magnoliids, monocots and eudicots. They are composed of Amborellales, the sister of the remainder of the flowering plants; Nymphaeales, an order of water lilies and associated families that have a long fossil history; and Austrobaileyales, an order of vines, shrubs and trees with spirally arranged flower parts. Previously these were placed among the “dicots” (they do indeed have two seed leaves or cotyledons), but as previously treated by most taxonomists, the monocots are embedded among dicots, and thus we no longer refer to dicots as a meaningful evolutionary unit. The ANA grade is treated as series of separate entities apart from the magnoliids, monocots and eudicots.

AMBORELLANAE AMBORELLALES This order diverged c. 130 million years ago and is probably sister of the rest of the angiosperms. They are now only found on New Caledonia, which emerged from the ocean c. 37 million years ago. Amborella must have lived elsewhere for a long time before it dispersed to New Caledonia and became extinct in its original area of occurrence.

37. AMBORELLACEAE Amborella family

These dioecious irregularly branching, typically sprawling shrubs can sometimes appear vine- or tree-like and have simple, alternate, two-ranked leaves without stipules. Leaf margins are undulate and coarsely dentate. Venation is pinnate, the veins connecting near the margin. Inflorescences are axillary and cymose. Flowers are small, white, the perianth undifferentiated, spirally arranged, basally connate, with five to eight petals and several petaloid bracteoles. Male flowers have six to 25 sessile anthers. Female flowers have a few staminodes, superior ovaries and several (three–six) free carpels that develop into a cluster of stalked, fleshy red drupes. Seeds are pitted with pockets of resinous substances. 88

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Distribution: The sole species occurs in forests of New Caledonia at between 200 and 1,000 m on schistose soils and is locally common between the Dogny Plateau and the Tipindjé River basin. Phylogeny and evolution: Amborella was formerly included in Monimiaceae or, if recognised as a separate family, was often included in Laurales. DNA studies have since shown it to be sister to all other angiosperms. As a result, the family has now been placed in its own order Amborellales. Despite its isolated position outside the main angiosperm clade, this family should not be considered primitive and clearly exhibits some derived characters, including unisexual

Amborella trichopoda, male flowers, New Caledonia [37]

flowers. Pollination is by wind and insects. Amborellaceae lack developed wood vessels, but if this is to be interpreted as primitive or derived is not certain. There has been some controversy about its phylogenetic position, and some studies have instead placed it in a clade with Nymphaeales (including Hydatellaceae; see below), but the majority of studies support its position as stated above. Genera and species: Amborellaceae consist of the single species, Amborella trichopoda. Etymology: Amborella is the diminutive form of ambora, a native Malagasy plant name for Tambourissa (Monimiaceae), to which Amborella was originally thought to be related.

Amborella trichopoda, female flowers, New Caledonia [37]

NYMPHAEALES

THE ANA GRADE FAMILIES

NYMPHAEANAE NYMPHAEALES Families 38–40 form the order Nymphaeales, which are the waterlilies and relatives. They are all aquatic rhizomatous plants that have boat-shaped pollen and fused cotyledons. Fossils of Nymphaeales date back to the Cretaceous, and it has been suggested that the fossil Archaefructus, thought to be about 124 million years old, belongs to this order. Archaefructus is putatively one of the earliest known fossil flowering plants, although opinion about its position and relationships as well as its age have been subject to controversy.

38. HYDATELLACEAE Watertufts family

These minute, annual and sometimes perennial, usually (semi-)aquatic, clumpforming herbs have a short upright branching rhizome and narrow linear leaves with a single vein and no petiole. Leaves are glabrous and lack sheaths and ligules, distinguishing them from grasses that may grow nearby. Inflorescences are capitate, with a sessile scape and bracts, resembling a single

Trithuria submersa, inflorescence, Western Australia (KD) [38]

inverted flower with centrally placed stamens (male flowers) surrounded by ovaries (female flowers) or inflorescences unisexual. Flowers are minute and reduced, without a perianth, and unisexual. Male flowers have a single stamen with a long slender filament and an anther that is fixed at its base. Female flowers are a single stalked ovary with a single style, beaded stigmas and a superior ovary. The fruit is a capsule, indehiscent or splitting into three valves. Seeds are extremely small and difficult to see. Distribution: These peculiar diminutive plants are found in microherb communities in seasonally wet sites in Australia, New Zealand and India.

it has now been shown that Hydatellaceae are most closely related to the water lilies and hence are placed with Cabombaceae and Nymphaeaceae in Nymphaeales. The unusual floral characteristic of ovaries surrounding the stamens, otherwise found only in Lacandonia (Triuridaceae), is now thought to be due to these “flowers” actually being heads composed of stamens and pistil-like structures that each represent reduced individual flowers. The genus Hydatella, traditionally separated on the basis of its indehiscent fruits and unisexual plants, is now merged with Trithuria, the name that has nomenclatural priority. Genera and species: Hydatellaceae consist of the single genus Trithuria with c. 12 species that are difficult to distinguish.

Phylogeny and evolution: These plants were first believed to be grass-like monocots (originally placed in Centrolepidaceae), but

Etymology: Hydatella is a diminutive of the ύδωρ (hydor), water; e.g. a small water plant.

Trithuria filamentosa, Lake Dobson, Mt Field National Park, Tasmania, Australia (CD) [38]

Trithuria bibracteata, Perth, Western Australia [38]

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NYMPHAEALES

THE ANA GRADE FAMILIES

Cabomba aquatica, Singapore Botanic Gardens [39]

Brasenia schreberi, Warm Lake, Valley County, Idaho, USA (CD) [39]

39. CABOMBACEAE Fanwort family

These f loating aquatic perennial herbs have horizontal rhizomes or stems that are freely rooting at the nodes with two vascular bundles and long internodes. Submerged parts of the plants can be covered in a gelatinous sheath. Leaves are simple, petiolate, opposite or seemingly alternate, the floating leaves peltate with entire or lobed margins and dichotomously branching venation. Submerged leaves are palmately dissected, the parts dichotomously branching with linear segments (in Cabomba), or

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Cabomba caroliniana, Royal Botanic Gardens, Kew, UK [39]

entire (in Brasenia). Flowers are emergent from the water, solitary, small, hexamerous and actinomorphic. Sepals and petals are usually three, the petals with nectaries in Cabomba. Stamens are three or six (to 36), with slender filaments. Ovaries are superior, the carpels three to 18, with a capitate (in Cabomba) or elongate (in Brasenia) stigma. Fruits are aggregate and contain one, two or three seeds. Distribution: These are widely distributed in the Americas from Canada to Argentina and in Sub-Saharan Africa, temperate and tropical East Asia and eastern Australia. Cabomba is frequently introduced and naturalised outside its native range. Phylogeny and evolution: Fossils assignable to Cabombaceae are known from Lower Cretaceous (115 Mya) sediments in Brazil. Brasenia and Cabomba diverged from each other c. 20 million years ago. The family was formerly more widespread than at

present, based on fossil evidence of Brasenia schreberi from Europe. Cabombaceae share many characters with Nymphaeaceae, especially seed anatomy of Brasenia and Nymphaeaceae. Genera and species: Cabombaceae consist of two genera with six species: Brasenia (1) and Cabomba (5). Uses: Water shield, Brasenia schreberi, is cultivated in East Asia as a vegetable called junsai (Japanese) or chun cai (Chinese). Submerged parts of this species are covered with a mucilaginous jelly, which has potential to control algal and bacterial growth in ponds. Cabomba species are common oxygenating plants in the aquarium trade from which they may naturalise. Etymology: Cabomba is derived from an Amerindian name for the plant, which came into Latin through Spanish. Its origins have not been traced.

NYMPHAEALES

THE ANA GRADE FAMILIES

40. NYMPHAEACEAE Waterlily family

These are annual and perennial aquatic herbs with vertical stems or creeping rhizomes with complex vascular tissues. Tubers are often present. Leaves are simple, alternate, spirally arranged, peltate or cordate, submerged, floating or emergent. Flowers are solitary, usually emergent and replace a leaf in the spiral arrangement, and they are often large, usually with some distinction between outer (four to six) sepals and inner (0–70) petals, usually numerous in many spiral whorls, decreasing in size towards the centre, becoming staminodial. Stamens are numerous (up to 200), not all fertile and sometimes grading into petals, filaments stout, often flattened or petaloid. The ovary is superior, with many (three to 35) whorled carpels that are laterally or completely fused. The fruit is a spongy berry with many large seeds. Distribution: This is a globally distributed family, but absent from glaciated or dry Nymphaea lotus, private garden, Irvine, California, USA [40]

regions.They are absent from New Zealand, southern Australia and southern South America.

of complex origin. Some Barclaya and Nymphaea species are popular aquarium plants.

Phylogeny and evolution: The family is believed to have been much more diverse in the past. It is believed that they dominated aquatic habitats. The family has been suggested to be 121 million years old, but crown group diversification is believed to have occurred in the Northern Hemisphere during the Tertiary. Wind-pollinated, apetalous Ondinea purpurea from Western Australia is possibly embedded in Nymphaea and is now known as Nymphaea ondinea. Euryale and Victoria are closely related and could be considered part of the same genus, pending further evidence.

The biggest and the smallest: Discovery of the largest waterlily, the annual Victoria amazonica from South America, caused a sensation. It was named for Queen Victoria, and after it was first cultivated in 19th century Britain the leaf venation served as an inspiration for a then novel form of glasshouse architecture, most famously the Crystal Palace in London. With a diameter of 2.65 m (area 5.51 m 2) this is the largest undivided leaf on the planet. The smallest waterlily, Nymphaea thermarum, was discovered in 1987 in a hotspring in Rwanda but was thought to be extinct in its native habitat. It also gained widespread notice when it was revived from seeds at the Royal Botanic Gardens, Kew, from where it has now been reintroduced into the wild and distributed to other botanical gardens around the world. Theft of some of the plants on display at Kew also gained public notoriety.

Genera and species: Currently Nymphaeaceae consist of five genera with c. 85 species: Barclaya (4), Euryale (1), Nuphar (17), Nymphaea (c. 60) and Victoria (2). Uses: Nuphar polysperma seeds were used as a flour substitute by some native American tribes, and seeds of Euryale ferox are used as food in East Asia. Rhizomes and seeds of some Nymphaea species can also be eaten. Flowers of some Nymphaea species were used as a narcotic by shamans and priests to induce ecstasies. Nymphaea and Nuphar are commonly grown as pond plants, with many hybrids and cultivars Victoria cruziana, Helsinki Botanical Garden, Finland [40]

Etymology: Nymphaea is derived from Greek mythological creatures called νύμφη (nymphe), nymphs, who were divine female spirits often associated with natural features, most often with the life-giving flow of springs. Nuphar polysepala, Royal Botanic Gardens, Kew, UK [40]

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AUSTROBAILEYALES

THE ANA GRADE FAMILIES

AUSTROBAILEYANAE AUSTROBAILEYALES Families 41–43 represent the order Austrobaileyales. This order is difficult to characterise in morphological terms, but the three families share the presence of tiglic acid (a skin and eye irritant), a compound not unique to this order, but setting it apart from the magnoliid orders. They are woody lianas and trees and have bisexual flowers with undefined numbers of parts. The order has an estimated age of c. 150–200 million years.

41. AUSTROBAILEYACEAE Austrobaileya family

The single species is a liana with simple, opposite, leathery, oblong to narrowly ovate leaves that are glabrous and produce essential oils in spherical oil glands. Leaf margins are entire, and petioles are short, without stipules. Flowers are bisexual, axillary or terminal, solitary, pendulous, c. 5 cm across and exude a smell of rotting fish to attract flies for pollination. There are 11–24 tepals

that are spirally arranged and spreading, the outer ones green and sepal-like, the inner ones cream with red or purple dots, variable in size and shape, but the innermost smallest. Flowers have six to 11 boat-shaped to flat, spotted stamens, with the anthers facing inward, embedded in the connective. There are nine to 16 flat, overlapping staminodes that surround the carpels. The ovary is superior, and carpels are eight to 13 and free with c. 6 mm long styles. The fruit is a stalked, ellipsoid, globose or pear-shaped berry that is 5–7 cm wide, fleshy in texture and orange-yellow in colour. The seeds are whitish and resemble a chestnut. Distribution: They are found in wet tropical rainforests between 380 and 1,100 m in northeastern Queensland (Australia). Phylogeny and evolution: The family is

Austrobaileya scandens, Queensland, Australia (CD) [41]

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suggested to have an age of c. 100–200 million years, depending on the analysis. There are no known fossils, but the pollen resembles that of fossil pollen Clavatipollenites from the Lower Cretaceous. Previously placed in Laurales as one of the most ‘primitive’ members, Austrobaileyaceae are instead the sister to the other families of Austrobaileyales (Schisandraceae and Trimeniaceae) in DNA-based analyses. Genera and species: Austrobaileyaceae include a single genus with one species: Austrobaileya scandens. Etymology: Austrobaileya is derived from Latin australis, southern, and two botanists called Bailey: British-Australian botanist Frederick Manson Bailey (1827–1915) and American wood anatomist Irving Widmer Bailey (1884–1967).

Austrobaileya scandens, habit, Royal Botanic Garden, Sydney, Australia [41]

AUSTROBAILEYALES

THE ANA GRADE FAMILIES

Trimenia neocaledonica, New Caledonia (JM) [42]

42. TRIMENIACEAE Bittervine family

Trimenia papuana, New Guinea (JM) [42]

round, fleshy berries. Seeds are hard, smooth or ridged.

43. SCHISANDRACEAE Star-anise family

Distribution: The family is restricted to eastern Malesia and northern Australasia from Sulawesi through New Guinea, the Solomon Islands, south to northern New South Wales (Australia) and from New Caledonia to Fiji in the Pacific.

These trees, shrubs and lianas have young shoots that are often hairy and accumulate aluminium in their tissues. Leaves are opposite, petiolate and without stipules. Leaf margins are entire or serrate, and the blade usually has translucent dots. Veins are pinnate and connected near the margin. Inf lorescences are axillary or terminal cymes or panicles. Flowers are unisexual or bisexual, small and wind-pollinated. Tepals soon fall off after opening of the flower, but they are spirally arranged, numerous (to 38), the outer ones swollen and somewhat peltate, the inner ones reduced and more membranaceous. Flowers have seven to 25 spirally arranged stamens with short filaments and a connective protruding apically. The ovary is superior, the carpel solitary (rarely two), but rudimentary in male flowers, the stigma sessile and tufted. Fruits are small,

Phylogeny and evolution: Trimenia was originally thought to belong to Cunoniaceae, and when segregated from that family it was first placed in Ternstroemiaceae (a family now included in Pentaphylacaceae). It was associated with Monimiaceae until 1950, when Trimenia was placed in its own family in Laurales. It has now been shown to form an isolated lineage in Austrobaileyales. A second genus, Piptocalyx, is now merged with Trimenia. Fossil seeds were found in 118 million year old deposits in Hokkaido, Japan. Genera and species: Trimeniaceae consist of the single genus, Trimenia, with eight species. Etymology: Trimenia is named for British botanist Henry Trimen (1843–1896), who was director of the Royal Botanical Garden Peradeniya (Sri Lanka, then Ceylon). The genus does not, however, occur in Sri Lanka.

These are small trees, shrubs and twining lianas, with some (Illicium) accumulating aluminium. Leaves are aromatic, alternate, spirally arranged, often in false whorls or clusters at the ends of branches, simple and glabrous. Leaf margins are entire, sinuate or denticulate, petiolate and without stipules. Flowers are solitary, paired or a few clustered in the leaf axils. Flowers are bisexual (Illicium) or unisexual, with five to 30 undifferentiated tepals in one to several whorls, the outer ones small and bract-like, the middle ones larger and more colourful, the inner ones often reduced and sometimes transitional to stamens. Stamens are four to 50 or more numerous, free to completely fused, the anthers basifixed with the connective linear and protruding at the tip, often swollen and broader. The ovary is superior with five to 100 or up to 300 carpels arranged in a single Plants of the World

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AUSTROBAILEYALES whorl (Illicium) or spirally arranged, free, but laterally compressed and attached at the base of the flower or forming a subglobose mass. Styles are short, slender or conical. The fruit is an aggregate of explosive follicles (Illicium) or fleshy berries (Kadsura, Schisandra). Seeds have a hard seed coat and a circular cap. Distribution: The family is disjunctly distributed from the southeastern USA and Mexico into the Antilles and in East Asia from the Russian Far East and Japan to Sri Lanka, Java and Sulawesi.

THE ANA GRADE FAMILIES

included in a broad Magnoliaceae, but were later segregated into two families (Illiciaceae and Schisandraceae), still in the order Magnoliales. With increasing knowledge of morphology and anatomy, the two families were then placed together in the order Illiciales. DNA analyses placed these families together in Austrobaileyales, in which they are treated as a single family. Illicium separated from the other two genera some 75–90 million years ago. Genera and species: Schisandraceae consist of three genera with 85 species: Illicium (44), Kadsura (16) and Schisandra (25).

Phylogeny and evolution: The family had a continuous distribution in the Northern Hemisphere in the Tertiary, but died out in Europe and western Asia during the ice ages. Members of this family were previously

Uses: Fruits of some Schisandra species are edible and can be made into jams and juices. The sour fruits of Kadsura scandens

Etymology: Schisandra is derived from the Greek σκίζει (skizei), to split, and άνδρες (andres), men, in reference to the wellseparated anther cells.

Illicium henryi, Caerhays Estate, England, UK [43]

Illicium anisatum, National Botanic Gardens, Glasnevin, Ireland [43]

Kadsura longipedunculata, female, Helsinki Botanical Garden, Finland [43]

Schisandra rubriflora, male flowers, Royal Botanic Gardens, Kew, UK [43]

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are consumed in Malesia. Unripe fruits of Illicium verum are harvested as star anise, a culinary spice, also used in teas, liqueurs and medicine (as an antiviral). Illicium was used in ancient China as an insecticidal fumigant. Oil from Illicium anisatum from Japan and Korea is used for perfume, but it is toxic and locally used as a fish poison. Fruits of this species are common in ornamental flower arrangements and potpourri mixes. They are toxic and easily confused with true star anise. Some species of Illicium, Kadsura and Schisandra are cultivated as ornamentals.

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Illicium simonsii, fruits, Royal Botanic Gardens, Kew, UK [43]

CANELLALES

MAGNOLIIDS CANELLALES Families 44 and 45 are placed in Canellales, an order that can be recognised by the chemical composition of the leaves. The bark of several species of this order were used for various purposes but most notably as a cure for scurvy. An age of 122–125 My is estimated for this order.

44. CANELLACEAE Canela-bark family

tube. The ovary is superior, unilocular with two to six carpels and a short fat style that bears a two- to six-lobed stigma. The fruit is a berry.

Genera and species: Canellaceae consist of six genera with 18–21 species: Canella (1), Capsicodendron (2), Cinnamodendron (8), Cinnamosma (3), Pleodendron (3) and Warburgia (1–4).

Distribution: The family is disjunctly distributed in the New World (Florida, Central America, West Indies and the Atlantic Forest in Brazil) and in the Old World (only eastern Africa and Madagascar).

Uses: Bark of Canella winterana is used as a condiment and stimulant, for flavouring tobacco, as a fish poison and for timber (as Bahama whitewood) in the Caribbean. The bark of Cinnamodendron corticosum is used as a spice in the West Indies. Leaves of Warburgia ugandensis are eaten in curries in East Africa, and its resin is used to preserve wood. Fragrant wood of the Madagascan endemic Cinnamosma fragrans is used for ceremonial purposes in India, threatening natural stands of this species.

These trees, sometimes shrubs, have aromatic, alternate, simple, entire, petiolate leaves without stipules. They are commonly dotted with glands. Inf lorescences are axillary or terminal panicles or racemes, but flowers are sometimes solitary. Flowers are bisexual and regular, with three thick, leathery sepals and five to 12 petals. Petals are in one or two whorls, or spirally arranged, usually free, fused in Cinnamosma. Six to 12 stamens are connate into a tube, and the anthers are fixed to the outside of this filament

Phylogeny and evolution: The structure of the seed coat resembles that in Winteraceae and Illicium, and the family was thus long thought to be related to these. However, their parietal placentation confused early botanists, and these anatomical characters putatively shared with Myristicaceae also complicated placement. Their chemical properties (drimane-type sesquiterpenoids) are similar to those in some Winteraceae, and this relationship has been corroborated by molecular analyses. The two families are now placed in the separate order Canellales.

Warburgia ugandensis, National Museums of Kenya, Nairobi [44]

Cinnamosma fragrans, Orangea Forest Reserve, Antsiranana, Madagascar (CD) [44]

Etymology: Canella is a diminutive form of the Greek κάννα (kanna), a reed or cane, originally of Irish Celtic origin. The Spanish name ‘canelo’ is often used for plants in Canellaceae and Winteraceae that produce Winter’s bark. Canella winterana in fruit, Pointe-aux-Châteaux, Guadeloupe [44]

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CANELLALES

Tasmannia insipida, Australian National Botanic Gardens, Canberra [45]

MAGNOLIIDS

Tasmannia lanceolata, private garden, Kingston upon Thames, Surrey, UK [45]

45. WINTERACEAE Winter’s bark family

These aromatic shrubs, trees and rarely lianas are usually terrestrial, but sometimes epiphytic. Leaves are simple, spirally arranged and petiolate, lacking stipules, and they are usually dotted with glands and often whitish beneath. Inflorescences are terminal or axillary and compound in dichasia or the flowers solitary. Flowers are bisexual or unisexual (in Drimys), actinomorphic or bisymmetric. Sepals are fused into a cup-shaped calyx, rupturing when a f lower opens. Petals are two to many, free or the outer ones fused and rupturing as well. Three to many stamens are free, the filaments short and thick, and the anthers opening with lateral slits, the connective usually not developed. The ovary is superior, and one to many carpels are free or fused. Stigmas are sessile and circular,

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Pseudowintera colorata, private garden, Kingston upon Thames, Surrey, UK [45]

linear or cup-shaped. Fruit is a dry or fleshy berry, sometimes with stone cells. Distribution: This is a family with a widespread but patchy distribution in the montane tropics and temperate rainforests in the Southern Hemisphere, occurring from southern North America to northern South America (Mexico to Ecuador and Venezuela), eastern Brazil, coastal Chile, the Juan Fernandez Islands, Madagascar, the Philippines, Borneo, Sulawesi, New Guinea, the Solomon Islands, New Caledonia, eastern Australia, Tasmania and New Zealand. Phylogeny and evolution: Takhtajania perrieri from Madagascar (sometimes placed in its own family because of its parietal placentation) possibly diverged from other Winteraceae c. 45 million years ago, although morphological analysis has shown it is similar to Pseudowintera. The age of the family is suggested to be c. 125 million years old. Fossils assigned to Winteraceae have been found outside the current range of the family, suggesting it was more widespread in the past and that the current distribution is relictual. Drimys in the broad sense is paraphyletic, and hence Tasmannia needs to be applied to the Old World taxa. The genus Zygogynum is still in need of taxonomic revision but includes Belliolum and Bubbia.

Drimys winteri in fruit, private garden, Kingston upon Thames, Surrey, UK [45]

Genera and species: Winteraceae consist of five genera with c. 65 species: Drimys (6), Pseudowintera (3), Takhtajania (1), Tasmannia (5) and Zygogynum (c. 50). Uses: Tasmannia lanceolata was used as pepper substitute by colonial Australians and after introduction to England became established as ‘pepperleaf’ in Cornish cuisine. Dorrigo pepper (Tasmannia stipitata) is used for the same purpose in Australia. Winter’s bark (Drimys winteri) was used as an effective remedy for scurvy in the 17th and 18th centuries, until vitamin C could be synthesised. Etymology: This family is named for John Winter, captain of the ship Elizabeth that accompanied Sir Francis Drake’s journey around the world in 1577–1580. Winter sent a boat ashore to search for medicinal herbs after sailing around Cape Horn, and he discovered Drimys bark, which became a remedy for scurvy for centuries afterwards. Drimys winteri is called ‘canelo’ in Spanish, and it was often confused or substituted by Canella winterana from the Caribbean, which can be used for similar purposes. Δριμύς (Drimys) means tart or pungent in Greek, referring to the bitter taste of the bark.

CANELLALES

MAGNOLIIDS

Hero of Labour — Armen Leonovich Takhtajan (1910–2009) In 1940, Soviet-Armenian botanist Armen Takhtajan published his classification scheme for flowering plants, emphasising phylogenetic relationships between plants. It took a decade before his classification became known to scientists in the west, and he began collaborating with Arthur Cronquist, whose system was influenced by him. Takhtajan’s system, last updated in 2009, divided flowering plants into the classes Magnoliopsida (dicots) and Liliopsida (monocots), which he subdivided into subclasses. Similar in general to the Cronquist system, those of Takhtajan had greater complexity with smaller orders and families, to allow families to be easily morphologically defined. It sometimes blurred the distinction between family and genus. During Soviet times the teaching of classical genetics could lead to imprisonment, but Takhtajan openly fought this, calling the government ignorant, and his correspondence with the West must have made him something of a maverick among Soviet scientists. He was fired in 1948 from his two botanical jobs in Armenia, but was hired by the more independent Leningrad University a year later, where he ran a lab that explicitly defied the doctrines of Lysenko. He even fired Lysenkoists in his laboratory. He was director of the Komarov Institute of Botany from 1976 to 1986. An endemic Winteraceae from Madagascar, Takhtajania perrieri, was named in his honour, a species that was only found once in 1909 and was thought to be extinct until it was rediscovered in 1994.

Zygogynum pomiferum, Tchamba River Valley, New Caledonia (CD) [45]

Photo of Armen Takhtajan (public domain)

Drimys granadensis, San Francisco Botanical Garden, California, USA [45]

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PIPERALES

MAGNOLIIDS

PIPERALES Families 46–50 form the order Piperales, a clade of plants with sympodial growth and usually heart-shaped leaves with secondary palmate venation, often with oil glands. Anthers are usually in threes, and the perianth is either strongly reduced or the petals are fused. The group is estimated to have originated 110–175 million years ago.

46. SAURURACEAE Lizard’s-tail family

perianth. The three, four or six stamens are free or fused with the ovary. The three to five carpels bear distinct styles. Flowers produce no nectar, and the fruit is fleshy, indehiscent or dehiscent. Distribution: This family is found in North America and temperate East Asia (China, Indochina, Japan, Taiwan, Luzon, Java), often in swamps or other wet habitats.

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Members of this family are perennial, aromatic herbs with stoloniferous rhizomes. They have simple alternate leaves with stipules that are fused with the petiole. Inf lorescences are terminal spikes with bracts that subtend the flowers, the lowest bracts sometimes enlarged and petal-like (the entire inflorescence then resembling a single flower). Flowers are small and lack a

Phylogeny and evolution: Saururaceae are closely related to Piperaceae, with which they share many characters. The family has an estimated age of 75–78 million years. A fossil from the Eocene was attributed to the genus Saururus, but it differs in stamen number. Morphologically intermediate, Zippelia has been moved back and forth between the two families, but it is now firmly placed in Piperaceae on the basis of

Anemopsis californica, Royal Botanic Gardens, Kew, UK [46]

Gymnotheca chinensis, Cuc Phuong, Vietnam (CD) [46]

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molecular studies. Differences between the families are in stem vasculature and placement of ovules. Genera and species: Saururaceae consist of four genera with six species; Anemopsis (1), Gymnotheca (2), Houttuynia (1) and Saururus (2). Uses: Houttuynia cordata is often cultivated as a garden plant, but can become invasive. Shoots and rhizomes of this species are eaten as a vegetable in China and have a fish-like flavour. Saururus chinensis is used in Chinese medicine. Anemopsis californica, Saururus cernuus and S. chinensis make attractive plants for large aquaria or ponds. Etymology: Saururus is derived from the Greek σαύρα (saura), a lizard, and ουρά (oura), a tail.

Saururus cernuus, private garden, Kingston upon Thames, Surrey, UK [46]

PIPERALES

MAGNOLIIDS

Distribution: A pantropical family extending into the temperate regions in the Himalayas, Japan, South Africa and New Zealand, but mainly restricted to tropical forests.

47. PIPERACEAE Pepper family

Phylogeny and evolution: Piperaceae are the largest magnoliid family. Closely related to Saururaceae they are estimated to be 70–100 million years old. Diversification was initiated in the Lower Cretaceous, but much of the current diversity dates from the Tertiary and later. Herbaceous Verhuellia from the Greater Antilles, previously treated as a synonym of Peperomia, is sister to the remaining Piperaceae. Zippelia and Manekia are sister to a clade including both Peperomia and Piper. Piper is now generally treated in its broad sense, including Arctottonia, Macropiper, Lepianthes, Ottonia, Pothomorphe and Trianaeopiper. Sarcorhachis is a synonym of Manekia.

worldwide), from which the dried unripe fruit gives black pepper and white pepper when the peppercorn skin is first removed. Piper longum (long pepper) is also used as a spice and medicinally. Peppercorns were the main reason for trade between Europe and the East Indies in the 16th and 17th centuries and sparked the Chinese and European colonisation of the region. Piper aduncum and P. angustifolium are similarly used as minor spices in the Neotropics. Piper betle is the leaf chewed with lime and betel nuts (Areca, Arecaceae). Piper cubeba (cubebs), P. clusii (African cubebs) and P. guineense (Benin pepper) are used medicinally and to flavour tobacco. The roots of Piper methysticum (kawa pepper) are fermented in several Pacific countries to make a narcotic sedative drink. Kawa-kawa (Piper excelsum) is used as an aphrodisiac in New Zealand. Many species and cultivars of Peperomia are popular houseplants, especially P. argyreia, P. caperata and P. velutina.

These are herbs, shrubs, trees and lianas, sometimes epiphytic, with stems that have swollen nodes. Leaves are simple, entire, alternate or opposite, often aromatic, succulent or membranaceous, petiolate, the petiole in some genera sheathing the stem, sometimes having a ligule-like structure or with a cap-like prophyll (a leaf protecting the leaf bud). Blades are often oblique at the base, often cordate, sometimes peltate. Venation is variable, often palmate, sometimes pinnate. Inflorescences are axillary, opposite the leaves or terminal. Flowers are formed on a spike or raceme that can be singular or several together organised into umbels or racemes. Flowers are tiny and lack a perianth, but each is subtended by a bract. Two (to six) stamens are free. There are two to five carpels, the ovary is superior and the fruit is a berry.

Uses: Many Piper species are used as spices, most notably P. nigrum from India, Sri Lanka and Madagascar (now cultivated

Etymology: Piper is derived from the Sanskrit pippali, a berry or peppercorn, which came via Middle Indic pippari into Greek πιπέρι (piperi) and Latin piper, the name of the spice.

Piper nigrum, Brooklyn Botanical Garden, New York, USA [47]

Zippelia begoniifolia, fruits, Cuc Phuong, Vietnam (CD) [47]

Peperomia fraseri, Royal Botanic Gardens, Kew, UK [47]

Manekia incurva, Guadeloupe [47]

Genera and species: Piperaceae consist of five genera with c. 3,700 species: Manekia (4), Peperomia (c. 1,600), Piper (c. 2,100), Verhuellia (3) and Zippelia (1).

Peperomia emarginella, Serra de Maranguape, Ceará, Brazil [47]

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PIPERALES

48. ARISTOLOCHIACEAE Birthwort family

These are lianas, small trees, shrubs and rhizomatous perennial herbs with alternate, mostly entire, occasionally palmately lobed leaves that are usually cordate at their base, or they are achlorophyllous, leafless, root parasites, with rhizome-like stems that have haustorial roots connecting to the host plant (Hydnoroideae). Leaves have petioles and no true stipules, but stipule-like prophylls may be present and are fused and ochrea-like in Lactoris. Flowers are solitary, axillary and often grow from old wood. In Lactoris there are two to four male, female or bisexual flowers from short condensed shoots (brachyblasts), and in Hydnoroideae the solitary flowers develop underground, emerging only when they open. The perianth is formed in one (or two) whorls, actinomorphic and trimerous,

Hydnora africana, South Africa (DK) [48]

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MAGNOLIIDS

irregularly lobed, or zygomorphic and all parts fused into various pipe-shaped or other tubular structures. Stamens are five, six or numerous (>40) and arranged in one to four whorls. Filaments are free or fused or entire stamens are fused with the style forming a structure called a gynostemium. The anthers open by lengthwise slits, or pollen is extruded in threads (Hydnoroideae). The three to six carpels are fused (but nearly free in Lactoris), and the ovary is inferior, sometimes superior. The style is three- to six-lobed or variously branched, or sessile and flat in Hydnoroideae. The fruit is usually a dehiscent (basketlike) capsule but sometimes follicular or a dry berry, or in Hydnoroideae a leathery, circumscissile indehiscent berry with many seeds and a strong smell.

southern South America (Prosopanche) and in savannas and arid parts of the southern Arabian Peninsula, Sub-Saharan Africa and Madagascar (Hydnora).

Distribution: The family is widespread in the Americas (Canada to Argentina), throughout mainland Europe and North Africa, Sub-Saharan Africa, Madagascar, Sri Lanka, temperate and tropical East Asia to New Guinea and northern Australia. Lactoridoideae are restricted to the Juan Fernández Archipelago (Chile), where they grow on wet or foggy slopes usually in the forest understory at 400–600 m elevation. Parasitic Hydnoroideae are found in semi-arid regions of Costa Rica, Peru and

Phylogeny and evolution: Aristolochiaceae were previously thought to be allied to Annonaceae on the basis of some superficial floral characters (e.g. floral parts in threes), but this proved to be incorrect. Molecular studies have shown that Aristolochiaceae are sister to Piperaceae and Saururaceae, and they are therefore included in Piperales. Hydnoraceae and Lactoridaceae are included in Aristolochiaceae because they make the latter paraphyletic. Fossil pollen of Lactoris was found in the Cretaceous of southern Africa dated c. 69 million years old, but fossil pollen is also known from South America, India, Australia and Antarctica, which means that it was a widespread Gondwanan element that became extinct on the continents. The remaining wild population of Lactoris fernandeziana is restricted to Robinson Crusoe Island (Más a Tierra) and consists of c. 1,000 plants with low genetic diversity. Hydnoraceae were originally described as a group of fungi, even though the floral nature of the reproductive organs was recognised

Aristolochia anguicida, capsule, near Turbaco, Bolívar, Colombia [48]

Aristolochia pilosa, Ecuador [48]

PIPERALES

MAGNOLIIDS

Asarum speciosum, Royal Horticultural Society Garden, Wisley, UK [48]

Saruma henryi, Royal Botanic Gardens, Kew, UK [48]

Thottea siliquosa, Royal Botanic Gardens, Kew, UK [48]

Aristolochia arborea, New York Botanical Garden, USA [48]

Asarum caudatum, northern California, USA [48]

from the start. Because of their parasitic nature, an association with Rafflesiaceae was also assumed, but DNA studies have shown that Hydnoraceae are embedded in Aristolochiaceae. This association is morphologically supported by the inferior ovary and general fusion of flower parts. Aristolochia is here treated in its broad sense, including Einomeia, Endotheca, Euglypha, Holostylis, Howardia, Isotrema and Pararistolochia, and has an estimated age of 104–122 million years. The Asarum–Saruma clade is of more recent origin, c. 36–44 million years old. Genera and species: Aristolochiaceae consist of seven genera with c. 500 species in four subfamilies: Asaroideae – Asarum (c. 100) and Saruma (1); Hydnoroideae – Hydnora (c. 6) and Prosopanche (4); Lactoridoideae – Lactoris (1); Aristolochioideae – Aristolochia (c. 360) and Thottea (30).

to make a dessert, but the fruit is astringent on its own. Plants are high in tannins and have been used for tanning and preserving fish nets, and infusions have been used as a face wash to treat acne. Birthwort (Aristolochia clematitis) was used as an abortifacient in former times, and Virginian snakeroot (Aristolochia serpentaria) has snake-like roots that were thought to be effective in the treatment of snake bites. Neither of these is, however, fit for purpose due to their ineffectiveness and toxicity. Wild ginger, Asarum canadense, has been used as an inferior ginger substitute in North America. Aristolochia petersiana is used as an arrow poison in East Africa. Some species, such as pipevine or Dutchman’s pipe (Aristolochia durior), calico flower (A. littoralis) and pelican flower (A. gigantea, A. grandiflora, A. ringens), several asarabacca or wild ginger (Asarum) species and ‘upright wild ginger’ (Saruma henryi) are occasionally grown as garden ornamentals.

consisting of only a flower and root-like stems. Hydnoroideae are the only known angiosperms with no leaves or scales of any sort. Hydnora africana and H. triceps parasitise succulent Euphorbia species (Euphorbiaceae) and H. johannis only parasitises roots of Acacia and Albizia (Fabaceae). Prosopanche americana and P. bonacinae grow on the roots of Prosopis and other legumes (Fabaceae). Little is known about H. esculenta from Madagascar, which has unisexual flowers and has not been collected since 1947. Heat production (thermogenesis) occurs in the flowers of Prosopanche and in some Hydnora, attracting beetles and flies for pollination. Some species are easily overlooked, especially H. triceps, which produces subterranean flowers and fruits. Due to their inconspicuous nature and seasonal appearance, Hydnoroideae remain poorly known plants.

Uses: The fruits of jackal food, Hydnora africana, are deliciously sweet when baked on a fire. Fruit pulp can be mixed with cream

Parasitism: Hydnoroideae (Hydnora and Prosopanche) are achlorophyllous root parasites that are extremely reduced,

Etymology: Aristolochia is derived from the Greek άριστος (aristos), best, and λοχεία (locheia), childbirth, because some Mediterranean species were applied to cure infections after childbirth or to induce labour.

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MAGNOLIIDS

MAGNOLIALES Families 49 to 54 form the order Magnoliales. These woody plants can be recognised by their often two-ranked or spirally arranged leaves. Their petals are whorled (or spirally arranged), and their medium-sized seeds have an irregular ruminate endosperm (like nutmeg).

49. MYRISTICACEAE Nutmeg family

exposing woody seeds that are usually covered in a lacy or entire, leathery or fleshy aril. Distribution: This is a pantropical family that are often canopy trees in rainforests.

These aromatic, often dioecious trees, sometimes shrubs, have red sap and red, long terminal buds. Leaves are simple, alternate, often oriented in a plane, shortly petiolate and without stipules. Leaf margins are entire, and hairs on the leaf surfaces and stems are usually branched or stellate. Inflorescences are panicles or fascicled racemes. Flowers are small, actinomorphic and funnel-, bell- or urn-shaped. Tepals are usually three, basally fused and often fleshy. Male flowers have two to 40 stamens with fused filaments. Female flowers have a single carpel, superior ovary and bilobed stigma. The fruit is a fleshy to woody capsule, usually splitting in half, Myristica fragrans, Singapore (MC) [49]

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Phylogeny and evolution: Myristicaceae clearly belong to core Magnoliales, which probably evolved >100 million years ago. They are well supported as sister to Degeneriaceae. Fossils from upper Cretaceous deposits in the Sahara are known, and Eocene fossil seeds are known from Europe, e.g. from the London clay. Diversification of modern lineages happened fairly recently, c. 15–20 million years ago. Genera and species: Myristicaceae include 21 genera with c. 520 species: Bicuiba (1), Brochoneura (3), Cephalosphaera (1), Coelocaryon (4), Compsoneura (c. 19), Doyleanthus (1), Endocomia (4), Gymnacranthera (7), Haematodendron (1), Horsfieldia (c. 100), Iryanthera (20), Knema (c. 90), Mauloutchia (10), Myristica (c. 170), Osteophloeum (1), Otoba (8), Paramyristica (1), Pycnanthus (4), Scyphocephalium (4), Staudtia (1) and Virola (c. 65). Virola surinamensis, fruit, French Guiana [49]

Uses: Myristica fragrans is a tree with apricotlike fruits in which nutmeg (the seed) and mace (the aril) are formed. This native of the Banda Islands in the Maluku Archipelago (Moluccas) in Indonesia was important in the 17th century spice trade, giving the name “Spice Islands” to this region. Ground nutmeg is used as a culinary spice but with excessive use is addictive, toxic and potentially hallucinogenic. Nutmeg oil is used medicinally and for flavouring tobacco and toothpaste. Bark of Iryanthera, Virola elongata and Osteophloeum platyspermum is used locally as a hallocinogen. Gymnacranthera, Horsfieldia and Knema seeds have oils that are used to make candles. Fat from Otoba seeds is used to make soap, and Virola sebifera contains oils that are suitable for candle and soap making. Caihuba, Virola surinamensis, produces an edible oil that is similar to cocoa butter. Horsfieldia iryaghedhi, Pycnanthus angolensis, Staudtia stipitata and Virola koschnyi produce fine timbers. Etymology: Myristica is derived from the Greek μύρων (myron), a balm or ointment, probably derived from a Semitic root m’rr, meaning bitter, a cognate with myrrh. Compsoneura excelsa in fruit, Los Mogos, Osa, Puntarenas, Costa Rica (CD) [49]

MAGNOLIALES

MAGNOLIIDS

Tuliptree, Liriodendron tulipifera, Royal Botanic Gardens, Kew, UK [50]

Magnolia macrophylla, fruit, Nichols Arboretum, Ann Arbor, Michigan, USA [50]

Magnolia ×soulangeana (a hybrid of M. denudata and M. liliiflora), Royal Botanic Gardens, Kew, UK [50]

Magnolia stellata, private garden, Kingston upon Thames, Surrey, UK [50]

Magnolia doltsopa, Royal Botanic Gardens, Melbourne, Australia [50]

Magnolia campbellii, Royal Botanic Gardens, Kew, UK [50]

50. MAGNOLIACEAE

dissemination of scent and attracting pollinators. The fruit is cone-like with free or fused follicles. In many species the carpels dehisce, and the pendent seeds exhibit a red aril.

flowers, Pachylarnax with few carpels but many ovules per carpel, and Talauma with fused carpels. These genera have, however, been found to be embedded in Magnolia sensu lato, expanding that genus to > 250 species, a number that is still growing. The two species of Liriodendron are well-supported as sister to Magnolia. Magnoliaceae are probably sister to the rest of Magnoliales.

Tuliptree family

Distribution: The family has a disjunct distribution in eastern North America, tropical America (Mexico to Brazil and Peru), southern India, Sri Lanka, the Himalayas and throughout temperate and tropical East Asia (Japan and Korea to New Guinea). These trees and shrubs have simple, entire and lobed, spirally arranged and petiolate leaves and stipules that enclose the bud and sheath the stem; these soon fall off leaving a scar. Stalked flowers are formed singly on the end of branches or short axillary shoots. Petals are free, six or more, spirally or whorled, sometimes differentiated into sepal-like outer petals and petal-like inner ones. Numerous stamens are free and spirally arranged, the filaments short or elongate, often flattened, and the anthers are elongate with the connective produced into a tip. Ovaries are superior, often stalked. Carpels are usually numerous, sometimes few, spirally arranged and free. Beetles are the most frequent pollinators, and some species create heat in their flowers (thermogenesis), increasing the

Phylogeny and evolution: The 98 million year old fossil flower Archaeanthus and fossil fruits of Lesqueria have been assigned to Magnoliaceae. Liriodendron in particular was widespread across the Northern Hemisphere during the late Cretaceous and Tertiary. Numerous now extinct lineages have been recorded from fossils. More modern representatives appeared in the late Miocene in Eurasia, especially when compared to North American extant taxa, which are considerably older. Several modern genera were described on the basis of deviating morphological characters not found in Magnolia sensu stricto; these include Elmerillia with sessile ovaries, Kmeria with unisexual flowers, Manglieta with four or more ovules per carpel, Michelia with axillary

Genera and species: This is now a family consisting of just two genera with c. 267 species: Liriodendron (2) and Magnolia (c. 265). Uses: Essential oils from Magnolia champaca are used for perfumery; its leaves are used to feed silk worms. Timber of Magnolia is used for boxes, matches, engraving, flooring, broom handles, traditional Japanese shoes etc. Wood of Liriodendron (whitewood) is used for furniture, shingles, latches and formerly canoes. Many species are highly valued ornamentals. Etymology: Magnolia was named in honour of French botanist Pierre Magnol (1638–1715), who was the first to publish plant families in an intrinsic ‘natural’ classification. Plants of the World

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51. DEGENERIACEAE Masiratu family

MAGNOLIIDS

Distribution: This family occurs only in Fiji. Phylogeny and evolution: Degeneriaceae are closely related to Myristaceae. Wood anatomy is similar to Eupomatiaceae, but the two families appear not to have an exclusive relationship. Genera and species: The single genus Degeneria has two species: D. roseiflora and D. vitiensis, which due to the removal of the natural barrier between the two populations by human activity, are forming hybrid swarms.

These glabrous aromatic trees have simple, alternate, spirally arranged, entire, petiolate leaves without stipules. Flowers are formed solitarily on axillary peduncles and are large and actinomorphic. Three sepals are free. The 12–25 petals are free, in several whorls (or are nearly spirally arranged) and reduced in size toward the centre, merging into the numerous, spirally arranged flattened stamens. The ovary is surrounded by staminodia that are spoon-shaped and longer than the stamens. The ovary is superior, with a single carpel that is not fully closed when the flower opens. Stigmatic surfaces flare outwards. Flowers are pollinated by beetles; the staminodes spread and protect the stamens upon opening, the staminodes closing over the ovary the following day, exposing the stamens and protecting the ovary. The fruit has orange or red fleshy seeds that are embedded in fleshy tissue. The fruit dehisces after falling from the tree, and seeds are distributed by fruit pigeons and parrots that eat the fleshy pulp. Degeneria vitiensis, Monasavu Dam, Viti Levu, Fiji (CD) [51]

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Etymology: Degeneria was named for American botanist Otto Degener (1899–1988), who discovered it in Fiji in 1942.

52. HIMANTANDRACEAE Pigeonberry-ash family

actinomorphic but lack a perianth. The flower bud is instead protected by two closed bracts that form a cap over the flower. Strap-like staminodes and stamens are numerous, and the stamens are placed between staminodes; inner staminodes and some stamens bear glands. The superior ovary has seven to 28 free carpels that fuse in fruit. The fruit is a drupe with several flat hard seeds; it is dispersed by fruit pigeons. Distribution: The family is only known from Sulawesi, the Moluccas, New Guinea and northeastern Queensland (Australia), where it can be found in rainforests. Phylogeny and evolution: The family is probably most closely related to Eupomatiaceae/Annonaceae, but this relationship is not well supported. Genera and species: Himantandraceae consist of the single genus Galbulimima with two species: G. baccata and G. belgraveana, sometimes considered to be a single polymorphic species. Uses: The aromatic bark and leaves are boiled and used as a hallucinogen by Papuans. The trees are also used for timber.

These aromatic trees have simple, alternate leaves that are organised in a plane (tworanked). Leaves are petiolate, entire and without stipules. Lower leaf surfaces and young twigs are covered with copper-coloured peltate scale-like hairs. Solitary, axillary flowers are Degeneria vitiensis with fruit cut open to show seeds, Monasavu Dam, Viti Levu, Fiji (CD) [51]

Etymology: Himantandra is derived from Greek ιμάς (himas), a strap or thong, and άνδρες (andres), men, in reference to the strap-shaped stamens: It is a later synonym of Galbulimima. Galbulimima baccata, Queensland, Australia (CD) [52]

MAGNOLIALES

MAGNOLIIDS

53. EUPOMATIACEAE Bolwarra family

superior ovary has numerous, fused, spirally arranged carpels without styles. The fruit is a fleshy berry.

54. ANNONACEAE Soursop family

Distribution: The family occurs in the tropical rainforests of eastern New Guinea and the temperate rainforests of eastern Australia (Queensland, New South Wales, Victoria).

These are shrubs with root tubers that rarely become small trees. Leaves are aromatic, simple, alternate, two-ranked, entire and petiolate and lack stipules. Flowers are formed in an axillary position or terminally on shoots, sometimes caulif lorous, actinomorphic, without a perianth, but flower buds are protected by one or two fused bracts that form a cap over the bud. Numerous stamens have short, broad filaments, and basifixed anthers open with slits. The inner staminodes are numerous, up to 80, and bear glands. The petal-like staminodes open fully when in the female stage, but cover the ovary when in the male stage of the flower. Stamens and staminodes are basally fused, the entire structure falling off after the male phase of the flower. The stigmas are pollinated by Elleschodes beetles. The fallen staminal structures are eaten by the same beetles, which in doing so bring pollen from the ground back up to new flowers. The Eupomatia laurina, Royal Botanic Gardens, Kew, UK [53]

Phylogeny and evolution: Eupomatiaceae are morphologically most similar to Himantandraceae, which share characters of the f lower structure, but molecular results place Eupomatiaceae as the sister of Annonaceae, with which they share vegetative characters, pollen with a circular aperture and syncarpous berries. The family is estimated to have an age of c. 100 million years.

Etymology: Eupomatia is derived from the Greek ευ (eu), well, and πωματιών (pomation), a cap, referring to the cap that covers the flower bud.

Large trees, shrubs and lianas with fibrous bark and zigzag branches are typical for this family. Simple, alternate, usually two-ranked (in a plane) leaves are usually petiolate and lack stipules. Flowers are terminal or axillary, solitary or in fascicles, sometimes caulif lorous or (rarely) sprouting from underground runners. Flowers are usually bisexual with open development: the perianth enlarges when the flower has already opened. Sepals are usually three and free for most of their length, but they are often basally fused. Three to six (rarely 12) petals are usually placed in two whorls, but sometimes in a single whorl. The numerous stamens are usually spirally arranged, sometimes whorled, and staminodes are present in some genera. Filaments are usually short and free, sometimes elongate and fused into a tube. The superior ovary has one to many carpels that are free or partly to completely fused, and styles are also free or fused. The fruit

Eupomatia laurina, Royal Botanic Gardens, Kew, UK [53]

Annona muricata, fruit, Helsinki Botanical Garden, Finland (MC) [54]

Genera and species: Eupomatiaceae consist of the single genus Eupomatia, which has three species. Uses: The sweet bolwarra fruit of Eupomatia laurina has a strong, aromatic flavour and is used in cooking, jams, desserts and beverages.

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Cananga odorata, Singapore [54]

Anaxagorea javanica (WA) [54]

Uvaria curtisii (WA) [54]

is composed of one to several free, stalked berries, arranged in an umbel, or a fleshy fused berry. Seeds are hard and usually glossy.

Genera and species: Annonaceae include 111 genera in four subfamilies with c. 2,300 species: Anaxagoreoideae – Anaxagorea (30); Ambavioideae – Ambavia (2), Cananga (2), Cleistopholis (4), Cyathocalyx (7), Drepananthus (26), Lettowianthus (1), Meiocarpidium (1), Mezzettia (3) and Tetrameranthus (6); Annonoideae – Afroguatteria (2), Annona (162), Anonidium (4), Artabotrys (102), Asimina (7), Asteranthe (3), Bocagea (2), Boutiquea (1), Cardiopetalum (3), Cleistochlamys (1), Cymbopetalum (27), Dasymaschalon (25), Desmos (24), Diclinanona (3), Dielsiothamnus (1), Disepalum (9), Duckeanthus (1), Duguetia (93), Exellia (1), Fissistigma (48), Friesodielsia (51), Froesiodendron (3), Fusaea (2), Gilbertiella (1), Goniothalamus (136), Guatteria (210), Hexalobus (5), Hornschuchia (10), Isolona (20), Letestudoxa (3), Melodorum (10), Mischogyne (2), Mitrella (8), Mkilua (1), Monanthotaxis (56), Monocyclanthus (1), Monodora (16), Neostenanthera (4), Ophrypetalum (1), Porcelia (7), Pseudartabotrys (1), Pyramidanthe (1), Sanrafaelia (1), Schefferomitra (1), Sphaerocoryne (3), Toussaintia (4), Trigynaea (12), Uvaria (190), Uvariastrum (8), Uvariodendron (15), Uvariopsis (16) and Xylopia (157); Malmeoideae – Alphonsea (25), Annickia (8), Bocageopsis (4), Crematosperma (29), Dendrokingstonia (2), Desmopsis (14), Ephedranthus (6), Fenerivia (10), Fitzalania (2), Greenwayodendron (2), Haplostichanthus

(11), Huberantha (27), Klarobelia (12), Maasia (6), Malmea (6), Marsypopetalum (6), Meiogyne (16), Miliusa (52), Mitrephora (47), Monocarpia (1), Monoon (56), Mosannona (14), Mwasumbia (1), Neo-uvaria (5), Onychopetalum (2), Orophea (50), Oxandra (29), Phaeanthus (10), Phoenicanthus (2), Piptostigma (14), Platymitra (2), Polyalthia (120), Polyceratocarpus (8), Popowia (26), Pseudephedranthus (1), Pseudomalmea (4), Pseudoxandra (23), Pseuduvaria (58), Ruizodendron (1), Sageraea (9), Sapranthus (6), Sirdavidia (1), Stelechocarpus (3), Stenanona (14), Tridimeris (1), Trivalvaria (4), Unonopsis (48), Wangia (1) and Winitia (2).

Distribution: Annonaceae have a pantropical distribution, with a single temperate genus (Asimina) in the eastern USA. Phylogeny and evolution: Fossil Annonaceae are known from the Late Cretaceous. Annonaceae diverged from Eupomatiaceae c. 100 million years ago. Anaxagorea, often placed in a separate subfamily, diverged from the remaining Annonaceae c. 88 million years ago, after which the remaining Annonaceae diversified 70–85 million years ago, with the late Cretaceous fossil flower Futabanthus (c. 89 million years old) being one of the early members of modern Annonaceae. Recently some genus-level reorganisation was needed after DNA studies. The family is now divided into four subfamilies: Anaxagoreoideae, Ambavioideae, Annonoideae and Malmeoideae, the vast majority of genera belonging to the last two subfamilies. Rollinia is now included in Annona, and Haplostichanthus is now united with Polyalthia. Oxandra and Polyalthia were found to be polyphyletic, resulting in the recognition of the genera Hubera and Monoon, the latter including Enicosanthum.

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Christenhusz, Fay & Chase

Uses: Several species are cultivated for their fruits, especially Annona muricata (soursop, custard apple or guanábana), A. cherimola (cherimoya), A. squamosa (sweetsop or custard apple) and Asimina triloba (pawpaw or Michigan banana). Guanábana seeds have insecticidal properties. The fragrant flowers of ylang-ylang (Cananga odorata) are used in the perfume industry. A columnar form of Monoon longifolium (previously known as Polyalthia) is commonly planted as a street tree in the tropics. Etymology: Annona is derived from anona, the Taino (Amerindian) name for the fruit, not based on the Latin annus, year, as is sometimes claimed.

LAURALES

MAGNOLIIDS

LAURALES Families 55 to 61 comprise Laurales. These woody shrubs and trees are recognised by their opposite often aromatic leaves, flowers with a hypanthium and more or less spirally arranged perianth, concave receptacle and endotestal seeds. The age of divergence of this order has been estimated at 108–114 million years.

55. CALYCANTHACEAE Spicebush family

staminodes are situated on the inside edge of the flower base. The semi-inferior ovary holds one to many carpels that are fused if there is more than one. The fruit is a dry indehiscent capsule formed by the flower base and contains one to several glossy brown seeds. Distribution: Calycanthaceae are disjunctly distributed between North America, temperate East Asia and Australia (northern Queensland).

These are aromatic shrubs and trees with scaly buds. Leaves are simple, opposite, entire and petiolate with ethereal oil cells and no stipules. Flowers are solitary or in few-flowered clusters. The perianth consists of 15–40, spirally arranged tepals that are attached to the outside of the cup-shaped flower base (receptacle). Five to 30 stamens are inserted spirally on the rim of the flower base, and their filaments are short or the anthers sessile. The numerous

Phylogeny and evolution: Calycanthaceae are sister to all other Laurales and are believed to have diverged about 114–171 million years ago. Several fossils are thought to share characters with Calycanthaceae, but most are disputed because they also show characters not now known to occur in the family. Sinocalycanthus is morphologically intermediate between Calycanthus and Chimonanthus, but is now considered a synonym of the former genus,

Chimonanthus praecox, Royal Botanic Gardens, Kew, UK [55]

Calycanthus chinensis, Mt Tianmu, Anhui, China [55]

with which it forms hybrids in cultivation that are of ornamental value. Genera and species: Calycanthaceae include three genera with ten species: Calycanthus (3), Chimonanthus (6) and Idiospermum (1). Uses: Carolina allspice, Calycanthus floridus, was formerly used as a cinnamon substitute. Flowers of Chimonanthus praecox are used in East Asia to scent linen. Calycanthus oil is used in high-quality perfumes. Idiospermum australiense is an endangered rainforest tree from Queensland that was thought to be extinct but is now being cultivated in botanical gardens in Australia to ensure its survival. Calycanthus and Chimonanthus are frequently cultivated in gardens for their scented flowers. Etymology: Calycanthus is derived from Greek καλυξ (kalyx), crown or calyx, and άνθος (anthos), flower. Idiospermum australiense, Royal Botanic Gardens, Sydney, Australia [55]

Calycanthus floridus, North Carolina, USA [55]

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LAURALES

56. SIPARUNACEAE Fevertree family

MAGNOLIIDS

male flowers in search of a nesting site and in doing so transfer the pollen. Several drupes form together and are enclosed in a large false fruit that splits at maturity.

57. GOMORTEGACEAE Keule family

Distribution: This is a family from tropical America and tropical West Africa.

These are monoecious and dioecious shrubs, small trees and, sometimes, lianas. Leaves are simple, opposite and entire; the second leaf of a pair is represented by a midrib only in Glossocalyx, but is normally developed in Siparuna. Flowers are axillary and unisexual. Four to six tepals are fused, sepal-like or obscure (appearing to be absent). Male flowers have two to many stamens inside a ball-, cup- or urn-shaped flower base, which sometimes protrude from the valved sepals at anthesis. Female flowers have few to many, often sunken carpels, with the styles free at the tip and connate basally, usually protruding through the flower opening. Flowers are pollinated by gall midges, which lay their eggs inside male flowers, but visit both female and Siparuna guianensis, New York Botanical Garden, USA [56]

Siparuna nicaraguensis, Guatemala (MV) [56]

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Phylogeny and evolution: Previously Sipar unaceae were included in the polyphyletic Monimiaceae, which are now better understood, and the genera have been reorganised. Siparunaceae are sister to Gomortegaceae+Atherospermataceae. The oldest fossils of Siparunaceae are c. 88 million years old and have been recorded from deposits in the Late Cretaceous of Antarctica and the Eocene of Germany, so the family must have been widespread previously. Dioecy evolved several times from monoecy in Siparuna.

Etymology: Siparuna is derived from an Amerindian name (possibly Wayampi) for the plant in French Guiana.

These grey-barked, aromatic, evergreen trees have simple, opposite, entire, leathery, petiolate leaves without stipules. Inf lorescences are terminal or axillary racemes with a terminal flower. Peduncles are hairy and bear small bracts that drop off after opening of the flowers. Seven to ten spirally arranged tepals are hairy and intergrade with the seven to 13 stamens, the outer ones resembling petals, often with partly developed anthers; fully developed stamens have filaments with two stalked glands on each side. The one to three staminodes are sterile and often petal-like. The inferior ovary has two or three carpels, a short style and two or three stigmas. The fruit is a yellow, singleseeded drupe, similar to an avocado.

Glossocalyx brevipes, Monts de Cristal, Gabon (CD) [56]

Gomortega keule, Adelaide Botanic Garden, South Australia [57]

Genera and species: Siparunaceae consist of two genera and 78 species: Glossocalyx (4) in Africa and Siparuna (74) in the Neotropics.

Gomortega keule, Adelaide Botanic Garden, South Australia [57]

LAURALES

MAGNOLIIDS

Atherosperma moschatum, Australia (PW) [58]

Gomortega keule, habit, Adelaide Botanic Garden, South Australia [57]

Nemuaron vieillardii, Tchamba River Valley, New Caledonia (CD) [58]

Laurelia sempervirens, Royal Botanic Gardens, Kew, UK [58]

Distribution: Coastal central Chile (regions VII and VIII), where the single species grows in forests on the south-facing slopes of humid ravines. It is endangered due to overharvesting and clearing of forests for agriculture.

58. ATHEROSPERMATACEAE

Distribution: Atherospermataceae occur disjunctly around the southern Pacific: southern South America (Chile), New Guinea, eastern Australia, Tasmania, New Caledonia and New Zealand.

Southern-sassafras family

Phylogeny and evolution: Cretaceous fossils are known from the Antarctic Peninsula and taking their current distribution into account, the family may have a Gondwanan origin. The oldest fossils are 88 million years old. The family is sister to Gomortegaceae.

Phylogeny and evolution: Morphologically clearly part of Laurales, Gomortegaceae are sister to Atherospermataceae. Genera and species: Gomortegaceae consist of the single species, Gomortega keule. Uses: The sweet fruit of keule is edible and considered a delicacy in Chile, but it is rarely found outside that country. It is used to produce marmalade and liqueur. The easily worked wood was previously used to make high-quality furniture, but harvesting wood of this rare, slowly growing species is not sustainable. Etymology: Gomortega was named for Spanish botanist and physician Casimiro Gómez Ortega (1741–1818), first director of the Real Jardin Botánico de Madrid. Keule or queule is the Mapuche name for the plant.

These are aromatic trees and shrubs with T-shaped or simple hairs and simple, opposite, coarsely serrate leaves without stipules. Lateral veins of the leaves join to form a vein along the margin. Flowers are solitary and axillary or aggregated into cymose inflorescences. Flowers are bisexual or unisexual, more or less actinomorphic, with four to 20 tepals in two whorls; the perianth is poorly differentiated or clearly separable into sepals and petals. The 12 to numerous stamens and staminodes are fused, each with a pair of glands at the base. The superior or half-inferior ovary (the carpels then sunk in the flower base) have three to numerous free carpels with a lateral or gynobasic style. The fruit is an aggregate of indehiscent plumed achenes.

Genera and species: Atherospermataceae consist of seven similar genera and 20 species: Atherosperma (1), Daphnandra (9), Doryphora (2), Dryadodaphne (4), Laurelia (2), Laureliopsis (1) and Nemuaron (1). Uses: Laurelia sempervirens fruits are used as a spice in South America. The strongly scented bark of Atherosperma moschatum is made into an infusion for tea in Tasmania, and the fragrant wood of Doryphora sassafras is used in Australia to repel insects. Etymology: Atherosperma is derived from the Greek άθερ (ather), awn and σπέρμα (sperma), seed, referring to the plumed achenes.

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LAURALES

59. HERNANDIACEAE Lantern-tree family

These trees, shrubs and lianas are rich in essential oils. When they are lianas, they climb using petioles (Illigera) or specialised stem hooks (Sparattanthelium). Leaves are simple or palmately compound, entire or palmately lobed (Illigera), peltate or cordate at the base, palmately veined, petiolate, without stipules, sometimes with secretory cavities or cystoliths in the leaf blades.

MAGNOLIIDS

Flowers, formed in terminal cymes, are bisexual or unisexual and actinomorphic. Six to ten free tepals form two whorls and are similar in shape and size. Three to five stamens have filaments that usually bear a pair of glands at the base or sides. The inferior ovary has a single carpel with a terminal style and an apical stigma. Fruits are indehiscent dry samaras or enclosed in an inflated balloon formed from fused bracteoles, which are dispersed by sea currents, wind or animals. Distribution: The family has a pantropical distribution, often assocated with coastal habitats or rainforests. Phylogeny and evolution: Hernandiaceae are divided into two subfamilies that diverged c. 76 million years ago, one (Hernandioideae) morphologically more

Hernandia nymphaeifolia, fruit, Seychelles [59]

Gyrocarpus americanus in fruit, Cintalapa, Las Minas, Chiapas, Mexico (CD) [59]

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similar to Monimiaceae and the other (Gyrocarpoideae) morphologically similar to Lauraceae, but pollen morphology is shared by both subfamilies. In molecular studies, Hernandiaceae are sister to Monimiaceae, and this pair are sister to Lauraceae. Genera and species: Hernandiaceae include five genera and 58 species: Gyrocarpus (3), Hazomalania (1), Hernandia (23), Illigera (19) and Sparattanthelium (13). Uses: Gyrocarpus produces a light timber. Hernandia nymphaeifolia is sometimes used as a street tree in cities in the tropics. Etymology: Hernandia was named for Spanish naturalist and court physician Francisco Hernández de Toledo (1514–1587), who took part in the first scientific mission to the Americas.

Hernandia nymphaeifolia, Seychelles [59]

Sparattanthelium botocudorum, Recife, Brazil [59]

LAURALES

MAGNOLIIDS

60. MONIMIACEAE Boldo family

These hermaphroditic, monoecious and dioecious, aromatic trees, shrubs and lianas have simple, opposite, entire or serrate, gland-dotted, pinnately veined, petiolate leaves without stipules. Bisexual or unisexual flowers are solitary or produced in cymes or racemes; they are actinomorphic or somewhat oblique. The flower base (receptacle) is hollow, the perianth has distinct tepals in two whorls or the perianth is entirely absent. The outer tepal whorl (when present) has four parts that are sepal-like and sometimes fused and cap-like, the inner whorl (when present) has seven to 20 (or more) free petal-like parts. Ten to numerous free stamens form one or two whorls, and these surround one to 50

staminodes. Filaments do not bear glands. The superior to partly inferior ovary has (one to) three to many free carpels, with sessile, apical stigmas. Flowers are pollinated by small insects such as thrips that lay their eggs in the fig-like flowers or are visited by other insects when the flowers are of a more conventional structure. The fruit has indehiscent achenes aggregated in heads fusing to produce a false fruit formed by the fleshy flower base that splits irregularly when ripe. Distribution: This pantropical family extends into the temperate zones in southern South America (Chile), eastern Australia, Tasmania and New Zealand. Phylogeny and evolution: The family used to include Atherospermataceae and Siparunaceae, which are morphologically similar but make the family polyphyletic with regard to Hernandiaceae and Gomortegaceae. Monimiaceae are sister to Hernandiaceae and are estimated to have an age of c. 90 million years. Fossil wood dated at 85 million years has been used to calibrate phylogenetic trees of this clade. The family is thought to be of eastern Gondwanan origin, but the current

Tambourissa purpurea, Royal Botanic Gardens, Kew, UK [60]

distribution has been achieved by several long-distance dispersal events. Genera and species: Monimiaceae include 24 genera and c. 275 species: Austromatthaea (1), Decarydendron (3), Ephippiandra (6), Hedycarya (11), Hennecartia (3), Hortonia (3), Kairoa (2), Kibara (45), Kibaropsis (1), Lauterbachia (1), Levieria (7), Macropeplus (1), Macrotorus (1), Matthaea (6), Mollinedia (90), Monimia (3), Palmeria (15), Parakibara (1), Peumus (1), Steganthera (c. 17), Tambourissa (45), Tetrasynandra (3), Wilkiea (6) and Xymalos (1). Uses: The leaves of boldo, Peumus boldus, can be made into a digestive hot drink, its fruits are also edible and its bark is used as a dye in Chile. Hedycarya angustifolia is sometimes used for furniture making in Australia. Boldo and lemonwood (Xymalos monospora) produce good timbers. Etymology: Monimia is derived from Μόνιμη (Monime), the wife of King Mithridates VI of ancient Pontus (died 63 BC). In modern Greek the word is used to mean ‘permanent’.

Peumus boldus, Adelaide Botanic Garden, South Australia [60]

Hedycarya angustifolia, Australian National Botanic Gardens, Canberra [60]

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LAURALES

61. LAURACEAE Bay-laurel family

This family consists of aromatic trees and shrubs, except Cassytha, which are parasitic twiners with scale-like leaves and stem suckers (haustoria). In all genera other than Cassytha, leaves are simple, alternate, opposite or whorled, entire or lobed, petiolate and without stipules. Inflorescences are mostly axillary panicles or false umbels, rarely a head or flowers solitary. Flowers are actinomorphic, bisexual or unisexual, trimerous. The small, flat to enlarged and urn-shaped flower base is free from the ovary. Tepals are formed in two equal whorls, usually undifferentiated. The many stamens are usually in four whorls, the innermost consisting of sterile staminodia or this whorl absent, usually one whorl bearing glands at the base of the filaments. The ovary is usually superior, rarely inferior (Hypodaphnis) and has a single carpel. The fruit is a one-seeded berry or drupe, usually with the flower base and flower stalk enlarged to form a leathery or woody cup surrounding the base of the fruit, rarely completely enclosing it. Distribution: This widespread temperate and tropical family occurs in the Americas (eastern Canada and California to Argentina and southern Chile), Macaronesia, the Mediterranean, Sub-Saharan Africa, Madagascar, the Mascarenes, Asia (India to Korea and Japan), Australia (including Tasmania), New Zealand and many Pacific islands east to Hawaii. Phylogeny and evolution: Lauraceae were a dominant family in Middle Cretaceous floras, and many Triassic fossils from North America can be assigned to modern genera, especially Sassafras, which has a remarkably

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variable leaf shape. Fossilised Sassafras-like wood has, however, been found in Antarctica, implying a broader distribution of this genus. The oldest fossils are c. 100 million years old. Despite the generally large seeds of this family, most clades in recent phylogenetic analyses include species from different continents, implying frequent long-distance dispersal across oceans. The Macaronesian species, for instance, are closely related to American species, but not to each other, implying two independent dispersal events from the Americas to the Canary Islands, where the family is emblematic due to the ancient ‘laurisilva’ forests, believed to be similar to European forests before the ice ages. Hypodaphnis, with its inferior ovary, is sister to the rest of the family, followed by parasitic Cassytha on a long branch, although some analyses also show Cassytha to be sister to a clade comprised of Caryodaphnopsis and Neocinnamomum; all analyses place the parasitic Cassytha firmly in Lauraceae. The species-rich genus Ocotea diversified recently. Phylogeny and classification at the generic level are not yet fully understood, and it is likely that Actinodaphne, Lindera, Litsea, Persea and Phoebe will need to be redefined when better molecular sampling of these genera is available. The family is sister to Hernandiaceae/Monimiaceae. Genera and species: Lauraceae include c. 45 genera and about 2,850 species: Actinodaphne (100), Aiouea (21), Alseodaphne (50), Aniba (41), Apollonias (2), Aspidostemon (c. 15), Beilschmiedia (c. 250), Caryodaphnopsis (16), Cassytha (20), Cinnadenia (2), Cinnamomum (c. 350), Cryptocarya (c. 200), Dehaasia (35), Dicypellium (2), Dodecadenia (1), Endiandra (106), Endlicheria (40), Eusideroxylon (2), Hypodaphnis (1), Kubitzkia (1), Laurus (2), Licaria (40), Lindera (100), Litsea (c. 400), Mezilaurus (20), Micropora (1), Nectandra (120), Neocinnamomum (6), Neolitsea (100), Nothaphoebe (40), Ocotea (c. 350), Paraia (1), Parasassafras (2), Persea (c. 200), Phoebe (100), Phyllostemonodaphne (1), Pleurothyrium (45), Potameia (30), Povedadaphne (1), Rhodostemonodaphne (20),

Sassafras (3), Sinosassafras (1), Umbellularia (1), Urbanodendron (1), Williamodendron (4) and Yasunia (2). Uses: Avocado, Persea americana, is a major crop around the world known for its tasty, nutritious fruits that are rich in vitamins, potassium and oils. Avocado oil is used for cooking (high in monounsaturated fats), cosmetics and lubrication. Enkala (Litsea garciae) is a minor fruit crop in tropical East Asia. Litsea cubeba has an edible fruit, and its leaves repel insects, although they can be used as food for silkworms. The bark of several Cinnamomum species is used as a culinary spice, predominantly true cinnamon (C. verum), cassia bark or bastard cinnamon (C. aromaticum), korintji cinnamon (C. burmannii) and kulilawan (C. culitlawan). Cinnamon oil is also used in incense, toothpaste and medicines. Camphor (C. camphora) is of economic importance as an insecticide, but the camphor used in mothballs is usually chemically synthesised. Cinnamaldehyde, the compound that gives cinnamon its flavour and odour, has numerous applications. Apart from flavouring beverages, food and chewing gum, it has been used as an effective fungicide in agriculture. It has also proved to be antimicrobial and has anticarcinogenic properties. It has even been used to prevent corrosion of steel. Bay (Laurus nobilis) is a well-known culinary herb used to flavour soups and stews. The plant was important in Classical Greek and Roman times when it was a symbol of victory, made into a wreath offered to gods, emperors and Olympic athletes. Cryptocarya moschata yields a spice known as Brazilian nutmeg. The bark and seeds of Madagascar cloves (Cryptocarya agathophylla) are used to flavour rum. Essential oils from the bark and seeds of several Cryptocarya species are extracted. Dicypellium caryophyllaceum bark produces a spice similar to cloves, but the species is not cultivated and now threatened with extinction due to overharvesting from the wild. Seeds of Actinodaphne hookeri, Licaria pulcheri (puchurin nut) and Nectandra pichurim (purchury bean) are used for (medicinal) oil. Oils of Nectandra

LAURALES

MAGNOLIIDS

Lindera umbellata var. membranacea Royal Botanic Gardens, Kew, UK [61]

Umbellularia californica, fruit, California, USA [61]

Cassytha filiformis, Singapore [61]

Cinnamomum verum, Helsinki Botanical Garden, Finland [61]

Persea americana, fruit, Kenya [61]

Cassytha filiformis, St Petersburg, Florida, USA [61]

Laurus nobilis, Hampton Court, England, UK [61]

elaiophora and Neolitsea sericea can be used for burning and making soap. Brazilian sassafras (Aniba roseodora) produces the famed bois-de-rose oil used in the perfume industry. Fragrant wood of Orinoco sassafras (Ocotea cymbarum) and camphorwood (O. usambarensis) are similarly exploited. Because of excessive harvesting from the wild, these species are now threatened with extinction. Spicebush (Lindera benzoin) and sassafras (Sassafras albidum) were used as teas by North American natives. Traditionally, they were used as a flavouring, but they are now banned because they have been linked to kidney cancer. Sassafras oil is still used as

a topical treatment for insect bites. Cassytha filifomis yields a brown dye. Many species produce good timber, and Persea nanmu is prized as a coffin wood in China. Endiandra palmerstonii wood is especially valued due to its varied colouration.

stems. They attach to the host via sucker-like cups that are formed singly or in files along the stem of the parasite and dissolve the underlying stem or leaf tissues of the host plant. They do make roots initially, but these die when a connection with the host plant is established.

Parasitism: The only parasitic genus is Cassytha, which has its centre of diversity in Australia where they are commonly referred to as dodder-laurels. They can become pests, especially in urban parks where vegetation remains free from fire; Cassytha species are fire-sensitive. The leafless stems coil tightly around the stems of a wide range of host plants, often forming dense mats of intertwining wiry

Etymology: Laurus is Latin for a bay tree. Crowns of bay branches were an emblem of victory or distinction, hence the term ‘laureate’. The word is a cognate with Δάφνη (Daphne), a Greek mythological nymph who flirted with the god Phoebus (hence the genus Phoebe), but when pursued, her mother Gaia changed her into a laurel bush.

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CHLORANTHALES

UNPLACED

CHLORANTHALES This order has long been controversial in terms of their relationships, with most authorities stating that their affinities are uncertain. They do not necessarily belong to the magnoliids, but in several molecular studies they are sister to them.

62. CHLORANTHACEAE Pearl-orchid family

This family is composed of aromatic herbs, shrubs and soft-wooded trees, with or sometimes without vessels in their stems. Their simple, opposite, petiolate leaves have dentate margins. Petioles are fused across the node at the base, and the stipules are fused with the petioles, sheathing the swollen stem nodes. The inflorescence is a terminal or axillary head, spike, thyrse or raceme that is usually compound. Flowers are usually subtended by up to three bracts and are unisexual (in Ascarina and Hedyosmum) or bisexual with the stamens adnate to one side of the ovary (in Chloranthus and Sarcandra). Three fused tepals are typical but sometimes absent. Male flowers have one to five stamens, with the connective

Ascarina rubricaulis, Plateau de Dogny, New Caledonia (CD) [62]

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often enlarged. Female and bisexual flowers have inferior ovaries or are naked. Bisexual flowers have one to three fused anthers that are connected to and sometimes envelop the ovary. The ovary has a single carpel with a short style and (nearly) sessile stigma. The fruit is a berry or drupe, and the seeds have a hard seed coat. Distribution: This family occurs in tropical America, Madagascar, tropical and temperate East Asia, New Guinea, New Caledonia, New Zealand and on Pacific islands. Chloranthaceae are absent from mainland Africa. Phylogeny and evolution: Affinities of this family have been much disputed in the past. They were placed in Piperales, Magnoliales and Laurales, and even an association with Trimeniaceae or the monocots has been suggested. Molecular analyses (based mostly on plastid DNA) have placed them in an isolated position as sister to the magnoliids, and they are now placed in their own order Chloranthales. Fossils of this family are common, world-wide in distribution and morphologically diverse. The spiraperturate pollen is unique to the family and easily recognised in pollen deposits; the oldest

Chloranthus holostegius, Kunming Botanical Garden, China [62]

pollen fossils are from the Early Cretaceous, c. 125 million years old, and can be attributed to Hedyosmum. All modern genera diverged c. 90 million years ago, and diversification of Hedyosmum in the New World is estimated to have occurred c. 35–45 million years ago, coinciding with the uplift of the Andes. Chloranthaceae were, however, more diverse in earlier times and show a pattern of extinction and recent radiation. Genera and species: Chloranthaceae include four genera with 77 species: Ascarina (12), Chloranthus (18), Hedyosmum (45) and Sarcandra (2). Uses: The leaves of Chloranthus glabrus and C. spicatus are used to scent tea or added to tea for bulk. Chloranthus erectus was used in Java instead of tea, before tea (Camellia) was introduced there. The leaves have detoxifying and anti-inflammatory properties, and several species of Chloranthus are used in Asian traditional medicine. Etymology: Chloranthus is derived from Greek χλωρός (chloros), green, and άνθος (anthos), flower.

Hedyosmum mexicanum, male, Mexico [62]

Hedyosmum mexicanum, female, Guatemala [62]

MONOCOTS Monocots or monocotyledons were first recognised as a natural group of plants by John Ray (Methodus Plantarum Nova, 1682), who was the first to emphasise the differences between the number of seed leaves (cotyledons, one versus two) among flowering plants. The dicots or dicotyledons (usually) have two seed leaves, but they are not monophyletic because they include the ANA grade magnoliids and eudicots; basically dicots include all angiosperms minus the monocots. The monocots are a clade and are recognised by the APG classification (2009), but there is no single or set of morphological characters that are guaranteed to inform an observer that a plant is a monocot. Having made this

point, most monocots have leaves with parallel veins, an embryo with a single cotyledon (which may be retained in the seed as an absorbtive organ, so you cannot see it, as in grasses), adventitious roots (the tap root aborts at an embryonic stage), stems with scattered vascular bundles (not in a ring) and a particular type of sieve cell plastids. One can add to this set that monocot flowers are often in threes, but this also occurs widely in the magnoliids and some eudicots. Exceptions to these are frequent among monocots; for example, most members of Pandanales have tetramerous flowers, and several forest-adapted monocots have leaves with reticulate venation. Possession of

the last must be qualified by stating that all monocot leaves are derived from the apex of the leaf primordium, which perhaps could be considered the best candidate for an unqualified monocot synapomorphy. It is not, however, a feature that you can see with the naked eye or even a hand lens, so it is really not all that helpful to the field botanist. Much has been made about a possible aquatic origin for the monocots, and it seems clear that among the early diverging lineages are a large number of taxa that are either aquatic (many Alismatales) or inhabit wet habitats. The same argument has been advanced for the angiosperms as a whole, pointing in particular to

A landscape dominated by monocot families, Chapada Diamantina, Bahía, Brazil , including Arecaceae, Bromeliaceae, Cyperaceae, Orchidaceae, Poaceae and especially Velloziaceae

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MONOCOTS

Nymphaeales, but it is also clear that the taxa comprising these early-diverging clades are relictual and perhaps not representative of the characteristics of their ancestors. The answers to these questions can probably be established by further study of the fossil record and perhaps by understanding patterns of gene expression, but at present it seems unwise to come down clearly on one side of this debate. We prefer to see these as exciting directions for further research. From the study of whole plastid genome sequences, the position of the monocots seems to be as sister to Chloranthaceae, eudicots or the magnoliid clade, and studies of many low-copy nuclear genes are not yet far enough advanced to provide a robust answer to the question of what are the closest relatives of monocots. What is clear is that monocots represent the earliest major radiation of angiosperms; they have collectively conquered all ecological zones on the planet, including marine and freshwater systems, deserts and edges of glaciers. Monocots occur in both polar zones and dominate landscapes across the planet. They include some of the smallest and some of the largest angiosperms – some of the largest palms can individually be seen from orbiting satellites, which is even more remarkable when realising that they are really giant herbs that do not have secondary growth in their trunks. There are tree-forming monocots with secondary growth, albeit a type termed ”anomalous”, such as in agaves, aloes, cordylines, Joshua trees and other yuccas. Finally, some monocots are among the most adaptable and productive domesticated organisms on earth, providing us with food, fibres, medicines and building materials. It is difficult to imagine how seven billion people could be fed if it were not for the efficient production of starch and sugar by grasses (wheat, rice, maize, sugarcane and others). Other monocots 116

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General references: Chase MW. 2004. Monocot relationships: an overview. American Journal of Botany 91: 1645–1655. Chase MW, Soltis DE, Olmstead RG, Morgan D, Les DH, Mishler BD, Duvall MR, Price RA, Hills HG, Qiu YL, Kron KA, Rettig JH, Conti E, Palmer JD, Manhart JR, Sytsma KJ, Michaels HJ, Kress WJ, Karol KG, Clark WD, Hedrén M, Gaut BS, Jansen RK, Kim KJ, Wimpee CF, Smith JF, Furnier GR, Strauss SH, Xiang QY, Plunkett GM, Soltis PS, Swensen SM, Williams SE, Gadek PA, Quinn CJ, Eguiarte LE, Golenberg E, Learn GH Jr, Graham SW, Barrett SCH, Dayanandan S, Albert VA. 1993. Phylogenetics of seed plants: an analysis of nucleotide sequences from the plastid gene rbcL. Annals of the Missouri Botanical Garden 80: 528–580. Chase MW, Fay MF, Devey D, Maurin O, Rønsted N, Davies J, Pillon Y, Petersen G, Seberg O, Tamura MN, Asmussen

CB, Hilu K, Borsch T, Davis JI, Stevenson DW, Pires JC, Givnish TJ, Sytsma KJ, McPherson MA, Graham SW, Rai HS. 2006. Multigene analyses of monocot relationships: a summary. Aliso 22: 63–75 Columbus JT, Friar EA, Porter JM, Prince LM, & Simpson MG (eds). 2006. Monocots: comparative biology and evolution, excluding Poales. Rancho Santa Ana Botanical Garden, Claremont (Aliso 22). Dahlgren RMT, Clifford HT, Yeo PF. 1985. The families of the monocotyledons. Springer, Berlin. Duvall MR, Clegg MT, Chase MW, Lark WD, Kress WJ, Hills HD, Eguiarte LE, Smith JF, Gaut BS, Zimmer EA, Learn GH Jr. 1993. Phylogenetic hypotheses for the monocotyledons constructed from rbcL sequences. Annals of the Missouri Botanical Garden 80: 607–619. Ray J. 1682. Methodus plantarum nova. Faitborne & Kersey, London. Rudall PJ, Cribb PJ, Cutler DF, Humphries CJ (eds). 1995. Monocotyledons: systematics and evolution. Royal Botanic Gardens, Kew. Wilson KL, Morrison DA (eds). 2000. Monocots: systematics and evolution. CSIRO, Collingwood.

Grove of Livistona mariae subsp. rigida, Joe Creek, Judbara-Gregory National Park, Northern Territory, Australia

Maarten Christenhusz holding a fruit of coco-demer, Lodoicea maldivica, containing the largest seed in the world, Praslin, Seychelles

also provide staple foods, such bananas, dates, yams and taro, but this pales in comparison to food produced by grasses, especially when fodder for grazing animals is included.

ACORALES

MONOCOTS

ACORALES This small order consists of a single family of rhizomatous, sweet-smelling herbs with aromatic oil cells. They are sister to all other monocots.

63. ACORACEAE Sweet-flag family

These plants have leaves that are organised in a fan at the tips of much-branched, functionally vessel-less rhizomes. The leaves are narrow, sword-shaped, unifacial (with an internal morphology that is the same on both surfaces) and without stipules, but the blades are intercalated and sheathing at the base (i.e. equitant). Veins are strictly parallel. Inflorescences are a solitary spadix (without a spathe in contrast to Araceae; see below) borne laterally on a leaf. The conical fingeror tail-like spadix is densely covered with flowers that are partly sunken in the spadix Acorus gramineus, fruits, Mt Tianmu, Anhui, China [63]

axis. The flowers are bisexual and lack bracts. They are trimerous, with the six thin petals clasping the stamen filaments. Six stamens are in two whorls of three, have linear filaments and rounded anthers that sit atop the clasping petals and open via a longitudinal slit. The bi- or trilocular ovary is superior with a sessile stigma. The fruit is a berry with a leathery skin and holds one to five (to nine) oblong to ellipsoidal seeds. Distribution: This is a family comprised of a single genus perhaps native to East and Southeast Asia. It also occurs throughout Europe and North America, but it has been naturalised in Europe and Egypt since ancient times and has become part of the flora in those parts. Phylogeny and evolution: Acorus was for most of its history placed in Araceae, but there is a long list of technical characters that separate them, and it has now been shown that the families are not at all closely related. Acoraceae are isolated and sister Acorus calamus, Ruissalo Botanical Garden, Turku, Finland [63]

to all other monocots and thus placed in their own order Acorales. Macrofossils of Acorus and Acorites are known from the Eocene of North America and Europe. The age of the crown group is estimated to be c. 20 to 50 million years old, whereas the stem lineage is closer to 130 million years old. Genera and species: Acoraceae consist of the single genus Acorus with two species: Acorus calamus and A. gramineus. Uses: Dried rhizomes of Acorus calamus, known as rhizoma calami, have been used for eye and stomach ailments, and were already in use by the ancient Egyptians. Tea from the chopped roots is said to help digestive problems and can remove phlegm from the lungs; it clears congestion and “tranquilises” the mind. Calamus oil is still used in medications today; it contains high levels of β-asarone, which can be effective in the treatment of neurological diseases. Prolonged exposure to this compound is toxic, and this oil is therefore not deemed suitable for human consumption. It should not be used internally without expert supervision. It has been marketed as ‘legal ecstasy’ due to its hallucinogenic effect in large concentrations. Its roots have also been used in perfumes and liqueurs and as a poor-man’s substitute for ginger, cinnamon and nutmeg. Acorus gramineus has been used for similar purposes in East Asia. Etymology: Acorus is derived from ακορών (acoron), the name used by Dioscorides to describe the root of sweet flag, which was initially confused in Europe with the yellow flag iris (Iris pseudacorus); both were used medicinally to treat inflammation of the eyes. The name was derived from the Greek κόρης (koris), pupil.

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ALISMATALES

MONOCOTS

ALISMATALES Families 64 to 77 comprise the order Alismatales, an order that is approximately 125 million years old. The order is composed of predominantly hydrophytes, plants associated with water, although in the large family Araceae, epiphytes, lianas and geophytes have also evolved. The order also includes a number of seagrass families, one of the few vascular plant clades that include submerged marine species. Many small families have been recognised in this order due to their striking and different adaptations to aquatic habitats.

Wolffia arrhiza, Helsinki Botanical Garden, Finland [64]

Gymnostachys anceps, New South Wales, Australia [64]

Lysichiton americanus, Bodnant Gardens, Wales, UK [64]

64. ARACEAE

small leaf-like structures that are poorly differentiated, usually one or several clustered to 18 mm long, surrounded by a bifid scale or not. These structures can be veined or not and can have roots or not. Leaves of other Araceae are usually differentiated into a petiole and blade that can be variable in shape, the primary venation usually pinnate, but often pedate or palmate at the base, or parallel, the secondary venation usually net-veined. The leaf is flat and without a petiole in Gymnostachyoideae. Inflorescences are usually composed of a spadix, a spike in which the small flowers are sessile on or sunken into the axis, which is surrounded by a spathe, a leaf that has a specialised shape that is often colourful, although the spathe is difficult to observe in Gymnostachys, Orontium and Lemnoideae. Lemnoideae have reproductive pouches in

the blade, which are enclosed by a cap, and the bisexual flowers are one or two per blade, with one or two stamens and a bottle-shaped unilocular ovary per flower. The flowers in other Araceae are usually sessile, bisexual or unisexual. When unisexual, the female flowers are usually at the base of the spadix and the male flowers are in the middle or at the tip, sometimes separated from the female flowers by sterile flowers. The reduced petals are free, partly fused or completely fused and are in a single whorl. Stamens are usually in two whorls of two or three, sometimes fewer or more, free or fused. The superior ovary is composed of one to three (or more) fused carpels, with a short or absent style and a wet stigma. The fruit is a berry that is rarely dehiscent, borne on the fleshy spike and rarely with the berries fused into a syncarp, often with oxalate crystals.

Calla-lily family

This varied family consists of terrestrial, epiphytic or aquatic herbs that can be diminutive to enormous, self-supporting, climbing or free-floating. Geophytic species make stem tubers. They can have true or false stems, mature shoots often forming a sympodium. Duckweeds, the free-floating members of Lemnoideae, are reduced to 118

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MONOCOTS

Spathiphyllum wallisii, Guadeloupe [64]

Typhonium giganteum, Royal Botanic Gardens, Kew, UK [64]

Zantedeschia aethiopica naturalised along the coast near San Francisco, California, USA [64]

Distribution: Araceae have a near global occurrence due to the wide distribution of Lemnoideae. The family is absent from permanently dry and frozen regions, and it is most diverse in the tropics.

the broad sense are monophyletic): Gymnostachyoideae – Gymnostachys (1); Orontioideae – Lysichiton (2), Orontium (1) and Symplocarpus (5); Lemnoideae – Lemna (13), Spirodela (4), Wolffia (11) and Wolffiella (10); Aroideae – Aglaodorum (1), Aglaonema (22), Alloschemone (2), Alocasia (80), Ambrosina (1), Amorphophallus (c. 200), Amydrium (5), Anadendrum (12), Anaphyllopsis (3), Anaphyllum (2), Anchomanes (6), Anthurium (c. 940), Anubias (8), Apoballis (12), Aridarum (10), Ariopsis (2), Arisaema (c. 180), Arisarum (3), Arophyton (7), Arum (c. 30), Asterostigma (8), Bakoa (3), Biarum (21), Bognera (1), Bucephalandra (2), Caladium (14), Calla (1), Callopsis (1), Carlephyton (3), Cercestis (10), Chlorospatha (28), Colletogyne (1), Colocasia (8), Croatiella (1), Cryptocoryne (60), Culcasia (27), Cyrtosperma (12), Dieffenbachia (57), Dracontioides (2), Dracontium (24), Dracunculus (2), Eminium (9), Epipremnum (15), Fenestratarum (2), Filarum (1), Furtadoa (2), Galantharum (1), Gearum (1), Gonatopus (5), Gorgonidium (8), Hapaline (8), Helicodiceros (1), Hestia (1), Heteropsis (17), Holochlamys (1), Homalomena (124), Incarum (1), Jasarum (1), Lagenandra (15), Lasia (2), Lasimorpha (1), Leucocasia (1), Lorenzia (1), Mangonia (2), Monstera (40), Montrichardia (2), Nephthytis (6), Ooia (2), Pedicellarum (1), Peltandra (2), Philodendron (c. 490), Phymatarum (1), Pichinia

(1), Pinellia (9), Piptospatha (12), Pistia (1), Podolasia (1), Pothoidium (1), Pothos (56), Protarum (1), Pseudohydrosme (2), Pycnospatha (2), Remusatia (4), Rhaphidophora (c. 100), Rhodospatha (29), Sauromatum (9), Scaphispatha (2), Schismatoglottis (107), Schottariella (1), Scindapsus (35), Spathantheum (2), Spathicarpa (3), Spathiphyllum (50), Stenospermation (50), Steudnera (9), Stylochaeton (20), Synandrospadix (1), Syngonium (34), Taccarum (6), Theriophonum (7), Typhonium (69), Typhonodorum (1), Ulearum (2), Urospatha (11), Vietnamocasia (1), Xanthosoma (75), Zamioculcas (1), Zantedeschia (8), Zomicarpa (2) and Zomicarpella (2).

Phylogeny and evolution: The duckweeds, Lemnoideae (former Lemnaceae), are sister to Aroideae, with Orontioideae and Gymnostachyoideae (with genera always included in Araceae) successively sister to this clade. Calla palustris is difficult to place on morphological and molecular grounds, but nevertheless belongs to Aroideae, in spite of having bisexual flowers. Fossils of Aroideae have been found in Palaeocene and Eocene sediments. Fossils of Limnobiophyllum, interpreted as an intermediate stage between Lemnoideae and Aroideae are known from the Late Cretaceous, but the family is estimated to be of greater age, c. 122 million years old. It was long believed that the duckweeds evolved through Pistia, which indeed has striking similarities in developmental stages to Spirodela. This resemblance is superficial, and it is now known that the two are not closely related. Genera and species: Araceae consist of 118 genera and c. 3,300 species, divided in four subfamilies, with Aroideae sometimes divided into a further five subfamilies (not followed here, given that Aroideae in

Uses: All Araceae have calcium oxalate crystals, and therefore the fruit, leaves and tubers have to be consumed with care. The crystals can often be removed by boiling with a pinch of baking soda or by soaking in cold water overnight. Taro is the edible tuber of several species of Araceae, of which Colocasia esculenta, native to South Asia, is the most commonly and most widely cultivated species. The giant taro or elephant ear, Alocasia macrorrhizos, the domesticated form of which is native to the Philippines, is also edible after cooking the stems for a considerable length of time. Taro is a staple food for several groups of Pacific islanders and is now also cultivated in Plants of the World

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sterile flowers male flowers female flowers

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Calla palustris, Ruissalo Botanical Garden, Turku, Finland [64]

Amorphophallus titanum, Royal Botanic Gardens, Kew, UK [64]

The aroid inflorescence, with female flowers at the base of the spadix, male flowers above and sterile flowers closing the opening of the spathe. Arum maculatum, Lleyn Peninsula, Wales, UK [64]

East Africa. Pulaka, Cyrtosperma merkusii, is another food crop from the Pacific, where it is grown in fresh-water swamps in atolls and is often the only source of starch there. The arrowleaf elephant ear, Xanthosoma sagittifolium, originated in tropical America and is used for various dishes, such as alcapurrias, mondongo, pasteles and sancocho; it is also an important ingredient of Surinamese pom. Leaves are also edible after cooking and called taioba in Brazil. Konjac or konnyaku, Amorphophallus rivieri, is used in Japanese cuisine as (shirataki) noodles. The flavourless jellylike substance is also used to make fruit candy and because konjac has almost no calories, it is used as a diet food. The Swiss-cheese plant, Monstera deliciosa from Central America, is a commonly grown houseplant in temperate regions. It has an edible fruit that looks like a pineapple and has a sweet flavour. Species of Cryptocoryne and Pistia stratiotes are popular aquarium plants. Orontium aquaticum, Calla palustris, Lysichiton americanus, L. camtschatcense and Zantedeschia aethiopica are commonly offered in garden centres as pond plants. Duckweeds have high protein content, and because of their rapid vegetative reproduction they are sometimes grown as a crop for animal fodder. Wolffia globosa is consumed by people in Southeast Asia, and Lemna gibba is eaten as a vegetable in the Levant. Some aquatic species accumulate nutrients

and pollution from water and are used for waste water management. The plants are also composted, releasing nutrients for crop plants. Many species of Araceae are attractive and make good garden or house plants. The most popular are species of Aglaonema, Alocasia, Amorphophallus, Anthurium, Arisaema, Caladium, Colocasia, Dieffenbachia, Epipremnum, Monstera, Philodendron, Sauromatum, Scindapsus, Spathiphyllum, Syngonium, Zamioculcas and Zantedeschia, but other genera may also be on offer from specialist nurseries. Anthurium and Zantedeschia flowers are commonly grown for the cut-f lower industry. A great variety of colour forms of ‘anthuriums’ and ‘calla-lilies’ have been bred for this purpose.

arums frequently feature in news items when they flower in a botanical garden, where they spread their powerful foetid fragrance.

Christenhusz, Fay & Chase

Smallest plants: Wolffia angusta and W. globosa are the smallest species of vascular plants, with the entire plant being 0.8 × 0.4–0.6 × 0.7–1.0 mm. Lemnoideae are usually distributed between fresh water bodies by currents and by sticking to the legs and feathers of water fowl. They mostly spread vegetatively and only rarely reproduce by seeds. The big stink: The titan arum, Amorphophallus titanum, from Indonesia, produces not only enormous umbrella-like leaves, but also a two-metre tall spadix, the largest unbranched inflorescence of any plant. Flowering titan

Kettle traps: Plants with unisexual flowers and complex spathes have a specialised pollination syndrome called the ‘kettle trap mechanism’. In genera including Arisaema, Arisarum, Arum, Cryptocoryne and Philodendron, the female flowers are at the base of the inflated spathe and the male flowers are above, with sterile, down-pointing and hair-like flowers in between or above. The tip of the spadix often produces a scent attracting pollinators, and the spadix can be a few degrees warmer than the surroundings. The pollinators get trapped in the chamber with the female flowers until these are pollinated and the sterile flowers shrivel, during which time the anthers ripen and cover the insects with pollen on their way out of the chamber. Much less is known about the pollination mechanisms of species with bisexual flowers, but in these the flowers must provide other attractants for the insects to remain on the inflorescence. Etymology: Arum is the Roman name for the arum-lily, most likely derived from Greek άρον (aron), also the name for the plant in ancient Greek. Aaron is also the name of the brother of Moses in the Bible, but the name of the plant is not a cognate with the biblical name, which is of Egyptian origin.

ALISMATALES

MONOCOTS

65. TOFIELDIACEAE False-asphodel family

spathe-like bract. The actinomorphic flowers are subtended by bracteoles, which are simple or forked. The six tepals are free or basally fused and usually persistent in fruit. The six or nine stamens are usually free or basally fused, with filaments that are sometimes shorter, but often longer than the petals. The superior ovary has three carpels fused only at the base, each carpel topped with a short style. Fruits are septicidal capsules containing five to numerous seeds.

Tofieldiaceae are perennial rhizomatous herbs. The linear leaves are persistent and mostly basally arranged in a flat fan. The inflorescence has up to four leaves, topped by a raceme or spike, sometimes surrounded by a

Distribution: This North Temperate family occurs mainly in boreal and montane regions, extending south into the southeastern USA, Japan and China, with isolated populations in the northern Andes and Guayana Highlands.

Tofieldia coccinea, Crûg Farm Plants, Wales, UK [65]

Triantha occidentalis subsp. montana, Valley County, Idaho, USA (CD) [65]

Phylogeny and evolution: Tofieldiaceae are dated to have diversified c. 100 million years ago. Pleea is sister to the rest of the family. They were previously included in Nartheciaceae or even in a broad concept of Liliaceae, but these genera are not closely related to either; they form an isolated lineage within Alismatales. Genera and species: This family has four genera and c. 30 species: Harperocallis (14), Pleea (1), Tofieldia (12) and Triantha (4). Etymology: Tofieldia was named for Thomas Tofield of Wilsick (1730–1779), a British botanist and civil engeneer.

Tofieldia calyculata in fruit, private garden, Kingston upon Thames, Surrey, UK [65]

Tofieldia calyculata, private garden, Kingston upon Thames, Surrey, UK [65]

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66. ALISMATACEAE Water-plantain family

This is a family of aquatic, monoecious and dioecious plants that are rooted in the soil under fresh water and have stems that are emergent, submersed or floating. They can be annual but are usually perennial. Stems grow underground or under water (rhizomes) and can have stolons and fibrous roots, often forming a corm. Juice is milky in many species. Aerial stems are fleshy when present. Leaves form a basal rosette, are spirally arranged or are whorled along the stems, usually with a petiole, variable in shape and size, especially between submerged, floating and emergent leaves. Petioles are rounded to triangular, often longer than the blade and sheathing basally. Blades are linear, orbicular, lanceolate or sagittate, the bases usually cordate, sagittate or hastate, sometimes attenuate, the apices blunt, acute or

Alisma plantago-aquatica, Ruissalo, Finland [66]

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MONOCOTS

acuminate, the margins entire and sometimes wavy. Primary veins arch from the base to the apex, diverging where the leaf blade widens, with transverse secondary veins forming a regular net-veined pattern. Inflorescences are erect and emergent or floating, and they are usually umbels that are often in a whorled raceme or panicle. Flowers are regular, with three persistent and green sepals and three coloured delicate petals. There are six, nine or many free stamens, and these have bilocular, basifixed or versatile anthers. The ovary is superior and has three to many carpels that are free or basally fused. The fruit is a dry achene or follicle. The numerous seeds are glandular, ridged and U-shaped. Distribution: This family has a nearly global occurrence, but it is absent from most arid areas. Phylogeny and evolution: Alismataceae evolved during the Late Cretaceous (c. 80 million years ago) and are deeply split into two clades, one corresponding to Alisma, Baldellia, Damasonium and Luronium, the other including all other genera and the former family Limnocharitaceae. Echinodorus is polyphyletic with regard to Sagittaria, hence acceptance of Albidella and Helanthium as

separate genera, but the type species Echinodorus berteroi is morphologically different from the other species, which may result in the majority of Echinodorus requiring a new generic name. Genera and species: This family of 17 genera has c. 115 species: Albidella (1), Alisma (8), Astonia (1), Baldellia (3), Burnatia (1), Butomopsis (1), Caldesia (4), Damasonium (6), Echinodorus (30), Helanthium (3), Hydrocleys (5), Limnocharis (2), Limnophyton (5), Luronium (1), Ranalisma (2), Sagittaria (39) and Wiesneria (3). Uses: Leaves of Limnocharis flava are eaten as a vegetable in tropical Asia. Sagittaria sagittifolia has an edible corm and is cultivated for that purpose in East Asia. Sagittaria latifolia roots were used by native Americans as a food source. Several Echinodorus and Helanthium species are commonly grown as aquarium plants, and species of Alisma, Echinodorus and Sagittaria are grown as pond ornamentals, especially in the tropics and subtropics, where they frequently naturalise in aquaculture. Etymology: Αλισμα (alisma) is an Ancient Greek name for a water plant.

Echinodorus grandiflorus, Helsinki Botanical Garden, Finland [66]

Limnocharis flava, Ruissalo Botanical Garden, Turku, Finland [66]

Hydrocleys nymphoides, Tahiti [66]

Luronium natans, Royal Botanic Gardens, Kew, UK [66]

ALISMATALES

MONOCOTS

67. BUTOMACEAE Flowering-rush family

are superior and composed of six carpels in two whorls that are fused at the base only. Fruits are dry separate follicles that open by central slits and contain numerous ribbed, straight seeds.

68. HYDROCHARITACEAE Frogbit family

Distribution: This family is restricted to temperate Eurasia, but is naturalised in eastern North America.

These freshwater perennials have creeping rhizomes with axillary buds that may develop into bulbils with which they can spread in their aquatic habitat. Leaves are borne on the apex of rhizomes and are somewhat arranged in a plane. Leaves lack petioles and are sheathing basally and linear, triangular in transverse section at the base but flattening towards the apex and up to a metre long. Inflorescences emerge from either side of rhizomes among leaves and are erect and composed of an umbellike complex of cymes, which are subtended by c. three bracts. The actinomorphic flowers are stalked and trimerous. The three sepals are darker pink than the three whitish pink petals, which are all free. The nine pink stamens are in two whorls: the outer of six and the inner of three stamens with basifixed anthers. Ovaries

Phylogeny and evolution: The family used to include Butomopsis, Hydrocleys and Limnocharis, but molecular phylogenetic studies placed these genera firmly in Alismataceae. Fossils attributed to this family are often inconclusive. The family is sister to Hydrocharitaceae. Genera and species: This family includes a single species, Butomus umbellatus. Uses: The starchy rhizomes are eaten in some parts of Russia where they are mixed with grain to make bread or cooked as a vegetable. Etymology: Butomus is derived from ancient Greek βους (bous), an ox, and τομος (tomos), to cut, in reference to leaves that cannot be eaten by cattle because their sap blisters the mouth.

Butomus umbellatus, Ruissalo Botanical Garden, Turku, Finland [67]

These aquatics are annual and perennial, unisexual and bisexual herbs. They have simple or complex branched stems, and the leaves are whorled, spirally arranged or distichous (in a single plane). Leaves are simple, leaf-like or scale-like, and can have thin translucent stipules (not always present). Petioles can be short or elongate, winged or not and are sometimes sheathing at the base or not clearly defined from the leaf base. Leaf blades are submerged or floating, rarely emergent, linear to round or heart-shaped. Venation is often with parallel main veins and numerous cross-veins; the margin is entire or dentate, but sometimes with spines. Inflorescences are sessile or stalked. They develop inside one or two, free or united bracts that are often called a spathe. Inflorescences are composed of one or more monochasia, often with complex arrangements. Flowers are emergent, at the water surface, or submerged (see pollination below). Flowers are bisexual or unisexual, regularly actinomorphic or becoming zygomorphic. Male flowers can become detached before anthesis and float to the female flowers or are persistent on the plant with floating pollen. Female flowers are retained on the mother plant. Bisexual flowers are often selfing without opening (cleistogamous). Perianths are present and showy, evanescent or absent (Najas), and sepals are free, three (or absent). Petals are usually three or fewer, sometimes absent, often large and showy. Stamens are usually formed in six whorls of three, sometimes fewer or partly staminodial and in some cases reduced to a single stamen. Ovaries are inferior, with three to 20 carpels, with as many styles as carpels. Nectaries, if present, are three and formed at the base of the

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ALISMATALES styles. Peduncles are often curved or spiralling, pulling the developing fruit under water. Fruits are berries, regularly or irregularly dehiscing fleshy capsules or achenes (Najas). Seeds are cylindrical or ellipsoidal and have a complex outer structure. Distribution: This widespread family is distributed across North America, the Caribbean, northern South America, southern Brazil, temperate Eurasia, Sub-Saharan Africa, Madagascar, the Indian Ocean, South and Southeast Asia north to Japan, Malesia south

Ottelia ovalifolia, Victoria, Australia (JC) [68]

MONOCOTS

to Australia, New Guinea and throughout the Pacific to French Polynesia and Hawaii. Phylogeny and evolution: Hydrocharitaceae evolved c. 75–65 million years ago, probably originating in Asia. The seagrass clade evolved much more recently, 19 million years ago. Stratiotes dates back to the Mid Eocene with a fossil record of 48 million years, exhibiting little morphological variability. Hydrocharitites and Hydromystria are Miocene and Tertiary fossils similar to extant Hydrocharis dubia. Najas guadalupensis, Payette Lake, Idaho, USA (CD) [68]

Egeria najas, Copenhagen Botanical Garden, Denmark [68]

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Najas has been difficult to place on morphological grounds, due to its extreme reduction and adaptations to aquatic pollination. For this reason, it was often placed in its own family Najadaceae. DNA analyses in the 1990s demonstrated that Najas belongs to Hydrocharitaceae, despite several morphological and anatomical differences. This affiliation was already suggested in the 1930s, although an association with the seagrasses was later more commonly assumed.

Hydrocharis morsus-ranae, private garden, Kingston upon Thames, Surrey, UK [68]

Vallisneria americana, Helsinki Botanical Garden, Finland [68]

ALISMATALES

MONOCOTS

Genera and species: The family consists of c. 16 genera and c. 130 species of fresh water and marine aquatics: Appertiella (1), Blyxa (12), Egeria (3), Elodea (6), Enhalus (1), Halophila (19), Hydrilla (1), Hydrocharis (3), Lagarosiphon (9), Limnobium (2), Najas (36), Nechamandra (1), Ottelia (19), Stratiotes (1), Thalassia (2) and Vallisneria (14). Uses: Leaves and inflorescences of Ottelia cordata are eaten in Southeast and East Asia. Some species are popular pond and aquarium plants, and several of these have escaped into nature: Egeria densa (largeflowered waterweed) from South America in waterways in the Northern Hemisphere and Australasia; Elodea canadensis (Canadian waterweed), probably one of the most infamous invasives, blocking waterways in Europe and later being replaced by an invasion of North American Elodea nuttallii; Hydrilla verticillata creating havoc in the southern USA; frogbit (Hydrocharis morsusranae) from Europe in Canada, where it also has created water management issues; South African Lagarosiphon major becoming a pest in New Zealand; and Asian tapegrass (Vallisneria) creating problems in irrigation canals even within its natural range. Several species of Egeria, Elodea, Hydrocharis, Stratiotes and Vallisneria are still commonly offered in the aquarium and pond plant trade, often as oxygenating plants. Elodea can be used to remove pollutants from bodies of water and as a nutritious fodder for animals. Pollination: There are five major mechanisms of pollination. Insect-pollinated species have large showy flowers and nectaries, with male and female flowers alike. In Blyxa the flowers are insect-pollinated as well, but the flowers do not offer a reward. The female flowers mimic the male flowers but have petaloid styles that resemble the petals of the male flower, whereas the petals of the female flowers are reduced and thread-like. These petaloid structures exude a fluid, and the wetted pollen is transported by carnivorous insects that are attracted by the dead insects in the fluid. In Limnobium, pollen is winddispersed. Male flowers are held above the

females. Hydrilla verticillata has explosive anthers. Female flowers form an inverted bell under water, but open to the air, the inside being hydrophobic and the stigma remaining dry. Only pollen landing directly in the bell is effective in pollination. A number of genera have flowers on the water surface. In these species the male flowers are free-floating or the pollen floats, reaching the female flowers that rest on the water surface. Sepals are water repellent, causing changes in the surface tension of the water, allowing the pollen to be drawn in by the female flowers. In the submerged and marine genera Halophila, Thalassia and Najas, flowers are reduced and pollen released in gelatinous, stringy masses, which are picked up by submerged or superficial female flowers. Etymology: Hydrocharis is derived from the Greek ύδωρ (hydor), water, and χάρης (charis), grace.

69. SCHEUCHZERIACEAE Rannoch-rush family

Scheuchzeria palustris, Kittilä, Finland (HV) [69]

These perennial plants have horizontal rhizomes, clothed in old leaf bases, rooting from the nodes. Stems are erect with alternate leaves. The sheathing base is open and has two delicate protrusions at the tip of the sheath at the base of the linear blade. The blade has several parallel veins. Inflorescences are simple racemes with bracts subtending the pedicels. Flowers are bisexual, actinomorphic, with six tepals all similar, free and lanceolate-elliptic. Six stamens are free and dehisce by longitudinal slits. Ovaries are superior, the carpels three (sometimes six), mostly free (fused at the base only), with sessile stigmas. The fruit is composed of three dehiscing follicles with one or two seeds.

Distribution: This circumarctic inhabits sphagnum bogs.

family

Phylogeny and evolution: They appear morphologically similar to Juncaginaceae and associated families, but despite a shared chemistry (triglochinin) these are not sister groups. Genera and species: This family consists of a single species, Scheuchzeria palustris. Etymology: Scheuchzeria was named in honour of Swiss physician and scholar Johann Jakob Scheuchzer (1672–1733), who was well known for his accounts of the natural phenomena of Switzerland.

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ALISMATALES

MONOCOTS

Aponogeton distachyos, private garden, Kingston upon Thames, Surrey, UK [70]

Triglochin bulbosa, Western Australia [71]

Triglochin bulbosa, Western Australia [71]

Cycnogeton procerum, Royal Botanic Gardens, Kew, UK [71]

70. APONOGETONACEAE

Petals are not differentiated; they can be absent but there are usually two to six. Stamens are usually six (absent in female plants). The ovary is superior, composed of three, free, sessile carpels; the stigma is a ridge on the side of the short-styled carpel, rudimentary in male plants (rarely). The fruit is a follicle with a curved beak, submerged until seeds are released after decay, after which the seeds may float for a short while and sink in a new spot. Seeds have no dormancy.

are considered a delicacy and commonly cultivated as waterblommetjies (‘water flowers’) for this purpose in South Africa. The cooked inflorescences have a meaty flavour. The starchy tubers of several species can be eaten by humans and livestock. Several other species are frequently grown as aquarium or pond ornamentals.

Waterblommetjie family

These perennial fresh water aquatic plants are rarely dioecious and have an underground stem and a starchy rootstock or rhizome. Leaves are spirally arranged in a rosette around the tip of the rhizome and are submerged or floating (rarely emergent). Leaves are usually stalked, and the blade is oval with rounded tips and apices. Venation is parallel, merging at the tip and base of the leaf, with parallel secondary cross-venation. In some species the leaf tissue between the veins is absent, forming a net. Inflorescences are long-stalked, emergent and bracteate, the bracts covering the inflorescence branches in bud. The inflorescence is spicate and can be composed of one to several spikes. Flowers are sessile on the bracteate spikes, more or less spirally arranged or sideways.

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Distribution: A family found in Sub-Saharan Africa, Madagascar, South and Southeast Asia, Malesia, New Guinea and Australia. Phylogeny and evolution: Aponogetonaceae belong to the clade including the seagrasses and Juncaginaceae, in which they are an early-branching lineage. The vegetative morphology is similar to that of Potamogetonaceae, and the group has often been associated with that family.

Etymology: Aponogeton is composed of the name of a Roman spring, the Aquae Aponi, near Padua, Italy (in turn from Greek απονος, aponos, painlessness or heartlessness), and the Greek γειτον (geiton), a neighbour.

71. JUNCAGINACEAE Arrowgrass family

Genera and species: The single genus Aponogeton has 56 species. Uses: Inflorescences and flower buds of Cape pondweed (Aponogeton distachyos)

This is a family of annual and perennial, glabrous herbs with creeping rhizomes. Plants

ALISMATALES

MONOCOTS

can grow terrestrially, in mud or submerged in fresh or brackish water with floating leaves. Roots sometimes bear tubers from which new plants can emerge. Leaves form a rosette at the tip of the rhizome with an open sheathing base and a linear flattened or rounded blade that has one to several veins. Sheaths often remain as a fibrous mantle around the rhizome. Inflorescences lack bracts and are composed of terminal spikes or spike-like racemes. The actinomorphic flowers are bisexual or unisexual, in the latter case usually with female flowers at the base, bisexual flowers in the middle and male flowers at the tip (or males entirely absent). One or six tepals are placed in one or two whorls or are (rarely) absent. Sessile stamens number one, four or six (or are absent); the anthers have two chambers that open with slits. The superior ovary is composed of one, three or six fused carpels that separate upon maturing. Stigmas are sessile or with a short style, rarely the style elongate and filiform in basal flowers (Triglochin scilloides). Fruits are achenes that are sometimes hooked or horned at the tip. Distribution: This family is found across the temperate Northern Hemisphere, in South America, southern Africa, New Guinea, Australia and New Zealand. Phylogeny and evolution: Juncaginaceae are dated to c. 82 million years, diversifying c. 52 million years ago. Australian species of Triglochin are now placed in the genus Cycnogeton. Lilaea scilloides has been merged with Triglochin, from which it differs only in its elongate styles. Tetroncium is sister to the other two genera. Genera and species: A family of three genera with 34 species: Cycnogeton (8), Tetroncium (1) and Triglochin (25). Uses: Rhizomes of Cycnogeton procerum and leaves of Triglochin maritimum are edible. Etymology: Juncago is derived from Latin juncus, a rush, and the suffix -ago meaning ‘a sort of’. Juncago is a later synonym of Triglochin.

72. MAUNDIACEAE Maund’s-arrowgrass family

This family consists of perennial, aquatic, glabrous herbs with 5 mm thick rhizomes and emergent tufts of leaves along their lengths. Leaves are triangular in cross-section and up to 80 cm long, with open sheaths at the base. The sheaths remain when the leaves wither, forming a fibrous mantle around the rhizome. Inflorescences are terminal spikes to 10 cm long, without bracts. Flowers are bisexual, actinomorphic, with two to four, scale-like, fleshy tepals. The two to eight stamens are short and the anthers unilocular, opening with longitudinal slits. The superior ovary is composed of three or four fused carpels that separate upon maturing, each with a spreading beak. Stigmas are sessile and elongate. Fruits are beaked achenes. Maundia triglochinoides, collected by S. T. Blake (20053) in Queensland, Australia (Herbarium Kew)

Distribution: This species occurs in northeastern Australia (coastal New South Wales into southern Queensland), in swamps and shallow fresh water on heavy clay soils. It is listed as vulnerable, highly likely to become endangered, due to draining and filling of swamps and lowering of water tables in the areas where it occurs. Phylogeny and evolution: Even though morphologically similar to Juncaginaceae (and traditionally placed there), Maundia is sister to a clade that unites Potamogetonaceae, Juncaginaceae and the seagrass families (Cymodoceaceae, Posidoniaceae, Ruppiaceae and Zosteraceae). It may be that in the future all of these families can be merged into an expanded Juncaginaceae, but for the time being a conservative approach places Maundia in its own family. Genera and species: This family is composed of the single species Maundia triglochinoides. Etymology: Maundia was named to commemorate Melbourne medical physician John Maund (1823–1858).

73. ZOSTERACEAE Eelgrass family

[72]

This family is composed of perennial, marine, submerged plants. The creeping, branched rhizomes grow in sandy or muddy substrates on the sea floor and in intertidal zones or on submerged rocks. Their leaves are alternate, in one plane (distichous), with an open, sheathing base and linear blade with parallel venation. Leaves lack stomata. Flowers are unisexual or bisexual, arranged on either side of a stem (when unisexual, male and female flowers

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ALISMATALES alternating), with a spadix that is usually enveloped in a modified leaf sheath (spathe). Male flowers consist of only a single stamen. The anther is bilocular with a ridge-like connective. Pollen is filiform. Female flowers are composed of a single ovary with a short style bearing two long stigmas. Pollination takes place under water, the flowers not emergent. The fruit is an achene. Distribution: Zosteraceae occur in temperate and subtropical oceans: North Atlantic, Mediterranean, Pacific, Chilean coast, Indian Ocean around southern and eastern Africa and cool waters around Australia and New Zealand.

MONOCOTS

Phylogeny and evolution: Zosteraceae diversified c. 30 million years ago. There are no known fossils, the fossil genus Archeozostera being misinterpreted. The family is closely related to Potamogetonaceae. A clone of Zostera marina in the Baltic Sea has been estimated to be at least a thousand years old. Genera and species: This family has two genera and 22 species: Phyllospadix (6) and Zostera (16). Uses: Eelgrass, Zostera marina, has been used as packing material in the past. The large sea meadows of Zostera are important breeding

grounds for numerous marine animals, including commercially important fish and shrimp species. Etymology: The name is derived from a Greek belt or girdle called ζωστήρ (zoster), which was mostly worn by men in ancient Greece (from c. 700 to 500 BC). This of course is in reference to the long belt-like leaves of these plants.

74. POTAMOGETONACEAE Pondweed family

Phyllospadix scouleri, Monterey Bay Aquarium, California, USA [73]

These aquatic plants are usually perennials that have a few roots at the basal nodes of the stems. Plants can be free-floating or rooted in substrate. Stems are slender, often dimorphic, the lower ones resembling rhizomes, and can bear tubers, the upper ones erect and floating with the tips developing into winter buds (turions) in many species. Leaves are floating or submerged, alternate or opposite, sometimes in false whorls, sessile Potamogeton tricarinatus, Oodnadatta, South Australia [74]

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Zannichellia palustris, Germany (CF) [74]

ALISMATALES

MONOCOTS

or petiolate, usually with a pronounced ligule that forms a tube-like open sheath around the stem, which may be completely free from the leaf. Leaves can have one vein when linear, but in many species the leaf blades are wider and the veins several, parallel and often connected with regular crossveins. Inflorescences are borne in the leaf axils or terminate a stem. They are long-stalked and often emergent or sessile (in Althenia, Lepilaena and Zannichellia). They can have two to several flowers or be composed of many flowers in a head or spike. When flowers are bisexual, two to four tepals occur in one whorl and surround the usually four stamens, the filaments fused with the sepals and bilocular anthers opening by slits. In species with unisexual flowers, the perianth of the male flowers can be absent or minute and trilobed, with a single stamen and a one to 12-locular anther opening by slits. In perfect flowers, the superior ovary is usually composed of four distinct carpels with a short

style, but in taxa with separate female flowers petals are a small cup-like sheath or three separate segments enclosing the superior ovary with one to eight free carpels. The fruit is usually formed by individual carpels becoming small drupes. Distribution: The family occurs globally but is absent from the great deserts. Phylogeny and evolution: The earliest fossil records of Potamogetonaceae date from the Palaeocene and become more common during the Eocene with a diversification around 25 million years ago. In previous classifications, Potamogeton was placed in a broad assembly of related aquatic plants such as Halodule, Najas, Ruppia and the seagrass families. They are indeed closely related and could be merged into a single family if Juncaginaceae (the name that has priority) is also included. Zosteraceae appear to be closest to Potamogetonaceae, as these families share similar adaptations to

aquatic habitats. Because of their extreme reduction in vegetative and floral morphology, Zannichellia and associated genera Althenia and Lepilaena were previously placed in a separate family Zannichelliaceae. They share coiled cotyledons, which is a good synapomorphy for the family, but is difficult to see with the naked eye. Genera and species: Potamogetonaceae include six genera with 110 species: Althenia (2), Groenlandia (1), Lepilaena (6), Potamogeton (89), Stuckenia (6) and Zannichellia (6). Uses: Apart from occasional use as ornamentals, the family has few uses. It is an important food source for waterfowl and aquatic animals. Etymology: Potamogeton is derived from the Greek ποταμός (potamos), river, and γειτον (geiton), a neighbour.

Potamogeton crispus, Surrey, England, UK [74]

Posidonia coriacea, Perth, Western Australia [75]

Potamogeton illinoensis, Cordley Lake, Michigan, USA [74]

Posidonia australis, Western Australia (KD) [75]

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ALISMATALES

MONOCOTS

Ruppia megacarpa, South Australia [76]

Ruppia megacarpa, habit, South Australia [76]

Amphibolis antarctica, Adelaide, South Australia [77]

75. POSIDONIACEAE

Genera and species: The family has a single genus, Posidonia, with nine species.

or appearing opposite, with a sheath surrounding the stem and a distinct linear, single-veined blade. The blade is apically serrate, entire towards the base. Flowers are axillary, singular or in few-flowered heads, sometimes in terminal spikes, the peduncles elongating to place the flowers near the water surface at anthesis. Flowers are bisexual, without petals, the two stamens sessile and the anthers opening by slits. The superior ovary is composed of usually four free carpels (rarely two or up to 16), each with a style and a sessile, peltate stigma. Fruits are stalked or sessiles drupes.

Tapeweed family

Washed ashore: Most people will encounter these plants washed ashore. Fragments of these plants break off and the waves work them into perfect globes of fibrous material, often found along Mediterranean or Australian shores.

These marine plants are large submerged herbs with creeping rhizomes covered by remnants of old leaf sheaths. Leaves are alternate, in one plane (distichous) with a sheathing base and distinct blade. The blade is linear with three or more vascular bundles and lacks stomata. The terminal inflorescence is a compound spike-like bracteate raceme on a long flattened peduncle. The bisexual flowers lack petals. The three stamens have sessile anthers that open by slits and release filiform pollen. The superior ovary is composed of a single carpel with an ornate stigma. The fruit is a spongy achene. Distribution: This family occurs in the Mediterranean and temperate oceans of southern and western Australia. Phylogeny and evolution: Clones of Posidonia oceanica in the Mediterranean can be several kilometres across and have been estimated to be dozens of millennia old. 130

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Etymology: Posidonia is named for the Greek god, Ποσειδων (Poseidon), one of the 12 Olympian deities of Greek mythology. His realm is the ocean, and this marine genus is thus appropriately named.

76. RUPPIACEAE Tasselweed family

Distribution: This family grows in ponds, saltmarshes and shallow seas worldwide with patchy distributions on all continents. Phylogeny and evolution: The earliest fossils of Ruppiaceae date from the Palaeocene. A dubious fossil of Limnocarpus from the middle Eocene of Denmark may be a Ruppia because of similarities in the endocarp. The family is closely related to and doubtfully distinct from Cymodoceaceae.

This family is composed of usually annual, submerged, aquatic herbs, found mostly in fresh and brackish water. Roots are few and fibrous. Stems are slender, often dimorphic, with the lower parts rhizomatous and the upper part erect and leafy, but not forming winter buds. Leaves are alternate

Genera and species: This family includes the single genus Ruppia with eight species. Etymology: Ruppia was named to commemorate German botanist Heinrich Bernhard Rupp (1688–1719).

PETROSAVIALES

MONOCOTS

77. CYMODOCEACEAE Turtle-grass family

This is a family composed of perennial marine herbs with creeping, branched rhizomes and often erect leafy branches. Leaves are alternate, in one plane (distichous) with a sheathing base and distinct blade. A thin ligule is present between the sheath and blade. The sheath leaves a scar on the stem after being shed. Blades are linear, flat or rounded, and lack stomata. Flowers are

solitary or arranged in cymes. Unisexual flowers lack petals but are enclosed by leaflike bracts. Male flowers are subsessile or with a pedicel and composed of two stamens. Female flowers are composed of two free ovaries, each bearing a long, unbranched or branched, filiform style. Usually only one carpel develops into an indehiscent fruit that in some genera germinates on the mother plant.

from fossils of the Upper Cretaceous of the Netherlands (Thalassocharis) and the Mid Eocene of Florida (Thalassodendron). The crown clade is estimated to have originated 100 million years ago.

Distribution: Cymodoceaceae occur in tropical and warm temperate seas worldwide, particularly around Australia.

Uses: In places where large marine meadows occur, this family is important in providing breeding and feeding grounds for numerous animals including economically important crustaceans and fish.

Phylogeny and evolution: Cymodoceaceae are closely related to Ruppiaceae and Potamogetonaceae, refuting the hypothesis that all seagrasses have an exclusive common ancestor. Cymodocea is possibly not monophyletic. The family is known

Genera and species: This family has five genera and 17 species: Amphibolis (2), Cymodocea (4), Halodule (6), Syringodium (2) and Thalassodendron (3).

Etymology: Cymodocea (Κυμόδοκεα) was one of the nymphs in Virgil’s Aeneid, the daughter of Nereus and receiver of waves.

PETROSAVIALES This is an order with little diversification, consisting of only one family Petrosaviaceae. Age estimates vary, but typically are around 100 million years old.

78. PETROSAVIACEAE Oze-so family

This family is composed of pale yellow, mycoheterotropic (Petrosavia) and perennial green (Japonolirion) herbs. They have slender scaly rhizomes and scale-like or linear, alternate or spirally arranged leaves.

Inf lorescences are terminal corymbs or racemes, usually with more than ten flowers. Actinomorphic bisexual flowers arise from axils of small bracts placed on a pedicel, often subtended by a bracteole or bracteole absent (Japonolirion). Six petals are persistent and free or fused at the base, the inner three larger than the outer. Six stamens are fused to the petal segments, and anthers are ovate and dorsifixed or basifixed. The superior or half inferior ovary is composed of three nearly free carpels, fused at the base and free at least in the top half. The ovary is surrounded by septal nectaries and topped by three short styles. The fruit is a capsule composed of three follicles with several elliptic seeds, winged in Petrosavia.

Japonolirion osense, Royal Botanic Gardens, Kew, UK (RW) [78]

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PETROSAVIALES

MONOCOTS

Distribution: Petrosavia occurs in eastern China, Japan, Taiwan, Southeast Asia, Malaysia and Indonesia, often at high elevations. Japonolirion osense is endemic to serpentine swamps in montane central Honshu and Hokkaido. Phylogeny and evolution: Petrosaviaceae are sister to the rest of monocots except Acorales and Alismatales; they are placed

in Petrosaviales. Japonolirion was placed in its own family as well, but molecular studies have shown it to be closely related to Petrosavia, and the families were merged. The crown group of Petrosaviaceae has been dated to c. 123 million years, although other estimates are closer to 100 million years. Petrosavia was previously associated with Triuridaceae, based on their free carpels and mycoheterotrophic habit. They have also

been placed close to or within Melanthiaceae or Nartheciaceae in the past. Genera and species: There are two genera with four species: Japonolirion (1) and Petrosavia (3). Etymology: Petrosavia is named in honour of Italian botanist Pietro Savi (1811–1871), prefect of the Pisa Botanic Garden.

DIOSCOREALES Families 79 to 81 comprise the order Dioscoreales, a clade that is estimated to have diverged c. 123 million years ago. They all have vascular bundles in rings. Glandular hairs in flowers or inflorescences and winged ovaries are also common.

79. NARTHECIACEAE Bog asphodel family

A family of perennial herbs, these plants have creeping rhizomes tipped with (unifacial)

Aletris pauciflora, Yunnan, China [79]

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linear, distichously or spirally arranged leaves. The flowering stem also often has some smaller linear alternate leaves that clasp the base of the stem. Actinomorphic flowers are arranged in terminal racemes, spikes or corymbs subtended by linear or lanceolate bracts. Each flower has a single linear bracteole attached to the pedicel. The six petals are basally fused and persistent in fruit, with the stamens inserted at the base of the petals. Filaments are thread-like and densely hairy in Narthecium, glabrous in the other genera. Anthers are linear and dorsifixed or basifixed. The superior or half inferior

Aletris pauciflora, Yunnan, China [79]

ovary is composed of three fused carpels with a single columnar style and a capitate stigma. The fruit is a loculicidal capsule that splits in three when ripe, exposing many, small, linear or oblong seeds. Distribution: This family occurs patchily across the Northern Hemisphere (California, eastern and southern USA), Guiana Highlands, Western Europe, Caucasus, China, Korea, Japan, Philippines, Borneo and Sumatra. Narthecium ossifragum and some Aletris species form large populations under suitable conditions.

Narthecium ossifragum, Lake District, England, UK [79]

DIOSCOREALES

MONOCOTS

Phylogeny and evolution: Due to their flowers lacking distinctive characters, they were previously associated with a number of other monocot families, including Tofieldiaceae, Petrosaviaceae, Melanthiaceae and Liliaceae. Molecular studies placed this family as sister to the rest of Dioscoreales. Metanarthecium luteoviride may be sister to the rest of the family, and Aletris, with its spirally arranged leaves, is sister to the remaining genera. The crown group diverged c. 76 million years ago. Genera and species: This family has five genera with 35 species: Aletris (24), Lophiola (1), Metanarthecium (1), Narthecium (7) and Nietneria (2).

Gymnosiphon breviflorus, Costa Rica (PM) [80]

Burmannia bicolor, Colombia (MF) [80]

Uses: The bright orange fruits of Narthecium ossifragum have been used as a dye in the Shetland Islands. Unicorn root (Aletris spp.) contains a diosgenin (an oestrogen mimic) that was an important component of Lydia Pinkham’s women’s tonic, a concoction used in the 19th century to relieve menopausal and menstrual pains. Etymology: A narthecium is a Roman perfume box, which in turn is derived from Greek νάρθεξ (narthex), a giant fennel with enclosing scented leaves, a name used by Theophrastos for Ferula communis (Apiaceae). Narthex is now used as a term in architecture for the entrance hall of Byzantine and early Christian churches.

80. BURMANNIACEAE Bluethreads family

This family consists of annual and perennial herbs that are autotrophic, partially heterotropic (but still green) or more commonly fully mycoheterotropic and then differently coloured (blue, purple or white),

Afrothismia korupensis, Cameroon (CD) [80]

Hexapterella gentianoides, Guyana (PM) [80]

Thismia saulensis, French Guiana (PM) [80]

Gymnosiphon usambaricus, Taita Hills, Kenya [80]

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DIOSCOREALES and lacking chlorophyll. They usually have rhizomes that are densely covered with overlapping scale-like leaves and filiform or coral-like roots. Tubers are sometimes also formed. Leaves are alternate, lacking petioles, simple, usually small and scalelike in fully mycoheterotrophic species, or larger, green and forming a basal rosette in autotrophic or partially heterotrophic species. Inflorescences are terminal, bracteate, one to several-flowered cymes that can be contracted into a head or lax and then usually forking. Bisexual flowers are usually actinomorphic, but zygomorphic in Thismieae. The perianth is composed of a tubular basal part and six tepals arranged in two whorls. The floral tube is usually persistent in fruit and often provided with longitudinal ribs or wings, confluent with the frequently three-winged ovary. Three or six stamens are erect or pendulous with bithecal introrse anthers and a widened connective. The three-branched style has a stigma terminating each branch. The inferior ovary is unilocular with septal nectaries. The fruit is a three-winged capsule that splits longitudinally or transversely by slits or irregularly opening due to a decaying fruit wall. Fruits contain numerous, fine seeds.

MONOCOTS

Crown group Burmannieae are dated to c. 75 million years, with Thismieae dated to c. 68 million years. Genera and species: This is a family of 17 genera and 166 species: Burmannieae – Apteria (1), Burmannia (57), Campylosiphon (2), Cymbocarpa (2), Dictyostega (1), Gymnosiphon (30), Hexapterella (2), Marthella (1) and Miersiella (1); Thismieae – Afrothismia (12), Desmogymnosiphon (1), Geomitra (1), Haplothismia (1), Oxygyne (4), Scaphiophora (2), Thismia (47) and Tiputinia (1). Etymology: Burmannia commemorates the Dutch botanist Johannes Burman (Johannus Burmannius, 1707–1780), a contemporary of Carolus Linnaeus. Burman introduced Linnaeus to George Clifford, resulting in a close collaboration between the two. Burman was a specialist on the flora of Sri Lanka, Ambon and the Cape.

81. DIOSCOREACEAE Yam family

Distribution: Pantropical, extending north to the southeastern USA and Japan and south into temperate eastern Australia and northern New Zealand. Phylogeny and evolution: In some phylogenetic analyses Burmanniaceae are sister to Dioscoreaceae, whereas in others Thismieae are closer to Tacca rather than to Burmannieae. Support for these clades is weak in all analyses. They share morphological characters. Tacca can therefore easily be absorbed into either family, or the two families may be combined in the future. This depends on the data obtained by further studies on Dioscoreales. The alternative is to maintain Burmanniaceae but move Thismieae to Dioscoreaceae. In that case there are few characters that separate the two and they could just as well be united.

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This is a family of herbaceous and woody vines and erect perennial herbs with rhizomes or root tubers. Stems are twining or not, sometimes armed with prickles. Petiolate leaves can be alternate, opposite or wholed, with or without stipules. The petiole is usually sheathing at base and often twining (Dioscorea). Leaf axils sometimes bear bulbils. Blades are simple or palmately compound or palmately lobed with palmate venation, basally with three to 13 main veins or pinnate (in some Tacca species) with the secondary venation reticulate. Inflorescences are usually axillary panicles, racemes, or spikes, sometimes reduced to a single flower, in Tacca an umbel with two

whorls of broad or elongate involucral bracts. Flowers are actinomorphic, usually unisexual (Dioscorea) or bisexual (Stenomeris, Tacca, Trichopus). Male flowers have six tepals in two whorls, fused basally or free. The six stamens sometimes have the inner whorl sterile and staminodial or completely absent, the filaments free, fused to tepals or forming a staminodial column. The connective is often broad or appendiculate. Female flowers are similar to the males, with six, three or no staminodes and an inferior, trilocular, often winged ovary, topped by three free styles, the stigmas petal-like in Tacca. The fruit is a capsule, berry or samara, and seeds often have a membranous wing. Distribution: This is a pantropical family extending into temperate North America, Europe, Asia and Australia. Phylogeny and evolution: On morphological grounds, Trichopodaceae and Taccaceae were merged with Dioscoreaceae, and the genus Dioscorea was taken in its broad sense to include Borderea, Epipetrum, Rajania, Tamus and Testudinaria. Most genera share the winged fruits (but not the former berryfruited genus Tamus), the wings formed from the corolla. They share this character with Burmanniaceae, a family close to (or part of) Dioscoreaceae. In some analyses Tacca appears to be more closely related to Thismieae (Burmanniaceae) rather than to Dioscorea. In other analyses Burmanniaceae are sister to the rest, but support is low. It remains to be seen if Dioscoreaceae will need to be expanded in the future. Tacca diverged from the rest of Dioscoreaceae c. 35 million years ago. Genera and species: A family of four genera and 641 species: Dioscorea (622), Stenomeris (2), Tacca (15) and Trichopus (2). Uses: Tubers of several species of Dioscorea are cultivated as yams. Different species have been brought into cultivation independently in different tropical regions. It has been suggested that yams were first domesticated in West Africa c. 11,000 years ago, but other

DIOSCOREALES

MONOCOTS

Dioscorea communis, male flowers, Box Hill, England, UK [81]

Dioscorea hastata, Western Australia [81]

Dioscorea polystachya, aerial tubers, Helsinki Botanical Garden, Finland [81]

Trichopus zeylanicus by M. Smith from Curtis’s Botanical Magazine vol. 120: plate 7350, 1 (1894)

Tacca palmata, Royal Botanic Garden Edinburgh, Scotland, UK [81]

Tacca integrifolia , Singapore (WA) [81]

species were domesticated about the same time in southern China. Dioscorea alata and D. esculenta are cultigens, not known from the wild but originating in Asia. They are now widely cultivated throughout the tropics where they easily naturalise. Other species cultivated as crops include African D. cayennensis and D. dumetorum, Asian D. bulbifera, D. japonica, D. oppositifolia, D. pentaphylla and D. polystachya, and American D. trifida.

In addition, the large quantities of steroidal saponins found in tubers are used as a fish or arrow poison and for washing clothes and tanning. This has now attracted the attention of the pharmaceutical industry for the synthesis of corticosteroids and hormones. The fruits of Trichopus zeylanicus are used in India to make a ginseng-like rejuvenating drink. Tubers of particular cultivars of Tacca leontopetaloides are a staple food in Pacific and Indian Ocean

islands. Bat-flower, Tacca integrifolia, and elephant foot, Dioscorea elephantipes, are occasionally used as houseplants or tropical garden ornamentals.

[81]

Etymology: Dioscorea is named for the ancient Greek physician, pharmacologist and botanist Pedianus Dioscorides (Διόσκορίδες, c. 40–90 AD), author of De Materia Medica, a medical encyclopedia.

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PANDANALES

MONOCOTS

PANDANALES Families 82 to 86 make up the order Pandanales. This clade diverged c. 114 million years ago and can be recognised by its mostly three-ranked leaves (except for mycoheterotrophic Triuridaceae).

Sciaphila albescens, Guyana (PM) [82]

Triuris hexophthalma, male, Guyana (PM) [82]

Triuris hexophthalma, female, Guyana (PM) [82]

82. TRIURIDACEAE

usually unisexual flowers are actinomorphic or zygomorphic, with three to ten tepals in a single series that is usually fused at the base and sometimes has appendages at the apex. The two to six stamens are inserted at the base of the receptacle and have anthers with two or four thecae that mostly open by transverse slits. The connectives are often reduced into long subulate appendages. Female flowers have six to numerous free carpels with a terminal to subbasal style. Fruits are follicles or achenes opening by slits. In Lacandonia the carpels surround the stamens, a rare situation among angiosperms.

anatomy, Tr iu r idaceae have always been difficult to place among monocots. Molecular evidence now supports an association with Pandanales. Molecular age estimates date this family to c. 90 million years ago, which agrees with similarly dated Cretaceous fossils found in New Jersey. Sciaphila may be paraphyletic, based on molecular analyses.

Threetails family

These mycoheterotrophic, perennial, monoecious and dioecious herbs lack chlorophyll and are usually white, yellow, reddish or purple. Stems are erect, growing from a creeping or erect rhizome covered in scale-like leaves. Above-ground leaves are also strongly reduced, alternate and scalelike. The inflorescence is a few to many flowered, bracteate raceme or subcorymb. The 136

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Distribution: This is a pantropical family, but sparse and patchy in Africa and mainland tropical Asia. Phylogeny and evolution: Because of their mycoheterotrophic habit and reduced

Genera and species: This family has nine genera and c. 55 species: Kihansia (1), Kupea (2), Lacandonia (2), Peltophyllum (2), Sciaphila (37), Seychellaria (4), Soridium (1), Triuridopsis (2) and Triuris (4). Etymology: Triuris is composed of the Greek words τρία (tria), three and ουρά (oura), a tail, in reference to the flowers of that genus that have three long-tipped tepals.

PANDANALES

MONOCOTS

83. VELLOZIACEAE Baboon-tail family

This family includes perennial herbs that are sometimes shrubby with fibrous woody stems without secondary growth. The stems are simple or bifurcating and are covered with persistent leaf sheaths. Roots alternate with the leaves and grow down through the leaf sheaths. The leaves are arranged in threes (tristichous) that can spiral around the stem (spirotristichous) and are often clustered at the tips of branches. Blades are needle-shaped (acerose) or flat and linear, often V-shaped and sheathing at the base, and can be persistent or deciduous from the base along a straight line. What appear to be terminal inflorescences become lateral because of the growth of the axis, with a scape and one to many flowers, a raceme in the latter case, or

Vellozia sp., near Mucugê, Bahía, Brazil [83]

(in Acanthochlamys) a compound head on a scape, surrounded by three leaf-like bracts, each flower subtended by three bractlets. Flowers are usually bisexual (unisexual in Barbaceniopsis), actinomorphic and usually brightly coloured. The six tepals are all similar and in two whorls of three, all brightly coloured and long-persisting, fused at the base in most genera, but fused into a tube in Acanthochlamys. Stamens are six or numerous (but then in six bundles) and have filaments that are free or fused with the petals, sometimes with basal appendages. Anthers are basifixed or dorsifixed, the two thecae opening by longitudinal slits. The trilocular, inferior or half inferior ovary is topped with a slender style and three stigmas. The fruit is a capsule that opens by slits or pores.

have been made, and some placements are still uncertain, which is why seven genera are tentatively accepted here. It is certain that Acanthochlamys is sister to Vellozioideae, and since there are many anatomical differences, recognition at subfamilial level (as Acanthochlamydoideae) seems appropriate. The crown group of this family dates back to c. 115 million years. Velloziaceae currently have a Gondwanan distribution, and the age of the lineage indicates that this could be due to vicariance, although long-distance dispersal cannot be excluded.

Distribution: This family is widespread across South America, particularly Brazil, Sub-Saharan Africa, Madagascar and Yemen, with an isolated genus in China.

Uses: Fibre of Xerophyta equisetoides has some local traditional uses in South Africa. Some species such as Talbotia elegans are valuable ornamental plants, although rarely offered in the commercial trade.

Genera and species: This family has seven genera with c. 285 species: Acanthochlamys (1), Barbacenia (108), Barbaceniopsis (4), Nanuza (3), Talbotia (1), Vellozia (126) and Xerophyta (42).

Phylogeny and evolution: There is still disagreement concerning generic delimitation in this family. A consensus has developed to recognise five genera, but not all combinations

Et ymology: Vellozia is named to commemorate Brazilian botanist José Mariano da Conceição Vellozo (1742–1811).

Acanthochlamys bracteata, Yunnan, China (HS) [83]

Talbotia elegans, Helsinki Botanical Garden, Finland [83]

Xerophyta eglandulosa, Isalo National Park, Madagascar (CD) [83]

Barbacenia sp., near Mucugê, Bahía, Brazil [83]

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PANDANALES

84. STEMONACEAE Baibu family

This is a family of twining and erect, sometimes creeping and shrubby perennial herbs with creeping rhizomes or tuberous roots. Leaves are simple, without stipules, and are alternate, opposite or whorled, usually with a basally sheathing petiole. Blades are ovate with an entire margin, and venation is palmate from the base or arching pinnate with a strongly developed midvein, the primary veins connected by transverse parallel veinlets. Inflorescences are axillary and consist of a single flower or lax, few-flowered cymes,

MONOCOTS

sometimes in false umbels or (compound) racemes. Flowers are actinomorphic and usually bisexual (functionally unisexual and somewhat dimorphic in Pentastemona and Stichoneuron). The four or five tepals are free or fused at the base. The stamens are opposite the tepals with filaments usually fused to them or to each other (Pentastemona). Anthers open by longitudinal slits and often have thecae that protrude into sterile appendages that can be fused at their tips, the connective sometimes with a petal-like appendage. The superior or (semi-) inferior ovary has a single locule topped by a sessile one- to four-lobed stigma. Fruits are berries (Pentastemona) or two- or three-valved capsules that usually open to show seeds that dangle on funicles and are provided with fleshy hairs (in Stemona). They are distributed by ants. Distribution: The family is distributed disjunctly in temperate southern USA, and (sub)tropical Asia: Sri Lanka, Southeast Asia, Malesia, southern Japan, New Guinea and northern Australia.

Stemona tuberosa, Kunming Botanical Gardens, China [84]

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Phylogeny and evolution: Because of the climbing habit of some Stemonaceae and their reticulately veined leaves, this family was traditionally associated with Dioscoreaceae. Molecular evidence shows, however, that they are more closely related to Pandanaceae and Cyclanthaceae (Pandanales), with which they share parietal placentation and absence of a style. Pentastemonaceae are embedded in Stemonaceae. They diverged from Pandanaceae/Cyclanthaceae c. 100 million years ago. Genera and species: Stemonaceae have four genera with 37 species: Croomia (6), Pentastemona (2), Stemona (24) and Stichoneuron (5). Uses: Stemona tuberosa is used in traditional Chinese medicine. Etymology: Stemona is derived from Greek στημών (stemon), a stamen or thread, in reference to the conspicuously elongate thecae of some species.

Croomia japonica, Zhejiang, China (CD) [84]

PANDANALES

MONOCOTS

Carludovica palmata, fruit, Royal Botanic Gardens, Kew, UK [85]

Carludovica drudei, Royal Cyclanthus bipartitus, Trésor Voluntary Botanic Gardens, Kew, UK [85] Reserve, French Guiana (CD) [85]

85. CYCLANTHACEAE Panama hat family

Cyclanthaceae consist of perennial, terrestrial and epiphytic, palm-like herbs and vines, with short-creeping and long, slender and climbing, often somewhat woody stems with only primary growth. Leaves are alternate along the rhizome, either spirally or in one plane (distichous), and have sheathing petioles in most species. Blades are usually split into two parts (bifid), sometimes entire or palmately divided. Inflorescences are axillary or terminal and composed of a stalked spadix subtended by two to 11 leaf-like or petal-like spathes that initially envelop the inflorescence. Unisexual f lowers are densely crowded in spirally arranged groups, each consisting of a female flower surrounded by four male flowers, or (in Cyclanthus) in circles around the spadix, the male and female whorls alternating. Male flowers usually surrounded by perianth lobes,

Asplundia rigida, Guadeloupe [85]

in one or two whorls or lacking; in Cyclanthus male flowers are linear rows of stamens. Stamens are usually numerous, with basifixed anthers and filaments that are usually basally fused. Female flowers are free or partially fused with each other. The four tepals are free or fused and often enlarged in fruit. The superior or semi-inferior ovary is surrounded by four staminodes that are elongate and filiform, protruding from the flowers. The tetracarpellate ovary is unilocular and tipped with four stigmas sometimes placed on styles. In Cyclanthus, female flowers are not discrete but rather fused into circles consisting of a double row of pistils, the locules fused into a single ovary chamber, surrounded by a row of reduced tepals and staminodes on either side. Fruits are usually fused into a fleshy syncarp or free. In Cyclanthus the fruit is a dry, cone-like structure with hollow rings filled with seeds. Distribution: This family occurs only in tropical America. Phylogeny and evolution: The family diverged from their relatives in Pandanales c. 77 million years ago. Fossils from the Eocene in Europe have been identified, demonstrating that the family was once present in the Old World. Cyclanthus is usually placed in its

Asplundia insignis, Guadeloupe [85]

own subfamily on anatomical grounds. Genera and species: This family has 12 genera with c. 230 species: Asplundia (c. 100), Carludovica (4), Chorigyne (7), Cyclanthus (2), Diantho-veus (1), Dicranopygium (54), Evodianthus (1), Ludovia (3), Schultesiophytum (1), Sphaera-denia (52), Stelestylis (4) and Thoracocarpus (1). Uses: In several countries in Central and South America, but mostly in Ecuador, the fibre of Carludovica palmata, called toquilla straw, is woven into hats, baskets and mats, and leaves of several other species are locally collected for roof thatching. Hats were imported to Panama for the foreign Canal workers, who gave the name ‘Panama hats’ to these distinctive, flexible straw hats, even though they did not originate in Panama. Young inf lorescences and fr uits of Asplundia, Carludovica and tucuso (Evodianthus funifer) are sometimes eaten by native peoples. Cyclanthus bipartitus and Carludovica palmata are sometimes grown as garden ornamentals in the tropics. Etymology: Cyclanthus is derived from Greek κύκλος (kyklos), circle and άνθος (anthos), flower, in reference to the disc-shaped inflorescence parts.

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PANDANALES

MONOCOTS

f lowers cannot be distinguished. Male flowers have two to numerous, spicately or umbellately aggregated stamens. Anthers open by longitudinal slits. Female flowers have free to fused carpels with a single ovule per carpel and sessile stigmas, appressed to the apex of the carpel, or with a distinct style that becomes spine-like in fruit. Fruits are fibrous drupes or berries, often fused into larger structures that disintegrate when the fruit is ripe.

86. PANDANACEAE Screwpine family

This family of dioecious woody palm-like trees, shrubs and climbers without secondary growth often forms roots from the leaf axils, which may be fully functioning support, stilt or clasping roots, or early aborted and becoming spine-like. The bark is covered in leaf scars. Leaves are spirally arranged in three (spirotristichous) or four (Sararanga) ranks and sessile, lanceolate or linear, sheathing at the rounded to auriculate base, folded lengthwise and M-shaped in crosssection when mature. In most species, margins and midribs are spiny. The (usually) unisexual inflorescences are terminal or axillary spikes, panicles, false umbels or globose heads, usually subtended by variously coloured spathe-like bracts. They are usually erect at first but become pendent when mature. The unisexual flowers are sessile and densely crowded. They lack a perianth, and flowers are fused in Freycinetia, in which individual Pandanus tectorius female inflorescence, Réunion [86]

Distribution: This family is distributed across the Old World tropics from West Africa, Madagascar, the Mascarenes and the Seychelles to India, southern China, the Philippines, Australia, New Zealand and Polynesia. Phylogeny and evolution: The crown group of Pandanaceae started their diversification c. 51 million years ago. Fossil pollen of Pandaniditis has been found in the Late Cretaceous and Early Tertiary of North America but may instead belong to Araceae. Fossil fruits have usually been proven to belong to Nypa (Arecaceae). Fossils older than the Mid Cretaceous are not known. The biogeography of the family has been discussed in the context of the breakup of Gondwana, but this stretches the age of the group too far back, and their occurrence and diversification on recent oceanic volcanic islands may indicate frequent long-distance dispersal. The large genus Pandanus has been

Pandanus tectorius, male tree, Réunion [86]

divided on the basis of molecular study, but these genera are often difficult to distinguish because characters of female fertile material are needed to identify them. Genera and species: Pandanaceae have five genera and c. 770 species: Benstonea (c. 60), Freycinetia (c. 250), Martellidendron (6), Pandanus (c. 450) and Sararanga (2). Uses: Pandan leaves, Pandanus amaryllifolius and P. tectorius to a lesser extent, are used as a spice in Southeast Asian cuisine, especially in rice and curry dishes or mixed with coconut milk. Fruit pulp of kuansu or buah merah, Pandanus conoideus, is economically important in Papua, and c. 30 cultivars are grown in Indonesia. Seeds of P. odoratus (synonym P. dubius) can be eaten raw. Fruits of the thatch screwpine, P. tectorius, are eaten raw or cooked in Micronesia, where they are an important food source. Pollen is fragrant and used for perfume and to flavour drinks. Kiekie, Freycinetia banksii, has sweet fruits and succulent inflorescence bracts that were considered a delicacy by the Maori of New Zealand. Freycinetia arborea, Pandanus tectorius and P. utilis are used for thatch fibre, basketry, weaving, plaiting and rope. Etymology: Pandanus is derived from pandan, the Malay name for the cooking spice, P. amaryllifolius.

Pandanus multispicatus, female inflorescences, Mahé, Seychelles [86]

Freycinetia scandens, Royal Botanic Gardens, Kew, UK [86]

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Pandanus spiralis, female tree, Northern Territory, Australia [86]

LILIALES

MONOCOTS

LILIALES Families 87 to 96 comprise Liliales, a diverse order that includes many geophytes. They have well-defined non-septal nectaries and extrorse anthers. Liliales have been dated to c. 115 million years ago.

87. CAMPYNEMATACEAE Green-mountainlily family

fertilisation. Stamens are inserted at the base of the tepals, and anthers open by longitudinal slits. The trilocular ovary is inferior and bears free styles. Capsular fruits open by decay of the lateral walls or remain unopened.

88. CORSIACEAE Ghost-flower family

Distribution: This family is restricted to Tasmania and New Caledonia. Phylogeny and evolution: The two genera are united in having green tepals, an inferior ovary and free styles. Together with Corsiaceae they form a sister clade to all other Liliales. The genera diverged c. 73 million years ago.

A family of rhizomatous herbs, these perennials have one or several basally clustered flat, linear leaves that are sheathing at the base and often have three teeth at the leaf tip. Inflorescences are contracted panicles that resemble umbels on a bracteate peduncle. Flowers are actinomorphic, each subtended by bracts, and pedicels each bear a bracteole. The bisexual flowers are generally small and green. The six persistent tepals, sometimes bearing nectaries (Campynemanthe), enlarge after

Genera and species: This family has just two genera and four species: Campynema (1) and Campynemanthe (3). Etymology: Campynema is derived from Greek καμπυλός (kampylos), bent or curved and νήμα (nema), a thread.

This family of mycoheterotrophic, perennial herbs lacks chlorophyll. Shoots emerge from a creaping rhizome (or tuber) and are pale red, purple or salmon, but not green. Three to seven alternate leaves are sessile, clasping the stem, and have three to seven parallel veins. Bisexual, zygomorphic flowers are solitary, terminating the stem. The six tepals form two whorls, the three inner and two outer tepals are narrow and thread-like, filiform, lanceolate or somewhat ovate. The upper

Campynemanthe parva, New Caledonia (JM) [87]

Campynemanthe parva, New Caledonia (JM) [87]

Corsia ornata, New Guinea (TF) [88]

Arachnitis uniflora, Chile (PE) [88]

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LILIALES been placed in Burmanniaceae, but molecular evidence has shown that Corsia does not belong in Dioscoreales, but rather has a relationship to Liliales, but their exact position there has been variable and controversial. Arachnitis was placed close to Thismia in one study, and thus Corsiaceae in the traditional sense may be polyphyletic, but more recent phylogenetic studies place this genus together with Corsia in Liliales sister to Campynemataceae. No data are yet available for Corsiopsis.

89. MELANTHIACEAE

Distribution: This family is found in southern South America, the Falkland Islands, southern China, New Guinea, Melanesia and northern Australia (Queensland).

Genera and species: Corsiaceae have three genera and 27 species: Arachnitis (1), Corsia (25) and Corsiopsis (1).

Phylogeny and evolution: Due to the mycoheterotrophic nature of these plants, they are morphologically much reduced, and it has thus been difficult to infer relationships on the basis of morphological characters. They have

Etymology: Corsia was named to commemorate Marquis Bardo Corsi Salviati (1844–1907), who founded a scientifically important collection of plants in greenhouses on his estate near Florence, Italy.

This family of perennial herbs has erect and creeping rhizomes, bulbs and corms. Leaves are in basal rosettes, all along the stem (Veratrum), sometimes with large basal leaves and smaller cauline leaves, or in a whorl at the stem apex, with or without a petiole. They are sometimes sheathing at the base and can have parallel or reticulate venation. Inflorescences are usually racemes,

Toxicoscordion fremontii, Mt Tamalpais, California, USA [89]

Trillium erectum, North Carolina, USA [89]

Pseudotrillium rivale, Royal Botanic Gardens, Kew, UK [89]

Ypsilandra thibetica, private garden, Kingston upon Thames, Surrey, UK [89]

Paris quadrifolia, Warburg Nature Reserve, Bix Bottom, England, UK [89]

outer tepal is broadly ovate and spathe-like, upright with a basal callus or bent downward covering the flower, with two rows of wartlike structures inside. The six stamens have short filaments, and anthers are dorsifixed. The inferior ovary is tricarpelate and bears free or fused styles with free stigmas. The fruit is a capsule that splits into three or opens at the tip only, exposing the numerous dustlike seeds.

142

MONOCOTS

Christenhusz, Fay & Chase

Wake robin family

Xerophyllum tenax, Josephine Lake, Idaho, USA (CD) [89]

LILIALES

MONOCOTS

sometimes spikes, panicles or false umbels, or (in Paris, Pseudotrillium and Trillium) a single sessile or pedicellate flower in the centre of the leaf whorl. Bisexual, usually actinomorphic flowers (zygomorphic in Chionographis) usually have six tepals that are in two whorls, but in Paris can be up to 18, and sometimes only a single whorl of three is present. Free or basally fused tepals can be green and sepallike or variously coloured and petal-like. Usually six (but up to 24) stamens comprising two (to six) whorls, are persistent and have basifixed or dorsifixed anthers that open by longitudinal slits or valves. The superior (sometimes semi-inferior or inferior) ovary is composed of usually three, rarely up to ten, carpels that are fused for more than a third of their length, sometimes completely so, topped with free or fused styles. Fruits are usually dry capsules that open in threes, berry-like fruits that open like a fleshy capsule exposing seeds that sometimes have a bright red aril and fleshy berries that have many seeds. Distribution: Temperate and boreal Northern Hemisphere extending south into Central America and the Andes south to Peru and in Asia into the Himalayas and Taiwan. Phylogeny and evolution: The crown group of Melanthiaceae may be 54 to 42 million years old. Paridoideae separated c. 16 million years ago. Paris is sometimes subdivided, but recognising the genera Daiswa and Kinugasa renders Paris paraphyletic. Paris, Pseudotrillium and Trillium have in the past been segregated as Trilliaceae, but molecular phylogenetic studies have shown that this clade is closely related to Xerophyllum (i.e. embedded in Melanthiaceae). Genera and species: This family includes 17 genera and 173 species in two subfamilies: Melanthioideae – Amianthium (1), Anticlea (11), Chamaelirium (1), Chionographis (6), Helonias (1), Heloniopsis (6), Melanthium (1), Schoenocaulon (26), Stenanthium (3), Toxicoscordion (8), Veratrum (28), Ypsilandra (6) and Zigadenus (1); Paridoideae – Paris (27), Pseudotrillium (1), Trillium (44) and Xerophyllum (2).

Uses: Species of Anticlea, Helonias, Heloniopsis, Paris, Trillium and Veratrum are grown as unusual garden ornamentals, especially in woodland gardens. Some species of Veratrum have been used medicinally, but the alkaloids they contain are highly poisonous. Largest genome: Paris japonica has the largest genome of any organism found to date, only approached in size by the fern Tmesipteris obliqua (Psilotaceae). All members of Paridoideae have large genomes, and the increases in genome size between Xerophyllum (with a small genome) and Pseudotrillium, and between Pseudotrillium and the rest of Paridoideae, are among the largest known. Etymology: Melanthium is derived from Greek μέλας (melas), dark or black and άνθος (anthos), flower, in reference to the dark petal colour of this species.

90. PETERMANNIACEAE Petermann’s-vine family

style and a trilobed, wet stigma. The fruit is a berry with numerous seeds. Distribution: The family is restricted to the central part of eastern Australia (Queensland and New South Wales), roughly between Brisbane and Sydney, where it grows in temperate rainforests. Phylogeny and evolution: Fossil evidence indicates that the family was more widespread in Australian rainforests during the early Eocene. They previously were associated with Philesiaceae or Smilacaceae, and although morphologically there are many similarities, molecular studies have shown that Petermannia forms an independent lineage closer to Colchicaceae and Alstroemeriaceae. In earlier versions of APG it was included in Colchicaceae, but it is genetically and morphologically distinct from that family (e.g. ovary position, anther fixation etc.). Genera and species: This family consists of a single species, Petermannia cirrhosa. Etymology: Petermannia is named for German botanist Wilhelm Ludwig Petermann (1806–1855), who was director of the herbarium and botanical garden at Leipzig. Petermannia cirrhosa, New South Wales, Australia (JB) [90]

This family consists of perennial, woody vines with underground rhizomes and prickly stems, climbing with tendrils that are opposite the leaves. The alternate leaves have petioles and a simple, entire blade with a reticulate secondary venation and pinnateparallel primary venation. Inflorescences are terminal, opposite a leaf and cymose without bracts. The stalked bisexual flowers are actinomorphic and often pendulous. The six tepals comprise two whorls and have a single vein and nectaries at the base. The six stamens have distinct filiform filaments and basifixed anthers that open with longitudinal slits. The unilocular, inferior ovary is composed of three fused carpels and is topped with an elongate

Plants of the World

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LILIALES

MONOCOTS

Bomarea dulcis, Royal Botanic Gardens, Kew, UK [91]

Luzuriaga radicans, Royal Botanic Gardens, Kew, UK [91]

91. ALSTROEMERIACEAE Inca-lily family

This family includes erect or creeping, mostly perennial herbs and vines, the stems evergreen or not. They are usually terrestrial but sometimes grow epiphytically. Rhizomes usually form thick storage roots, except in the single annual species. Leaves are sessile, evenly spread along the stem or crowded at the tip. Veins are parallel or arching, sometimes with reticulate or parallel cross-venation (tessellate), and leaves mostly twisted at the

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Bomarea multiflora, Ecuador [91]

Alstroemeria aurea, Royal Botanic Gardens, Kew, UK [91]

base and the leaf blade becoming partly or totally inverted (resupinate). Inflorescences are terminal, umbel-like cymes with one to many flowers or one or more flowers in bracteate or axillary cincinni. Bracts can be leaf-like or reduced to scales, sometimes in a false whorl. The bisexual flowers are actinomorphic or zygomorphic. The six (rarely eight in Drymophila) free, petal-like tepals are in two rows that can be similar or different, variously marked and with nectaries at the base, the inner ones usually clawed. Six stamens are free with anthers (seemingly) basifixed, opening by longitudinal slits or terminal pores. The inferior ovary is formed from three fused carpels and is uni- or trilocular, topped by a filiform style. Capsular fruits are usually dry and splitting into threes, sometimes explosively, or a berry. Distribution: This family occurs in tropical and temperate Central and South America,

Greater Antilles, Falkland Islands, southeastern Australia, Tasmania and New Zealand. Phylogeny and evolution: Alstroemeriaceae are sister to Colchicaceae but easily distinguished from that family due to their inverted leaves. The two families diverged from other Liliales c. 58 million years ago. The crown group of Alstroemeriaceae is c. 48 million years old, although much older estimates also exist. Drymophila and Luzuriaga have long been of dubious placement. Previously placed in Liliaceae or Philesiaceae, they were sometimes placed in their own family, but because they are sister to Alstroemeriaceae sensu stricto and share many characters such as the twisted (resupinate) leaves APG included them there. Schickendantzia and Taltalia are embedded in Alstroemeria. Leontochir is part of Bomarea. Schickendantziella, sometimes placed here, is a genus of Amaryllidaceae.

LILIALES

MONOCOTS

Genera and species: This family has four genera and 253 species: Alstroemeria (125), Bomarea (122), Drymophila (2) and Luzuriaga (4). Uses: Chuño is the flour extracted from the roots of Alstroemeria ligtu. Bomarea edulis is cultivated for its edible tubers, and consumption of it is widespread across Latin America. Several other species of Alstroemeria and Bomarea also have edible tubers that are locally consumed in South America. Quilineja (Luzuriaga radicans) produces fibre for rope making. Many cultivars of Alstroemeria are grown for the cut-flower market and make good garden plants. Etymology: Alstroemeria was named to commemorate Swedish naturalist Baron Clas Alströmer (1736–1794), a student and friend of Carolus Linnaeus.

Colchicum autumnale, Pyrenees, France [92]

92. COLCHICACEAE Naked-ladies family

This family comprises perennial, erect and climbing herbs with underground corms, tubers and rhizomes; they rarely have slightly woody stems (Kuntheria). Simple, parallel-arched veined leaves are alternately placed along the stem and often in one plane (distichous), sometimes subopposed or verticillate. Blades are sessile, usually sheathing at base (sometimes amplexicaul

Tripladenia cunninghamii, Australian National Botanic Gardens, Canberra [92]

in Uvularia), and the apex can be simply acute or cirrhose with a climbing tip in vining species. Inflorescences are terminal racemes, cymes, umbels or heads, or the flowers are solitary in leaf axils. The bisexual (sometimes unisexual in Wurmbea) flowers are actinomorphic or slightly zygomorphic. The six (rarely seven to 12) tepals are all equal or somewhat unequal, all petal-like, free or partially fused and usually bear nectaries, often clasping the stamens at the base. The six stamens have dorsifixed anthers that open by longitudinal slits. The superior, trilocular ovary is composed of three fused or partially fused carpels, terminating in free or (partially) fused styles. The fruit is usually a septicidal or loculicidal capsule, rarely (in Disporum) a berry. Seeds are distributed by wind or ants. Distribution: Colchicaceae occur in temperate North America, Europe, North

Gloriosa superba, private garden, Kingston upon Thames, Surrey, UK [92]

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LILIALES

Disporum cantoniense, Royal Botanic Gardens, Kew, UK [92]

MONOCOTS

Wurmbea sp. nov. (Christenhusz 6421), Western Australia [92]

Colchicum hantamense, Royal Botanic Gardens, Kew, UK [92]

Africa, the Middle East to Central Asia and Pakistan, Yemen, tropical East Africa, southern Africa, temperate and tropical Asia, from Sakhalin and Japan south to Burma, Malaysia, Luzon and Java, Australia, Tasmania and New Zealand. The family is remarkably absent from South America. Phylogeny and evolution: The concept of Colchicaceae has varied much in the past, and formerly all species were placed in a broad Liliaceae. A number of genera from the former Uvulariaceae are now included. Also, the Old World members of the genus Disporum, formerly in Convallariaceae, are included here. The New World species of Disporum are now Prosartes (Liliaceae), a good example of parallel evolution. Disporopsis belongs to Asparagaceae. Littonia has been merged with Gloriosa,

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Uvularia perfoliata, Royal Botanic Gardens, Kew, UK [92]

Burchardia congesta, Mt Benia, Western Australia [92]

and Neodregea and Onixotis are part of the Wurmbea clade. Bulbocodium and Merendera are part of Colchicum s.l., and this is in turn embedded in Androcymbium. The result is that all are now treated in Colchicum. Two subfamilies are sometimes recognised, but these do not seem to be monophyletic in their current circumscription. The family diverged c. 64 million years ago. Genera and species: Colchicaceae include 15 genera and c. 285 species: Baeometra (1), Burchardia (6), Camptorrhiza (2), Colchicum (159), Disporum (20), Gloriosa (12), Hexacyrtis (1), Iphigenia (12), Kuntheria (1), Ornithoglossum (9), Sandersonia (1), Schelhammera (2), Tripladenia (1), Uvularia (5) and Wurmbea (c. 50). Uses: Due to the toxic alkaloids in most

species, they are not suitable for human or animal consumption. They cause losses to livestock, and accidental or intentional poisonings of humans have also been reported. Colchicine (obtained from wild or cultivated Colchicum) is used in medicine and phar macology and in botanical laboratories to induce polyploidy in plant cells by disrupting cell division. Several species are popular garden or indoor ornamentals, especially Colchicum (autumn crocus, meadow saffron or naked ladies), Gloriosa superba (flame lily) and Uvularia (bellwort), Disporum and Sandersonia aurantiaca (lantern lily). Etymology: Colchicum is named for the Colchis region along the eastern Black Sea in western Asia, probably equivalent to modernday Georgia.

LILIALES

MONOCOTS

93. PHILESIACEAE Chilean-bellflower family

This is a family of much branched, erect shrubs and vines with the stems growing from short woody (primary) rhizomes. Leaves are spirally arranged or placed in one plane (alternate and distichous) and are usually shortly petiolate and more or less sheathing at the base. The simple leaves have one or several parallel main veins with transverse or reticulate secondary veins. Terminal or axillary inflorescences are one- to three-clustered and formed on short-bracted peduncles. Bisexual flowers are actinomorphic and pendulous. Tepals are in two whorls of three, the outer whorl much shorter and more or less sepal-like in Philesia, similar in size to the inner ones in Lapageria. The inner tepals are large, free and overlap at the edges to form tubes, often with nectaries inside. The six stamens are free or fused basally. The nearly basifixed anthers open by longitudinal slits. The superior ovary has a single locule formed of three fused carpels and is topped by an erect filiform style and capitate stigma. The fruit is a red berry with few to many seeds. Lapageria rosea, Royal Botanic Gardens, Kew, UK [93]

Distribution: Philesiaceae occur the cool, temperate southern beech (Nothofagaceae) forests of central and southern Chile and the Magellan Straits.

Etymology: The origin was not given, but it is most probably derived from Greek φιλεώ ( phileo), to love, because of its attractive flowers.

Phylogeny and evolution: Philesiaceae have in the past been placed near Smilacaceae and used to include Eustrephus (Asparagaceae), Geitonoplesium (Asphodelaceae) and Luzuriaga (Alstroemeriaceae). They were considered a bridging group between Asparagales and Dioscoreales, but this circumscription is polyphyletic and polymorphic, differing in a number of characters such as leaf venation, tepal structure, placentation and pollen and seed morphology. Molecular analyses have shown the correct placement of these genera, and Philesiaceae now consist of only two species that are sister to Ripogonaceae (it has been suggested that the two families should be merged), and together they are sister to Liliaceae and Smilacaceae. This clade separated from their relatives c. 50 million years ago.

94. RIPOGONACEAE Supplejack family

Uses: Copihue, Lapageria rosea, is the national flower of Chile and a popular, unusual garden ornamental in temperate humid climates. Fruits of Lapageria are edible. Philesia is also sometimes cultivated, but much less commonly so.

These woody, evergreen shrubs and vines have shoots emerging from a stout horizonal rhizome that can be swollen at the base, forming a woody tuber. The long-twining stems are occasionally spiny and lack tendrils but are covered with sheathing scalelike leaves. When these non-leafy stems reach the light, leafy stems emerge that are branched and spreading. Leaves are mostly opposite, sometimes alternate, usually arranged in a plane (distichous) and often have a well-developed drip-tip. Margins are entire, and leaves are usually petiolate and not sheathing at the base. Inflorescences are terminal or axillary racemes, panicles or spikes, the flowers stalked or sessile with bracts. The bisexual, actinomorphic flowers have six free, petal-like, spreading tepals in two whorls. The six stamens have free

Ripogonum discolor, Queensland, Australia (JC) [94]

Ripogonum scandens, fruit, New Zealand (JC) [94]

Genera and species: This family has two genera, each with a single species: Lapageria rosea and Philesia magellanica. An intergeneric hybrid exists.

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LILIALES

MONOCOTS

Smilax guianensis, showing the two petiolar tendrils, Guadeloupe [95]

Smilax aspera, Sicily, Italy [95]

Smilax megalantha, Royal Botanic Gardens, Kew, UK [95]

filaments and greenish, basifixed anthers opening by longitudinal slits. The superior, trilocular ovary is topped by a single style or the stigma sessile on the ovary. The fruit is a berry.

95. SMILACACEAE Catbrier family

Distribution: This Australasian family is found in New Guinea, eastern Australia and New Zealand. Phylogeny and evolution: Fossil Ripogonum is known from the Miocene in New Zealand and the Eocene in Tasmania. Genera and species: The single genus Ripogonum consists of six species. Uses: Stems of Ripogonum have been sometimes used for basketry and building, and the young shoots can been eaten like asparagus. Etymology: Ripogonum is derived from Greek ριπος (ripos), wickerwork, and γόνυ (gony), a knee or node, referring to the long nodose shoots. It is sometimes spelled ‘Rhipogonum’, an orthographic variant. 148

Christenhusz, Fay & Chase

This family of perennial, vines, shrubs and herbs has erect or spiny stems that are usually prickly. Stems sprout from short fibrous, woody, sometimes tuberous rhizomes. Leaves are alternate, opposite or whorled, petiolate, the petiole mostly bearing a pair of tendrils. The leathery leaves are simple and prominently three- to seven-veined with reticulate secondary venation. The umbellate (rarely racemose or spicate) inflorescences are axillary or terminate a branch. Flowers are actinomorphic and unisexual, the male and female flowers borne on different plants. The six tepals are free or united into a perianth tube and are in two

whorls. Male flowers have three to 12 stamens in two or three whorls, the filaments free or fused and the anthers basifixed and opening by longitudinal slits. Female flowers often have staminodes, the superior ovary is trilocular and composed of three carpels (rarely formed of a single carpel), tipped with three spreading styles. Fruits are black, purple or red berries. Distribution: The family is pantropical, extending into the temperate zones north to boreal North America, Mediterranean Europe, the Russian Far East and south into temperate eastern Australia. Phylogeny and evolution: The family is closely related to and was sometimes included in Liliaceae. They differ mainly in leaf characteristics and in being dioecious. Heterosmilax, which was recognised on the basis of its fused tepals and basally fused stamens (free in Smilax s.s.), has now been merged with Smilax. Mediterranean Smilax aspera appears to be sister to the rest of the genus that otherwise comprises a New World and an Old World clade. Many late Cretaceous,

LILIALES

MONOCOTS

Eocene and Miocene fossils of Smilax are known, but a revision of this material is needed to confirm the identification. Divergence in Smilax started c. 40 million years ago. Genera and species: This family consists of the single genus, Smilax, with c. 260 species.

the classical Greek name for Smilax aspera, but oddly it became the modern Greek word for yew (Taxus).

96. LILIACEAE Lily family

Uses: Sarsaparilla (Smilax aristolochiifolia) gives the flavour to root beer and confectionery but was traditionally used as an antisiphilitic. Smilax megacarpa fruits are consumed on Java, where they are made into jam, and S. china is used medicinally to treat gout. The young shoots of many species are eaten in Asia. Etymology: The name is derived from Greek mythology, about love between the mortal man Κρόκος (Krokos) and the nymph Σμίλαξ (Smilax). This dismayed the gods, and the young man was punished and turned into a saffron flower (hence Crocus sativus, Iridaceae) and the poor nymph into a prickly vine. Smilax also gave her name to Fritillaria imperialis, Royal Botanic Gardens, Kew, UK [96]

This family of perennial herbs grows from underground bulbs and creeping rhizomes. The erect, usually leafy, stems sometimes produce bulbils in leaf axils or on the inflorescence. Leaves are alternate or appearing opposite or verticillate, sometimes in a basal rosette or crowded at the apex of the stem. Blades are linear to oval, usually with an acute tip, cirrhose and climbing in some

Fritillaria, sometimes sheathing at the base or amplexicaul (Streptopus). Venation is parallel (in bulbous genera) or reticulate (in some rhizomatous genera). Inflorescences are often single flowered, but can be arranged in thyrses, racemes or umbels, which are often bracteate. The bisexual flowers are usually actinomorphic, the perianth composed of six free tepals in two whorls, which are usually similar, but sometimes whorls are differentiated. Tepals can vary greatly in colour, often having blotches, spots, streaks, checkering or other marks and bearing nectar glands. Sometimes (e.g. Tricyrtis) tepals are pouched or shortly spurred. The six (rarely three) stamens have free filaments that are usually thin and filiform, but can also be flattened, thickened, often glabrous, but sometimes covered in hairs. The dorsally fixed or (pseudo)basifixed anthers open by longitudinal slits. Ovaries are superior, usually trilocular and lacking septal nectaries. A style is present or absent (e.g. in most Tulipa species, in which the stigma is sessile). Fruits are capsules opening by three locules or fleshy berries.

[96]

Lilium candidum, Bucharest Botanical Garden, Romania [96]

Gagea minima, Finland [96]

Erythronium albidum, Royal Botanic Gardens, Kew, UK [96]

Tulipa suaveolens, Keukenhof, the Netherlands

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LILIALES Distribution: This is mostly a North Temperate family that extends south to North Africa, India, subtropical China, Taiwan and Luzon. It is absent from the Southern Hemisphere. Phylogeny and evolution: Many authors circumscribed Liliaceae broadly in the past, but the members that were previously included can now be found spread across families in Alismatales, Asparagales, Dioscoreales, Liliales, Pandanales and Commelinales. Some authors segregated as separate families the genera with either reticulate venation or secondary growth, but this left obviously unrelated taxa in Liliaceae, and placed unrelated taxa in separate families without their close relatives. Iridaceae and Orchidaceae were never included in Liliaceae s.l., but nearly every other member of the above-mentioned orders was at some point in time. Dahlgren et al. (1968) published the first major classification to break with this tradition, and APG restructured these circumscriptions. The crown group of Liliaceae is estimated Scoliopus bigelovii, Royal Botanic Gardens, Kew, UK [96]

Tricyrtis hirta, Jardin des Plantes, Paris [96]

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to have diverged c. 53 million years ago. Reticulately veined, rhizomatous, berryfruited genera are thought to be plesiomorphic in Liliales, and the large-flowered, bulbous, linear-leaved, capsular-fruited genera are more derived. Some generic reorganisation has also occurred. For instance, Lloydia has been merged with Gagea, Nomocharis is embedded in Lilium, and Amana is kept separate from Tulipa. The New World species of Disporum are not related to the Asian members of this genus, and are now placed in the genus Prosartes in Liliaceae. Asian Disporum keep this name and are placed in Colchicaceae. Genera and species: In its current circumscription, this family includes 15 genera with c. 700 species: Amana (4), Calochortus (73), Cardiocrinum (3), Clintonia (5), Erythronium (32), Fritillaria (c. 140), Gagea (204), Lilium (c. 120), Medeola (1), Notholirion (4), Prosartes (6), Scoliopus (2), Streptopus (10), Tricyrtis (20) and Tulipa (c. 75). Calochortus tolmiei, Sea Ranch, California, USA [96]

Fritillaria meleagris, private garden, Kingston upon Thames, Surrey, UK [96]

Uses: Bulbs of Liliaceae are used as food (Amana, Lilium, Tulipa) or for drugs, especially Fritillaria, known in China as ‘beimu’. Good quality starch can be obtained from Cardiocrinum cordatum and Erythronium japonicum. The flower bulb industry of the Netherlands (and elsewhere) thrives on bulbs of especially tulips (Tulipa) and lilies (Lilium) and to a lesser extent Fritillaria. Tulipa and Lilium are also important in the cut-flower industry. Other genera such as Calochortus (mariposa lily), Cardiocrinum (giant lily), Clintonia (beard lily), Erythronium (dog’s tooth violet) and Tricyrtis (poor-man’s orchid) are popular garden plants in the temperate zones. Etymology: Lilium is the classical Latin name for lily, already in use in Roman times. This name was in turn derived from the Greek λείριων (leirion), a name used for pure white lilies like Lilium candidum. That in turn may have been derived from an extinct eastern Mediterranean language that gave the word hleri in Coptic and hrrt in Egyptian, meaning flower. Cardiocrinum giganteum, Royal Botanic Gardens, Kew, UK [96]

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ASPARAGALES Families 97 to 110 comprise the order Asparagales. This order started to diverge c. 119 million years ago, is highly diverse and encompasses the great majority of monocot species.

97. ORCHIDACEAE Orchid family

This is the largest family of vascular plants. Orchids are generally terrestrial or epiphytic herbs, but there are also vines, bamboolike and even shrubby species, although none is truly woody. They can be green and autotrophic or have lost chlorophyll and become mycoheterotrophic, but many green species also maintain mycorrhizal relationships. Plants are rarely entirely underground (Rhizanthella). Some have slightly woody rhizomes, corms or tubers (no true bulbs are known). Stems are often swollen into pseudobulbs. Leaves are alternate, clasping at base, pointed or irregularly emarginate at the tip, and have an entire margin and parallel (rarely reticulate) venation. Blades are sometimes plicately folded, and leaves are rarely opposite, whorled, scalelike or absent. Inflorescences are racemes, panicles or flowers. The inflorescence is sometimes epiphyllous (emerging from a leaf). Flowers are usually bisexual and zygomorphic, although there are orchids with nearly radial symmetry. The three sepals are free or fused at the base and petal-like or green and sepal-like. The three petals are unequal, one of the three is usually modified into a labellum or lip, a showy ornamented petal that can function as a landing platform, or formed as a pouch to guide pollinating insects. The one to three stamens are at least

fused at the base to the style, although often they are fused with the style into a column. Pollen is usually bound tightly into a few (mostly two to six) masses called pollinia. In most cases, when a pollinator visits an orchid flower, it picks up (and later deposits) all of the pollen in that flower. The inferior ovary is composed of three fused carpels, the entire ovary often twisted, and turning the flower upside-down (resupinate). The style is usually fused with the stamens into a simple or variously ornamented column. Fruits are capsules opening by lateral slits with numerous minute seeds, rarely a fleshy berry. In most cases seeds have no stored food, and when germinating they grow into a protocorm which lives off a fungal connection, allowing the plant to become established. Distribution: Orchids are cosmopolitan, with the greatest diversity in the tropics. Phylogeny and evolution: Orchidaceae evolved during the Late Cretaceous, c. 76–105 million years ago, much earlier than originally thought due to their lack of fossil record. This age makes them one of the 15 oldest families of angiosperms. Herbs generally do not fossilise well, and pollen, which from most plants is generally well preserved, is so highly modified in orchids that it would be difficult to recognise in the fossil record. All five orchid subfamilies evolved before the end of the Cretaceous, which means that orchids and dinosaurs overlapped in existence. This was confirmed by the finding of a c. 15–20 million year old fossil bee (Proplebeia dominicana) embedded in Hispaniolan amber. On its back the bee carried pollinia of an extinct orchid, Meliorchis caribea, belonging to Goodyerinae. Using this fossil in a molecular clock analysis, we can see that extant orchid diversity dates back at least

76–84 million years. Considering the great diversity of animals that pollinate orchids nowadays, one can only wonder if any orchids evolved flowers adapted to be pollinated by dinosaurs before the latter went extinct at the Cretaceous-Tertiary boundary (c. 65 million years ago), after which, admittedly, orchids diversified. How to recognise an orchid: The single character that truly unites all Orchidaceae is the formation of a protocorm. This is an undifferentiated ball of cells that grows from the germinating seeds (that in nearly all species have no stored food). This protocorm connects with hyphae (filaments) of particular species of fungi that are permitted to enter the tissue of the protocorm. The great majority of orchid species then go on to develop normal photosynthetic tissues and become less reliant on their fungal connections. This form of endomycorrhizal relationship appears to be completely to the benefit of the orchid because the plants at this early stage have nothing to offer their fungal host. Later on, orchids may provide their fungal associates with carbon, but some orchids remain dependent on a fungal association. These orchids are not photosynthetic and switch their host to a fungal species that forms ectomycorrhizal connections, which occur commonly in many other groups of flowering plants. Normally, ectomycorrhizal species do exchange carbon for minerals and water from the fungi, but obviously if the orchid species is not photosynthetic then there is nothing to be exchanged; it has been demonstrated that carbon produced by nearby trees ends up in the achlorophyllous orchid, with the ectomycorrhizal fungus acting as the intermediate. This complicated life-history strategy is the hallmark of orchids, and the orchid protocorm is the only truly unique

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ASPARAGALES characteristic (synapomorphy) shared by all orchid species. In more general terms, most botanists recognise an orchid by the presence of a structure in the centre of an orchid flower called the column (or gynostemium), which is the product of fusion of the androecium (reduced to a single fertile anther) and gynoecium (three-parted as in most monocots). The column, however, is not universal; it is missing in subfamily Apostasioideae. In Apostasioideae and Cypripedioideae two or three anthers are present. Pollination: Orchids are well known for their elaborate pollination mechanisms that have evolved to achieve cross-pollination. These have fascinated numerous scientists including Charles Darwin, who studied pollination of orchids in detail and was so enthralled by orchids that his first book after the publication of The origin of species was entirely dedicated to orchids. Most orchids produce pollen in tight bundles (two to six), called pollina. These are often attached to ancillary structures that together are called a pollinarium, which attach the pollinia to the body of the pollinator, usually in a position that makes it difficult for the animal to remove the pollen. Few orchids offer their pollinators a reward, but most orchids look as if they contain a reward; some even produce long spurs although they are devoid of nectar. Rates of visitation are notoriously low, and higher rates of pollination are possible if nectar is artificially added to their spurs. However, this increases the rate of pollination by pollen from flowers on the same plant, and it appears that out-crossing is so advantageous for most orchids that low rates of fruit set are the general rule. Having acknowledged this, the combination of delivery of whole pollinaria with a single visit and a correspondingly large number of ovules in the ovary means that from a single visit a massive number of seeds are produced. Many orchids produce large inflorescences with hundreds of flowers (e.g. some species of Dendrobium, Epidendrum and Oncidium), which seems highly wasteful energetically, but production of mature ovules ready for fertilisation is delayed until pollination takes

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place, thus reducing energy input. Orchid seeds are fungal parasites, and most orchid flowers are likewise pollinator parasites and do not offer a reward for pollination. Being such a large family with highly modified floral structures due to pollinator specialisations, floral diversity is enormous. Orchids make use of nearly every species of pollinator used by other angiosperms, and some orchid pollination mechanisms are truly bizarre. Some orchids mimic other flowers that provide rewards. For instance some South American Gomesa species mimic flowers of Malpighiaceae that produce oil collected by euglossine bees. Gomesa is visited by these bees even though it does not produce these oils, but this is because the mimic is nearly perfect, including the absorbance spectrum. Others are even more specialised mimics, including Australian hammer orchid (Drakaea) species that have a hinged lip that resembles a female thynnid wasp. These wasps have flightless females that are picked up by the males; they mate in flight and females are dropped off to lay eggs. The flower even produces pheromone-like substances similar to those that female wasps produce to lure the males. When the males try to pick up the Drakaea lip, they swing into the pollinia which become stuck to the head of the male wasp. When they fall into the trap a second time the orchid is pollinated. Pollination by all sorts of animals is known in orchids, varying from small insects to birds, lizards and small mammals. There is even a species pollinated by a cricket, a group of animals that are only known otherwise to eat flowers, not to pollinate them. Genera and species: Orchidaceae are the largest family of vascular plants with c. 26,460 species in 750 genera, and the family is divided into five subfamilies (Apostasioideae, Vanilloideae, Cypripedioideae, Epidendroideae and Orchidoideae) that are discussed separately below. The largest genera are Bulbophyllum (1,867), Dendrobium (1,509), Epidendrum (1,413), Lepanthes (1,085), Stelis (879), Habenaria (835), Maxillaria (658), Masdevallia (589), Pleurothallis (552) and Liparis (426).

Uses: A great number of orchid species have minor economic usages, but by far the economically most important species is Vanilla planifolia, indigenous to Mexico and now widely cultivated in the tropics. In the absence of a pollinator outside its natural range, the flowers of vanilla are hand pollinated to produce pods. Vanilla is produced commercially from the fermentation of the nearly mature seed capsules, which contain vanillin. Major production areas for commercial vanilla (Vanilla planifolia) are Madagascar and Réunion (e.g. Bourbon vanilla). Tahitian vanilla (V. ×tahitensis) and West Indian vanilla (V. pompona) are minor spice crops as well, both valuable. Additionally, Leptotes bicolor is grown in Paraguay and Brazil for its vanillin-rich seed pods. An ice-cream-like dessert, dondurma, and a cinnamon-flavoured hot drink, salep, is made from orchid tubers in the eastern Mediterranean, especially from Orchis mascula and other species of tribe Orchideae; it is so popular in some areas that extraction from nature of orchid tubers is endangering many species, at least locally. Chikanda is a bread made from the tubers of wild Disa, Habenaria and Satyrium species in East Africa, mainly Zambia. It is so widely consumed there that it is now causing issues in orchid conservation for the adjacent countries. Many orchids are used in the perfume and cosmetics industry, and sometimes flowers are used to flavour drinks. Jumellea fragrans is used to flavour rum in Réunion, threatening this endemic species with extinction. Some species of Dendrobium are so abundant in India that they are used as cattle-fodder. Other species of Dendrobium and Gastrodia (an obligate mycoheterotroph) are widely used in China and other Asian countries in traditional herbal medicine. Orchids are popular ornamental plants, with hybrids of Cattleya, Cymbidium, Oncidium, Phalaenopsis, Paphiopedilum and Vanda being the most widely grown, but most genera can be found in specialist collections. There are currently over 100,000 cultivars (usually hybrids) in the trade, many of them not officially named. Cultivars of Cymbidium and many other genera make attractive, longlasting cut flowers.

ASPARAGALES

MONOCOTS

Apostasia odorata, Vietnam (JL) [97a]

Vanilla pompona subsp. grandiflora, Helsinki Botanical Garden, Finland (PH) [97b]

Vanilla planifolia by M. Smith from Pogonia rosea, Sarah Duke Botanical Garden, Durham, Curtis’s Botanical Magazine vol. North Carolina, USA [97b] 171, 7167 (1891) [97b]

Paphiopedilum lawrenceanum, Ruissalo Botanical Garden, Turku, Finland [97c]

Paphiopedilum venustum, private garden, Irvine, California, USA [97c]

Phragmipedium kovachii, Ecuagenera Cypripedium calceolus, private garden, Cypripedium reginae, private garden, – Orchids from Ecuador, Ecuador [97c] Kingston upon Thames, Surrey, UK Kingston upon Thames, Surrey, UK [97c]

[97c]

Cypripedium fargesii, Royal Horticultural Society alpine show, London, UK [97c]

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ASPARAGALES Etymology: Orchis is derived from the Greek όρχις (orkhis), meaning testicle, in reference to the shape of the root tubers of many Mediterranean species of subfamily Orchidoideae. They are still used as an aphrodisiac in the eastern Mediterranean.

97a. ORCHIDACEAE SUBFAMILY APOSTASIOIDEAE Apostasioids This subfamily consists of terrestrial, rhizomatous herbs, with broad, often plicate leaves. The inflorescences are usually erect racemes or spikes. The flowers differ from standard orchid flowers by having two or three stamens with powdery pollen that is not bound into pollinia. The stamens and pistils are only partially fused into a column. The inferior ovary becomes a dry capsule in fruit. Distribution: This subfamily is restricted to tropical Asia and northern Australia. Phylogeny and evolution: This pair of small genera has often been cited as primitive members of the family, and their floral traits are suggestive of this. However, relative to their chromosome numbers and vegetative features, they are highly derived. In terms of habit, these rhizomatous plants with broad, often plicate leaves are more similar to the related families in Asparagales than to Orchidaceae, especially Hypoxidaceae, with which they are often confused in the vegetative state. Apostasioideae are nevertheless well supported as sister to the rest of orchids and also have a protocorm, a unique character of orchids. Some authors have placed these two genera in their own family, Apostasiaceae, but given their phylogenetic position there is nothing gained by this placement. Genera and species: There are two genera with 14 species: Apostasia (6) and Neuwiedia (8). Etymology: Apostacy, a revolt or departure, is derived from Greek απόστασης (apostasis), distance, refering to the unusual f loral structure (for an orchid, at least) of these plants, which was the basis for some to

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‘distance’ them from orchids and to argue for separate family status.

97b. ORCHIDACEAE SUBFAMILY VANILLOIDEAE Vanillas Many Vanilloideae are vines, some without chlorophyll, but several are terrestrial herbs. All have typical orchid flowers, in that they have a lip and column, the latter with a single anther. Flowers persist on the tip of the ovary long after flowering, and there is often a flange of tissue at the apex of the ovary that persists even longer. Most members of this subfamily also have micro-seeds typical of most orchids, but some genera, such as Vanilla, have larger crustose seeds that resemble those of Hypoxidaceae. This development is presumably a response to the seed dispersal strategy of these genera, which is based on consumption by animals of the highly fragrant capsules (vanillin is released by fermentation while the fruit is attached to the plant); the seeds have to survive the gut of the animal and thus need more protection than the dust-like, thin-walled seeds of most other winddispersed orchids. Distribution: This family is pantropical with a few genera in eastern North America and Japan. Phylogeny and evolution: Vanilloideae are positioned as sister to all other orchids except Apostasioideae, leaving us with the impression that reduction from three to one anther happened more than once in the evolutionary history of Orchidaceae. They are the most recently recognised of the orchid subfamilies, although the family Vanillaceae was already described. Their possession of a single anther led most taxonomists to consider them members of the same subfamily (Epidendroideae) as most tropical epiphytic orchids. Genera and species: Vanilloideae include 14 genera and 245 species: Cleistes (64), Cleistesiopsis (2), Clematepistephium (1), Cyrtosia (5), Duckeella (3), Epistephium (21), Eriaxis (1), Erythrorchis (2), Galeola (6), Isotria (2), Lecanorchis (20), Pogonia (5), Pseudovanilla (8) and Vanilla (105).

Etymology: Vanilla is the diminutive of the Spanish ‘vaina’, a pod, in reference to the production of vanilla from the seed capsule.

97c. ORCHIDACEAE SUBFAMILY CYPRIPEDIOIDEAE Ladies’ slippers These herbaceous perennial, terrestial or epilithic plants, sometimes tall and reed-like (Selenipedium), have a highly constrained floral morphology that makes them unmistakable. They have a pouched lip that functions to trap pollinators inside, only permitting their exit via two openings on either side of the column, which has two anthers that partially block these exits, thereby bringing the pollinator (bees, flies or beetles) into contact with their pollen masses, which are greasy and mostly not formed into tight pollinia (but there are exceptions). The combination of this particular lip structure and two anthers (with a third sterile staminode) is the hallmark of Cypripedioideae. Fruits of Selenipedium are fleshy and ferment to release small amounts of vanillin, not enough for human exploitation, but enough to earn one species the common name of vainilla chica or little vanilla. Other Cypripedioideae have capsular, dry fruits. Distribution: This subfamily occurs in the Northern Hemisphere, tropical America, tropical Asia. Phylogeny and evolution: Cypripedioideae are sister to the remaining two subfamilies, O rch idoidea e a nd Epide nd roidea e. Collectively, the genera have a distribution that probably reflects their origin before the end of the Cretaceous and a Gondwanan association, although they are absent from Africa, presumably due to extinction during the dry periods experienced by this continent during its earlier history. Genera and species: This subfamily includes five genera with 169 species: Cypripedium (51), Mexipedium (1), Paphiopedilum (86), Phragmipedium (26) and Selenipedium (5). Etymology: Cypripedium is derived from Cypris (the Lady of Cyprus) an alternative

ASPARAGALES

MONOCOTS

name for the Greek goddess Aphrodite, and Greek πεδίλων (pedilon), a sandal.

97d. ORCHIDACEAE SUBFAMILY EPIDENDROIDEAE Epidendroids This is by far the largest subfamily of orchids and is nearly impossible to characterise due to the diversity of its members. They include herbs with underground tubers, vines, achlorophyllous fungal holoparasites and a huge number of epiphytic species, some of which have swollen stems (pseudobulbs), and others that are seasonally or habitually leafless (and photosynthesis takes place in their green, exposed roots). Florally, they all have the typical orchid flower, but some have mealy pollen that is not transferred as a unit, whereas others have complicated pollen-bearing ancillary structures, making these the most advanced pollen transfer mechanisms known in flowering plants. No other prominent features are useful for recognising this subfamily; they are distinguished from the second-largest subfamily, Orchidoideae, by their fibrous, often evergreen leaves. Distribution: This cosmopolitan subfamily is most diverse and numerous in the wet tropics at moderate to high elevations. Phylogeny and evolution: Orchidoideae and Epidendroideae are sister taxa; this last major split in the family also took place before the end of the Cretaceous. Unlike many families of flowering plants, the major groups of this subfamily, divided into tribes and subtribes, are restricted to hemispheres and continents, perhaps reflecting patterns of mycorrhizal relationships, particularly during the early stages of germination and establishment. Unfortunately, we still know relatively little about patterns of fungal association among tropical epiphytic species. Genera and species: Currently there are 520 accepted genera and c. 21,100 species: Acampe (8), Acanthephippium (13), Acianthera (118), Acineta (17), Acriopsis (9), Acrolophia (7), Acrorchis (1), Adamantinia

(1), Adenoncos (17), Adrorhizon (1), Aerangis (58), Aeranthes (43), Aerides (25), Aetheorhyncha (1), Aganisia (4), Aglossorrhyncha (13), Agrostophyllum (100), Alamania (1), Alatiliparis (5), Ambrella (1), Amesiella (3), Anathallis (152), Ancistrochilus (2), Ancistrorhynchus (17), Andinia (13), Angraecopsis (22), Angraecum (221), Anguloa (9), Ania (11), Ansellia (1), Anthogonium (9), Aphyllorchis (22), Aplectrum (1), Appendicula (146), Arachnis (14), Arethusa (1), Arpophyllum (3), Artorima (1), Arundina (2), Ascidieria (8), Aspasia (7), Auxopus (4), Barbosella (19), Barkeria (17), Basiphyllaea (7), Batemannia (5), Beclardia (2), Benzingia (9), Biermannia (11), Bifrenaria (21), Bletia (33), Bletilla (5), Bogoria (4), Bolusiella (6), Brachionidium (75), Brachypeza (10), Bracisepalum (2), Braemia (1), Brassavola (22), Brassia (64), Bromheadia (30), Broughtonia (6), Bryobium (8), Bulbophyllum (1867), Bulleyia (1), Calanthe (216), Callostylis (5), Calopogon (5), Caluera (3), Calymmanthera (5), Calypso (1), Calyptrochilum (2), Campanulorchis (5), Campylocentrum (65), Capanemia (9), Cardiochilos (1), Catasetum (176), Cattleya (112), Cattleyella (1), Caucaea (9), Caularthron (4), Centroglossa (5), Cephalanthera (19), Cephalantheropsis (4), Ceratocentron (1), Ceratostylis (147), Chamaeanthus (3), Chamelophyton (1), Changnienia (1), Chaubardia (3), Chaubardiella (8), Chauliodon (1), Cheiradenia (1), Chelonistele (13), Chiloschista (20), Chondrorhyncha (7), Chondroscaphe (14), Chroniochilus (4), Chrysoglossum (4), Chysis (10), Chytroglossa (3), Cirrhaea (7), Cischweinfia (11), Claderia (2), Cleisocentron (6), Cleisomeria (2), Cleisostoma (88), Cleisostomopsis (2), Clowesia (7), Cochleanthes (4), Coelia (5), Coeliopsis (1), Coelogyne (200), Collabium (14), Comparettia (78), Conchidium (10), Constantia (6), Corallorhiza (11), Coryanthes (59), Corymborkis (6), Cottonia (1), Cremastra (4), Crepidium (260), Cribbia (4), Crossoglossa (26), Crossoliparis (1), Cryptarrhena (3), Cryptochilus (5), Cryptopus (4), Cryptopylos (1), Cuitlauzina (7), Cyanaeorchis (3), Cycnoches (34), Cymbidiella (3), Cymbidium (71), Cypholoron (2), Cyrtochiloides (3), Cyrtochilum (137),

Cyrtopodium (47), Cyrtorchis (18), Dactylostalix (1), Daiotyla (4), Danxiaorchis (1), Deceptor (1), Dendrobium (1509), Dendrochilum (278), Dendrophylax (14), Devogelia (1), Diaphananthe (33), Diceratostele (1), Dichaea (118), Dickasonia (1), Didymoplexiella (8), Didymoplexis (17), Dienia (6), Diglyphosa (3), Dilochia (8), Dilochiopsis (1), Dilomilis (5), Dimerandra (8), Dimorphorchis (5), Dinema (1), Dinklageella (4), Diodonopsis (5), Diplocentrum (2), Diploprora (2), Dipodium (25), Distylodon (1), Domingoa (4), Draconanthes (2), Dracula (127), Dresslerella (13), Dressleria (11), Dryadella (54), Dryadorchis (5), Drymoanthus (4), Dunstervillea (1), Dyakia (1), Earina (7), Echinorhyncha (5), Echinosepala (11), Eclecticus (1), Eggelingia (3), Eleorchis (1), Elleanthus (111), Eloyella (10), Embreea (2), Encyclia (165), Entomophobia (1), Ephippianthus (2), Epiblastus (22), Epidendrum (1413), Epilyna (2), Epipactis (49), Epipogium (3), Erasanthe (1), Eria (237), Eriodes (1), Eriopsis (5), Erycina (7), Eulophia (200), Eulophiella (5), Euryblema (2), Eurychone (2), Fernandezia (51), Frondaria (1), Galeandra (38), Galeottia (12), Gastrochilus (56), Gastrodia (60), Gastrorchis (8), Geesinkorchis (4), Geodorum (12), Glomera (131), Gomesa (119), Gongora (74), Govenia (24), Grammangis (2), Grammatophyllum (12), Grandiphyllum (7), Graphorkis (4), Grobya (5), Grosourdya (11), Guanchezia (1), Guarianthe (4), Gunnarella (9), Gynoglottis (1), Hagsatera (2), Hammarbya (1), Hancockia (1), Hederorkis (2), Helleriella (2), Hexalectris (10), Hintonella (1), Hippeophyllum (10), Hoehneella (2), Hofmeisterella (2), Holcoglossum (14), Homalopetalum (8), Horichia (1), Horvatia (1), Houlletia (9), Huntleya (14), Hymenorchis (12), Imerinaea (1), Ionopsis (6), Ipsea (3), Isabelia (3), Ischnogyne (1), Isochilus (13), Ixyophora (5), Jacquiniella (12), Jejewoodia (6), Jumellea (59), Kefersteinia (70), Kegeliella (4), Koellensteinia (17), Kraenzlinella (9), Lacaena (2), Laelia (23), Lemurella (4), Lemurorchis (1), Leochilus (12), Lepanthes (1085), Lepanthopsis (43), Leptotes (9), Limodorum (3), Liparis (426), Listrostachys (1), Lockhartia (28), Loefgrenianthus (1), Lueckelia (1), Lueddemannia (3), Luisia (39), Lycaste (32), Lycomormium (5),

Plants of the World

155

ASPARAGALES

MONOCOTS

Cymbidium devonianum, Royal Horticultural Society Garden, Wisley, UK [97d]

Dendrobium nobile, Helsinki Botanical Garden, Finland [97d]

Bulbophyllum thaiorum, New York Botanical Garden, USA [97d]

Phaius tankervilleae, Royal Botanic Gardens, Kew, UK [97d]

Arundina graminifolia, Singapore Botanical Garden [97d]

Vanda tricolor var. suavis, Santa Barbara Orchid Estate, California, USA [97d] Calypso bulbosa, Mt Tamalpais, California, USA [97d]

Dracula verticulosa, Ecuagenera – Orchids from Ecuador, Ecuador [97d]

Pleurothallis gargantua, Ecuagenera – Orchids from Ecuador, Ecuador [97d]

Restrepia guttulata, Ecuagenera – Orchids from Ecuador, Ecuador [97d]

Oncidium reflexum, Mexico [97d]

Cattleya sincorana, Mucugê, Bahía, Brazil [97d]

156

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Epipactis palustris, Royal Botanic Gardens, Kew, UK [97d]

Porroglossum muscosum, Ecuagenera Brassavola nodosa, New York – Orchids from Ecuador, Ecuador [97d] Botanical Garden, USA [97d]

Cleisostoma birmanicum, New York Botanical Garden, USA [97d]

Kefersteinia trullata, Ecuagenera – Orchids from Ecuador, Ecuador [97d]

ASPARAGALES

MONOCOTS

Ophrys speculum, Sicily, Italy [97e] Disa uniflora, Hampton Court Flower Show, UK [97e] Aa colombiana, Ecuador [97e]

Anacamptis papilionacea, Sicily, Italy [97e]

Habenaria medusa, University of Wisconsin, Madison, USA [97e]

Caladenia flava, near Perth, Western Australia [97e]

Thelymitra variegata, Geraldton, Western Australia [97e]

Orchis militaris, Homefield Wood, England, UK [97e]

Drakaea glyptodon, near Albany, Western Australia [97e]

Pterostylis aspera, Geraldton, Western Australia [97e]

Rhizanthella gardneri, Western Australia (KD) [97e]

Plants of the World

157

ASPARAGALES Macradenia (11), Macroclinium (42), Macropodanthus (8), Malaxis (182), Margelliantha (6), Masdevallia (589), Maxillaria (658), Mediocalcar (17), Meiracyllium (2), Microcoelia (30), Microepidendrum (1), Micropera (21), Microsaccus (12), Miltonia (12), Miltoniopsis (5), Mobilabium (1), Monophyllorchis (1), Mormodes (80), Mycaranthes (36), Myoxanthus (48), Myrmecophila (10), Mystacidium (10), Nabaluia (3), Nemaconia (6), Neobathiea (5), Neoclemensia (1), Neocogniauxia (2), Neogardneria (1), Neogyna (1), Neomoorea (1), Neottia (64), Nephelaphyllum (11), Nephrangis (2), Nervilia (67), Nidema (2), Nohawilliamsia (1), Notheria (15), Notylia (56), Notyliopsis (2), Oberonia (323), Oberonioides (2), Octarrhena (52), Octomeria (159), Oeceoclades (38), Oeonia (5), Oeoniella (2), Oestlundia (4), Oliveriana (6), Omoea (2), Oncidium (311), Ophioglossella (1), Oreorchis (16), Orestias (4), Orleanesia (9), Ornithocephalus (55), Ossiculum (1), Otochilus (5), Otoglossum (13), Otostylis (4), Oxystophyllum (36), Pabstia (5), Pabstiella (29), Pachystoma (3), Palmorchis (21), Panisea (11), Paphinia (16), Papilionanthe (11), Papillilabium (1), Paradisanthus (4), Paralophia (2), Paraphalaenopsis (4), Pelatantheria (8), Pennilabium (15), Peristeranthus (1), Peristeria (13), Pescatoria (23), Phaius (45), Phalaenopsis (70), Phloeophila (11), Pholidota (39), Phragmorchis (1), Phreatia (211), Phymatidium (10), Pilophyllum (1), Pinalia (105), Platyrhiza (1), Platystele (101), Plectorrhiza (3), Plectrelminthus (1), Plectrophora (10), Pleione (21), Pleurothallis (552), Pleurothallopsis (18), Plocoglottis (41), Poaephyllum (6), Podangis (1), Podochilus (62), Pogoniopsis (2), Polycycnis (17), Polyotidium (1), Polystachya (234), Pomatocalpa (25), Ponera (2), Porpax (13), Porphyroglottis (1), Porroglossum (43), Porrorhachis (2), Promenaea (18), Prosthechea (117), Pseuderia (20), Pseudolaelia (18), Psilochilus (7), Psychilis (14), Psychopsiella (1), Psychopsis (4), Pteroceras (27), Pterostemma (3), Pygmaeorchis (2), Quekettia (4), Quisqueya (4), Rangaeris (6), Rauhiella (3), Renanthera (20), Restrepia (53), Restrepiella (2), Rhaesteria (1), Rhinerrhiza (1), Rhinerrhizopsis (3), Rhipidoglossum (35), Rhynchogyna (3),

158

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MONOCOTS

Rhyncholaelia (2), Rhynchostele (17), Rhynchostylis (3), Ridleyella (1), Risleya (1), Robiquetia (45), Rodriguezia (48), Rossioglossum (9), Rudolfiella (6), Saccolabiopsis (14), Saccolabium (5), Sanderella (2), Santotomasia (1), Sarcanthopsis (5), Sarcochilus (25), Sarcoglyphis (12), Sarcophyton (3), Sarcostoma (5), Saundersia (2), Scaphosepalum (46), Scaphyglottis (69), Schistotylus (1), Schlimia (7), Schoenorchis (25), Schunkea (1), Scuticaria (11), Seegeriella (2), Seidenfadenia (1), Seidenfadeniella (2), Sertifera (7), Sievekingia (16), Singchia (1), Sirhookera (2) Smithsonia (3), Smitinandia (3), Sobennikoffia (4), Sobralia (149), Solenangis (8), Solenidium (3), Soterosanthus (1), Spathoglottis (48), Specklinia (135), Sphyrarhynchus (1), Spongiola (1), Stanhopea (61), Stelis (879), Stenia (22), Stenotyla (9), Stereochilus (7), Stereosandra (1), Stichorkis (8), Stolzia (15), Suarezia (1), Sudamerlycaste (42), Summerhayesia (2), Sutrina (2), Systeloglossum (5), Taeniophyllum (185), Taeniorrhiza (1), Tainia (23), Tamayorkis (1), Taprobanea (1), Teagueia (13), Telipogon (205), Tetramicra (14), Teuscheria (7), Thaia (1), Thecopus (2), Thecostele (1), Thelasis (26), Thrixspermum (161), Thunia (5), Thuniopsis (1), Thysanoglossa (3), Tipularia (7), Tolumnia (27), Tomzanonia (1), Trachoma (14), Trevoria (5), Triceratorhynchus (1), Trichocentrum (70), Trichoceros (10), Trichoglottis (69), Trichopilia (44), Trichosalpinx (111), Trichotosia (78), Tridactyle (47), Triphora (18), Trisetella (23), Trizeuxis (1), Tropidia (31), Tuberolabium (11), Uleiorchis (2), Uncifera (6), Vanda (73), Vandopsis (4), Vargasiella (1), Vasqueziella (1), Vitekorchis (4), Warczewiczella (11), Warmingia (4), Warrea (3), Warreella (2), Warreopsis (4), Wullschlaegelia (2), Xerorchis (2), Xylobium (30), Yoania (4), Ypsilopus (5), Yunorchis (1), Zelenkoa (1), Zootrophion (22), Zygopetalum (14), Zygosepalum (8) and Zygostates (22).

Phylogeny and evolution: As indicated above, Orchidoideae are sister to Epidendroideae and parallel their patterns of distribution, except that this subfamily has specialised to a greater degree in temperate zones, both northern and southern. Previous taxonomists recognised subfamily Spiranthoideae as distinct from Orchidoideae, based largely on the replacement of root tubers found predominantly in the latter with the fat roots of the former, but molecular phylogenetic studies demonstrated that Spiranthoideae are embedded in Orchidoideae, leading to recognition of an expanded Orchidoideae.

Etymology: Epidendrum is composed of the Greek prefix επί (epi) meaning ‘on’ and δένδρων (dendron), a tree, referring to the epiphytic habit of many species of Epidendrum, the single genus into which Linnaeus originally placed all tropical epiphytic orchids.

Genera and species: Currently there are 217 accepted genera and 4,965 species: Aa (25), Aceratorchis (1), Achlydosa (1), Acianthus (20), Adenochilus (2), Aenhenrya (1), Altensteinia (7), Amitostigma (27), Amitostigma (27), Anacamptis (11), Androcorys (10), Anoectochilus (43), Aporostylis (1), Aracamunia (1), Arthrochilus

97e. ORCHIDACEAE SUBFAMILY ORCHIDOIDEAE Orchidoids The habits of this subfamily are less diverse than those of their sister clade, Epidendroideae. The majority of Orchidoideae are deciduous or soft-leaved herbs (without fibres) with root tubers or fat elongate roots. Like Epidendroideae, these plants have typical orchid flowers adapted for pollination by a wide variety of animals. Pollen is in general not bound into tight masses, and in some cases multiple visits have been recorded before most pollen is removed from a flower. The majority of the species use deceit-pollination without reward to the pollinator, and in both the North and South Temperate zones genera have become adapted for pollination by male insects that mistake the flowers for female members of their species; floral scents of such species also mimic the sex pheromones of female insects. Fruits are generally dry, many-seeded capsules. Distribution: This cosmopolitan group has centres of diversity in Australia, South Africa and the Mediterranean.

ASPARAGALES

MONOCOTS

(15), Aspidogyne (45), Aulosepalum (7), Bartholina (2), Baskervilla (10), Beloglottis (7), Benthamia (29), Bhutanthera (5), Bidoupia (1), Bipinnula (11), Bonatea (13), Brachycorythis (36), Brachystele (21), Brownleea (8), Buchtienia (3), Burnettia (1), Caladenia (267), Caleana (1), Calochilus (27), Centrostigma (3), Ceratandra (6), Chamaegastrodia (3), Chamorchis (1), Cheirostylis (53), Chiloglottis (23), Chloraea (52), Coccineorchis (7), Codonorchis (1), Coilochilus (1), Corybas (132), Corycium (15), Cotylolabium (1), Cranichis (53), Cryptostylis (23), Cyanicula (10), Cybebus (1), Cyclopogon (83), Cynorkis (156), Cyrtostylis (5), Cystorchis (21), Dactylorhiza (40), Danhatchia (1), Degranvillea (1), Deiregyne (18), Dichromanthus (4), Diplomeris (3), Disa (182), Discyphus (1), Disperis (78), Diuris (71), Dossinia (1), Dracomonticola (1), Drakaea (10), Eltroplectris (13), Elythranthera (2), Epiblema (1), Ericksonella (1), Eriochilus (9), Erythrodes (26), Eurycentrum (7), Eurystyles (20), Evotella (1), Fuertesiella (1), Funkiella (27), Galearis (10), Galeoglossum (3), Galeottiella (6), Gavilea (15), Gennaria (1), Genoplesium (47), Glossodia (2), Gomphichis (24), Gonatostylis (2), Goodyera (98), Greenwoodiella (3), Gymnadenia (23), Habenaria (835), Halleorchis (1), Hapalorchis (10), Helonoma (4), Hemipilia (13), Herminium (19), Herpysma (1), Hetaeria (29), Himantoglossum (11), Holothrix (45), Hsenhsua (1), Huttonaea (5), Hylophila (7), Kionophyton (4), Kipandiorchis (1), Kreodanthus (14), Kuhlhasseltia (9), Lankesterella (11), Lepidogyne (1), Leporella (1), Leptoceras (1), Ligeophila (12), Ludisia (1), Lyperanthus (2), Lyroglossa (2), Macodes (11), Manniella (2), Megalorchis

(1), Megastylis (7), Mesadenella (7), Mesadenus (7), Microchilus (137), Microtis (19), Myrmechis (17), Myrosmodes (12), Neobolusia (3), Neotinea (4), Nothostele (2), Odontochilus (25), Odontorrhynchus (6), Oligophyton (1), Ophrys (34), Orchipedum (3), Orchis (21), Orthoceras (2), Pachites (2), Pachyplectron (3), Papuaea (1), Paracaleana (13), Pecteilis (8), Pelexia (77), Peristylus (103), Pheladenia (1), Physoceras (12), Physogyne (3), Platanthera (136), Platycoryne (19), Platylepis (17), Platythelys (13), Ponerorchis (55), Ponthieva (66), Porolabium (1), Porphyrostachys (2), Praecoxanthus (1), Prasophyllum (131), Prescottia (26), Pseudocentrum (7), Pseudogoodyera (1), Pseudorchis (1), Pterichis (20), Pteroglossa (11), Pterostylis (211), Pterygodium (19), Pyrorchis (2), Quechua (1), Rhamphorhynchus (1), Rhizanthella (3), Rhomboda (22), Rimacola (1), Roeperocharis (5), Sacoila (7), Sarcoglottis (48), Satyrium (86), Sauroglossum (11), Schiedeella (22), Schizochilus (11), Schuitemania (1), Serapias (13), Shizhenia (1), Silvorchis (3), Sirindhornia (3), Skeptrostachys (13), Solenocentrum (4), Sotoa (1), Spiculaea (1), Spiranthes (34), Stalkya (1), Stenoglottis (7), Stenoptera (7), Stenorrhynchos (5), Stephanothelys (5), Steveniella (1), Stigmatodactylus (10), Svenkoeltzia (3), Thelymitra (110), Thelyschista (1), Thulinia (1), Townsonia (2), Traunsteinera (2), Tsaiorchis (1), Tylostigma (8), Veyretella (2), Veyretia (11), Vrydagzynea (43), Waireia (1) and Zeuxine (74). Etymology: Greek όρχις (orkhis) means testicle, refering to the shape of the root tubers of many Mediterranean species of subfamily Orchidoideae.

Borya sphaerocephala, Geraldton, Western Australia [98]

98. BORYACEAE Pincushion-lily family

This is a family of perennial shrubby herbs forming tufts, clumps or cushions. The woody stems are branched and form fibrous, wiry, sometimes stilt-like roots. Sessile linear leaves are placed spirally around the stem, are sheathing at the base and often have a sharp tip. Venation is parallel. Inflorescences are often dense, terminal spikes or racemes, surrounded by involucral bracts, often condensed to appear capitate. White flowers are bisexual and actinomorphic, with two whorls of three similar, free or basally fused tepals. The six stamens are free or fused with the tepals, and the basifixed anthers open by longitudinal slits. The superior ovary is trilocular and bears septal nectaries that resemble external nectar slits on the ovary wall. The ovary is topped with a single style and a capitate stigma. The fruit is a capsule that splits in three. Distribution: This family is endemic to Australia. Borya are resurrection plants found in exposed xeric environments where they have a unique adaptation to desiccation, at which stage they turn rusty reddish-orange

Borya sphaerocephala, Perth, Western Australia [98]

Plants of the World

159

ASPARAGALES only to become green and start growing again when rain occurs. By contrast, Alania is found in constantly moist habitats. Phylogeny and evolution: The crown group of Boryaceae is dated to be 54 million years old. The family was previously associated with Anthericaceae or Asparagaceae, but molecular analyses place Boryaceae as sister to a clade that includes Asteliaceae and Hypoxidaceae. Genera and species: This family has two genera with a dozen species: Alania (1) and Borya (11). Etymology: The Australian genus Borya was named to commemorate French naturalist Jean Baptiste Bory de Saint-Vincent (1778–1846), who embarked on an expedition to Australia in 1798, but disembarked in Mauritius and explored the Mascarene Islands instead.

99. BLANDFORDIACEAE Christmas-bells family

MONOCOTS

These perennial herbs grow in tufts from short tuber-like rhizomes. The alternate sessile leaves are placed in a fan (distichous) and sheath the rhizome at the base. Blades are linear with many parallel veins, secondary crossveins and a prominent midvein. Inflorescences grow terminally from the rhizome and are racemes that in some species can grow up to 1.5 m tall. The bisexual flowers are actinomorphic to slightly zygomorphic and pedicels are enveloped by a scale-like bract. The petal-like tepals are fused to form a bell-shaped tube with six broad lobes. The six stamens are attached to the lower part of the perianth tube, and anthers are dorsifixed and open by latrorse slits. A trilocular superior ovary tapers below to form a stalk (gynophore), and septal nectaries are present as external grooves. The ovary is tipped with a single erect style and a three-grooved stigma. The fruit is a capsule that splits in three.

160

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Genera and species: The single genus Blandfordia consists of four species. Uses: Some species are cultivated as ornamentals and for cut flowers. Etymology: Blandfordia was named in honour of George Spencer-Churchill, the fifth Duke of Marlborough and Marquis of Blandford (1766–1840), a collector of books and antiquities.

100. ASTELIACEAE Pineapple-grass family

Distribution: This family is restricted to eastern Australia and Tasmania. Phylogeny and evolution: Blandfordia was traditionally associated with Hemerocallis, Kniphofia, Phormium or even Dasypogonaceae. Molecular analyses placed the genus in an isolated position among Asteliaceae, Boryaceae and Hypoxidaceae. Morphological similarities between Boryaceae

Blandfordia nobilis, Australia (KD) [99]

and Blandfordiaceae are evident, which may be plesiomorphic for the larger clade.

Blandfordia cunninghamii by W. Fitch from Curtis’s Botanical Magazine vol. 94: plate 5734 (1868) [99]

These perennial short-stemmed tufted herbs usually grow terrestrially but are sometimes found as epiphytes. Plants are either male or female (except in Milligania), and they are characterised by the peculiar indumentum of scales. Leaves are spirally arranged, usually three-ranked, linear to ensiform and deeply keeled with a broad, closed sheathing base. Leaves are densely parallel veined and usually densely hairy (the hairs branched) at least when young. Inflorescences are terminal compound panicles composed of reduced racemes, each raceme with a spathe-like bract, the bracteoles usually on short pedicels. The unisexual, actinomorphic flowers are usually tri- sometimes pentamerous, the tepals usually six in two equal whorls, free or fused at the base to form a tube. In male flowers, six stamens are free or fused to the perianth tube, with dorsifixed to basifixed anthers that open by longitudinal slits. Female flowers have six staminodes surrounding the superior ovary that is composed of three to seven carpels forming one to three locules.

ASPARAGALES

MONOCOTS

Slit-like septal nectaries are present on the ovary around the short and thick style between the stigmatic surfaces. The fruit is a berry or a capsule. Distribution: This mostly Southern Hemisphere family has a patchy distribution, Asteliaceae can be found in southern South America, the Falkland Islands, the Mascarene Islands, New Guinea, southern Australia and New Zealand and from New Caledonia to Polynesia and Hawaii. Phylogeny and evolution: Fossils of Astelia are known from the Upper Eocene of New Zealand. The group has been dated to be c. 92 million years old. Collospermum is embedded in Astelia and should be merged with that genus. The position of Milligania is uncertain, but may together with Neoastelia form the

sister to Astelia. Long-distance dispersal must be common in this family, given the broad distribution and occurrence on recently formed oceanic islands. They share branched hairs with Hypoxidaceae and Lanariaceae and mucilage canals with Hypoxidaceae, the former perhaps a synapomorphy of the hypoxid clade minus Blandfordiaceae.

101. LANARIACEAE Lambtails family

Genera and species: This family has three genera and 37 species; Astelia (31), Milligania (5) and Neoastelia (1). Uses: Fruits of Astelia nervosa are edible, and fibre of A. grandis is used for handicrafts in New Zealand. Etymology: Astelia is composed of the Greek prefix α- (a-), not, and στήλη (steli), a column, in reference to the lack of a stem or trunk.

Astelia hemichrysa, infructescence, Réunion [100]

These are perennial herbs with short erect rhizomes that produce roots in the lower part and have spirally arranged leaves around the tip. Glabrous, linear leaves are sessile, have a closed sheath at the base and are parallel veined. Inflorescences are dense corymbose panicles on a long-bracted scape, and all parts of the inflorescence are densely woolly, with branched hairs. Bisexual, actinomorphic flowers are covered with dense woolly hairs outside and are pale mauve or purple inside. Six equal tepals are fused into a tube for the lower half, and six anthers are fused to this tube. The inner three stamens are shorter than the outer three, and anthers are dorsifixed and open by longitudinal slits. The inferior ovary is trilocular, has septal nectaries and is topped Lanaria lanata, South Africa (JA) [101]

Astelia neocaledonica, Royal Botanic Gardens, Melbourne, Australia [100]

Lanaria lanata, South Africa (JA) [101]

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ASPARAGALES with a narrow filiform style. The fruit is a capsule with a single seed.

MONOCOTS

102. HYPOXIDACEAE Stargrass family

Distribution: The family is restricted to the southern coast of the Cape Province of South Africa, from Somerset Bay to Albany, where it grows in fynbos vegetation. Phylogeny and evolution: Previously Lanaria was associated with Haemodoraceae, which it resembles in inflorescence morphology and hairy flowers. It had also been thought to have a relationship with Lophiola (Nartheciaceae), but this was refuted on the basis of differences in leaf morphology, anatomy and molecular phylogenetics. Lanaria is sister to Hypoxidaceae, with which it shares several characters but lacks mucilage canals, which are present in both Asteliaceae and Hypoxidaceae.

Etymology: Lanaria is derived from Latin, lana, wool, in reference to the woolly cottonlike appearance of the plant.

This family of perennial herbs forms a tuberous rhizome or corm that is covered with membranous, fibrous remains of former leaf sheaths. Leaves are all basal, alternately arranged in three ranks at the apex of the rhizome. They can be sessile or petiolate (Curculigo) and sheathing at the base. Blades are linear to lanceolate and hairy, the hairs branched, often along margins, or glabrous, usually V-shaped in cross-section or plicate and palm-like (in Curculigo). Inflorescences are spikes, corymbs or false umbels that are usually on hairy scapes arising from the leaf axils. The bisexual flowers emerge from axils of bracts that can be small or large and leafy.

Curculigo seychellensis, Mahé, Seychelles [102]

Hypoxis setosa, Royal Horticultural Society Garden, Wisley, UK [102]

Genera and species: The family consists of the single species Lanaria lanata.

Curculigo capitulata, Gunung Datuk, Malaysia [102]

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Smaller cleistogamous flowers are sometimes present. The six (rarely four) tepals form two equal whorls and are petal-like, often yellow, white or pink, sometimes red or maroon. They are free or basally fused into a tube and are more or less persistent in fruit. Usually six (sometimes three) stamens are inserted at the base of perianth segments and have short filaments and basifixed or dorsifixed anthers that open by longitudinal slits. The inferior ovary is trilocular, topped with a short style and three stigmas that can have free lobes or grooves along the style. The fruit usually is a capsule crowned by the persistent perianth that opens irregularly, often by circular slits, sometimes the fruit is a fleshy berry. Distribution: This pantropical family extends into temperate North America, southern Japan and Australia but is absent from Europe and the Middle East. It is especially diverse in temperate South Africa. Phylogeny and evolution: The crown group Hypoxidaceae have been dated to c. 78 million years ago. In older classifications, Hypoxidaceae were included in Amaryllidaceae. Hypoxis baurii, Royal Botanic Gardens, Kew, UK [102]

ASPARAGALES

MONOCOTS

Etymology: Hypoxis is an ancient Greek name for plants with somewhat acid leaves, from υπό (hypo), below and οξύς (oxys), sharp; later used for this genus by Linnaeus.

These giant, tufted, evergreen perennials make short underground stems from which the numerous long, spirally arranged, linear to lanceolate leaves grow. Their roots are thick and fleshy, and the leaf bases are filled with starch and form a bulb-like structure; leaf tips have a tubular brown tip that withers away to leave a tuft of thread-like fibres. Inf lorescences are large terminal

slightly or densely contracted thyrses that can grow up to five and a half metres tall and terminate a scape that at the base is covered with leaf-like bracts; towards the apex flowers and inflorescence branches are subtended by bright red bracts. The large bisexual flowers are on short pedicels, each bearing a prophyll. The six petallike tepals are united at the base in a tube that encloses the ovary, forming a nectar cup. The six stamens are fused with the perianth tube for about half their length; anthers are connected to the filament in a tube formed by the connective, the thecae opening by longitudinal slits. The inferior ovary is trilocular and has well-developed septal nectaries that open around the base of the style and fill the nectar cup. The simple slender style has a blunt triangular stigma. The fruit is a capsule that splits in three, exposing laterally winged seeds.

Doryanthes palmeri, Adelaide Botanic Garden, South Australia [103]

Doryanthes excelsa, Australian National Botanic Gardens, Canberra [103]

Doryanthes excelsa, Australian National Botanic Gardens, Canberra [103]

On the basis of morphology, a relationship to Orchidaceae has been suggested. On the basis of recent molecular studies, the family is redefined to include only four genera, with Curculigo including Hypoxidia and Molineria, Hypoxis including Rhodohypoxis, and Pauridia including Spiloxene and most Australian species of Hypoxis. Genera and species: Hypoxidaceae include four genera and c. 160 species: Curculigo (25), Empodium (7), Hypoxis (97) and Pauridia (c. 30). Uses: Curculigo capitulata and Hypoxis baurii (and cultivars) are grown as ornamentals.

Doryanthes palmeri, with Maarten Christenhusz for scale, Adelaide Botanic Garden, South Australia [103]

103. DORYANTHACEAE Gymea-lily family

Ixiolirion tataricum, Royal Botanic Gardens, Kew, UK [104]

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ASPARAGALES Distribution: This family is restricted to eastern Australia, where it is found between Jervis Bay and Burkedin River, in rocky gullies near the coast. Phylogeny and evolution: Doryanthes was thought to be closely related to Phormium (Asphodelaceae), but it is distant from that genus, instead forming a clade with Ixioliriaceae and Tecophilaeaceae and is now placed in its own family. Fossils 75–70 million years old assigned to Doryanthaceae or Iridaceae have been found in Late Cretaceous rocks of eastern Siberia. The split between Doryanthaceae and Iridaceae has been estimated by molecular clock to be at least c. 82 million year old, but another estimated age for this lineage is 107 million years. Genera and species: The single genus Doryanthes consists of two species: D. excelsa and D. palmeri. Uses: Both species are sometimes cultivated as ornamentals in Australia, and are an important food source for birds, mainly honeyeaters. Etymology: Doryanthes is composed of the Greek δόρυ (dory), a spear, and άνθος (anthos), a flower.

104. IXIOLIRIACEAE Tartar-lily family

MONOCOTS

bear a prophyll. The bisexual actinomorphic flowers have six petal-like tepals in two equal whorls, which are free nearly to the base. The outer tepals end in a prominent tip just below the apex. The six stamens are inserted at the base of the tepals and have basifixed anthers that open by longitudinal slits. The inferior ovary is trilocular and tipped with a slender style that is split in three at the dry stigmatic area. The fruit is a dry capsule that splits at the top revealing the numerous black seeds. Distribution: This family is found in semiarid lands of southwestern and inner Asia, from Egypt and the Levant to Central Asia. Phylogeny and evolution: In the past Ixiolirion was placed in Amaryllidaceae, but the position in that family has always been uncomfortable due to its corm, leafy scapes, blue flowers, lack of alkaloids and presence of simultaneous sporogenesis, all rare in Amaryllidaceae. Molecular analyses placed Ixiolirion with Doryanthes and Tecophilaeaceae in proximity to Iridaceae in Asparagales, supporting this placement as a separate family, although it could potentially be merged with Tecophilaeaceae, with which it shares many characters. Genera and species: The single genus Ixiolirion consists of four species. Uses: Ixiolirion tataricum is sometimes available in the ornamental bulb trade. Etymology: Ixiolirion is derived from the Greek ιξιά (ixia), bird lime, and λείριων (leirion), a lily.

105. TECOPHILAEACEAE Chilean-crocus family

These are perennial herbs with tunicate corms that renew from the base plate. Stems are erect, leafy and unbranched. Flat linear leaves alternate along the stem are sheathing at the base with a cylindrical apex. Inflorescences are thyrses or false umbels with few to many blue, violet or white flowers on pedicels that

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These perennial herbs grow from a globose or ellipsoid underground corm, from which leaves and stems emerge. Leaves are basal or (in Walleria) alternate along the stem, and are usually sheathing at the base, but not always. The simple leaves are sessile and linear-lanceolate or (in Cyanastrum and Kabuyea) lanceolate and ovate with a distinct petiole, and sometimes with a cordate base. Venation is parallel or parallel-arching in broader leaves with transverse secondary veins, the midvein often pronounced. Flowers are formed in panicles or solitarily in the leaf axils, often with bracts or breacteoles on the pedicel or peduncle. The bisexual flowers are actinomorphic or zygomorphic, and the six petal-like tepals are fused at the base and arranged in two whorls. The corona is sometimes adorned with minute appendages between the stamens. The six stamens arise at the mouth of the perianth tube, and some of these are sometimes staminodial. Stamens are regular in actinomorphic flowers, facing one side of the flower (often upwards) in zygomorphic flowers. The fertile anthers are basifixed or nearly so and open by pores. The ovary is semi-inferior or nearly superior and is composed of three carpels forming three locules. The fruit is a capsule that splits into three, exposing the black or brown seeds. Distribution: This disjunct family is found in California, Chile and Sub-Saharan Africa. Phylogeny and evolution: The family was previously associated with Haemodoraceae, but the presence of simultaneous microsporogenesis, phytomelan in the seed coat and the absence of cell-wall ferulates place this family in Asparagales. Molecular evidence shows that it is related to Ixioliriaceae, Doryanthaceae and Iridaceae. The crown group of Tecophilaeaceae are dated to be 77–87 million years old. Their biogeography is complex, and colonisation of the family in what are now Mediterranean ecosystems must have happened before this type of climate was present in these areas. The South American genera Conanthera and Zephyra appear to be sister to the rest of the family, although in some studies Tecophilaea takes this position.

ASPARAGALES

MONOCOTS

Conanthera bifolia, Royal Botanic Gardens, Kew, UK [105]

Odontostomum hartwegii, Royal Botanic Gardens, Kew, UK [105]

Tecophilaea cyanocrocus, Royal Botanic Gardens, Kew, UK

Genera and species: This small family of nine genera has 27 species: Conanthera (5), Cyanastrum (3), Cyanella (9), Eremiolirion (1), Kabuyea (1), Odontostomum (1), Tecophilaea (2), Walleria (3) and Zephyra (2).

This family includes mostly perennial herbs, rarely shrubs (Klattia, Nivenia, Witsenia) or annuals that are usually chlorophyllous and autotrophic apart from Geosiris, which is a mycoheterotrophic herb lacking chlorophyll. Plants are evergreen or seasonal, sometimes clump-forming, with rhizomes, corms or bulbs, rarely with a woody caudex or with an indistinct rootstock. Leaves are formed basally or along the stem, sheathing at the base with an open or closed sheath, often in one plane (distichous) with the bases usually overlapping (equitant), the blades flattened, often unifacial and oriented with their edge towards the stem, or terete, rarely with false petioles and broadened blades. Veins are parallel, with or without a distinct midvein, the surface flat, ribbed or plicate. Leaves are scale-like in Geosiris. Flowering stems are usually aerial (subterranean at anthesis in Romulea) and are simple or branched, round or flattened and angular or winged. Inflorescences are umbellate cymes (rhipidia), arranged in panicles, spikes or randomly clustered on terminal or lateral branches. Rhipidia comprise pedicellate or nearly sessile flowers subtended by a bract (or spathe) that encloses the flower until anthesis, sometimes reduced to a spike of sessile flowers subtended by opposite bracts or reduced to single flowers. The bisexual actinomorphic or zygomorphic flowers are

Uses: Apart from occasionally being grown as ornamental plants (especially Cyanastrum cordifolium and Tecophilaea cyanocrocus), this family has no economic importance. Tecophilaea cyanocrocus was previously thought to be extinct in the wild, but new populations have since been found. Collecting from the wild is still prohibited. Etymology: Tecophilaea was named by Italian botanist Luigi Aloysius Colla (1766–1848) for his daughter, botanical artist Tecophila Colla-Billotti.

106. IRIDACEAE Iris family

[105]

Cyanella lutea, Royal Botanic Gardens, Kew, UK [105]

composed of two whorls or three petal-like tepals, the inner whorl sometimes suppressed, when zygomorphic the flower often two-lipped, the upper tepal often enlarged and hooded. Tepals are free or fused into a tube, often bearing nectaries and nectar guides. Stamens are usually three (two in Diplarrena) and inserted at the base of the outer tepals or inside the tube. They can be symmetrically arranged in actinomorphic flowers or are unilateral and curved in zygomorphic ones. Filaments are free or completely fused, the anthers are basifixed to centrifixed with the two thecae usually opening by longitudinal slits. The inferior (superior only in Isophysis) ovary is trilocular and topped by a single filiform style that is branched or lobed in three at the tip. The fruit is a capsule that generally splits in three, rarely indehiscent, exposing the seeds that can be simple, usually dry and brown, but sometimes winged or covered with a red aril. Distribution: This is a cosmopolitan family that is patchy in tropical Asia and absent from true deserts. Phylogeny and evolution: Iridaceae diverged from the remaining Asparagales c. 80 million years ago in the Late Cretaceous. Isophysis (now restricted to Tasmania) may have diverged from the rest of the family c. 66

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ASPARAGALES

166

MONOCOTS

Diplarrena moraea, private garden, Kingston upon Thames, Surrey, UK [106]

Tigridia pavonina, private garden, Kingston upon Thames, Surrey, UK [106]

Sisyrinchium bellum, California, USA [106]

Gladiolus carmineus, Royal Botanic Gardens, Kew, UK [106]

Crocus sativus, Royal Botanic Gardens, Kew, UK [106]

Iris pseudacorus, Kew Green, Richmond, Surrey, UK [106]

Moraea sisyrinchium, Ronda, Spain [106]

Lapeirousia oreogena, Royal Botanic Gardens, Kew, UK [106]

Orthrosanthus laxus, Mt Benia, Western Australia [106]

Christenhusz, Fay & Chase

ASPARAGALES

MONOCOTS

million years ago. Most other early-branching lineages are also of Australasian origin, and it is therefore hypothesised that Iridaceae has an Australian-Antarctic origin from where it dispersed across the globe. Their current centres of diversity are in the Andes and Southern Africa, where they diversified from the Eocene onwards. Iridaceae are currently divided into seven subfamilies (Aristeoideae, Crocoideae, Geosiridoideae, Iridoideae, Isophysidoideae, Nivenioideae and Patersonioideae) based on morphological characters and the results of molecular analyses. Isophysidoideae comprise Isophysis tasmanica with a superior ovary; it is sister to the rest of Iridaceae. Patersonioideae are only found in Australia and often lack the inner whorls of tepals. Shrubby Nivenioideae are sister to the cormous Crocoideae, but sometimes include Patersonioideae as a section. Recent molecular studies have resulted in the reorganisation of a number of genera: e.g. Schizostylis is now placed in Hesperantha; Belamcanda, Juno, Pardanthus and Hermodactylus are merged with Iris; Acidanthera is part of Gladiolus, Anomatheca belongs to Freesia, and Homeria and Gynandriris have been merged with Moraea. Genera and species: Iridaceae include 66 genera and c. 2,244 species, in seven subfamilies. Isophysidoideae – Isophysis (1); Iridoideae – Alophia (5), Bobartia (15), Calydorea (22), Cipura (8), Cobana (1), Cypella (33), Dietes (6), Diplarrena (2), Eleutherine (4), Ennealophus (5), Ferraria (18), Gelasine (7), Herbertia (9), Hesperoxiphion (5), Iris (281), Lethia (1), Libertia (16), Mastigostyla (27), Moraea (206), Nemastylis (6), Neomarica (28), Olsynium (17), Orthrosanthus (9), Phalocallis (1), Pseudiris (1), Pseudotrimezia (18), Sisyrinchium (200), Solenomelus (2), Tapeinia (1), Tigridia (54) and Trimezia (28); Patersonioideae – Patersonia (25); Geosiridoideae – Geosiris (2); Aristeoideae – Aristea (56); Nivenioideae – Klattia (3), Nivenia (11) and Witsenia (1); Crocoideae – Babiana (92), Chasmanthe (3), Crocosmia (8), Crocus (104), Cyanixia (1), Devia (1), Dierama (43), Duthiastrum (1), Freesia (16), Geissorhiza

(97), Gladiolus (276), Hesperantha (84), Ixia (79), Lapeirousia (41), Melasphaerula (1), Micranthus (3), Pillansia (1), Radinosiphon (2), Romulea (111), Savannosiphon (1), Sparaxis (15), Syringodea (8), Thereianthus (11), Tritonia (28), Tritoniopsis (23), Watsonia (52), Xenoscapa (3) and Zygotritonia (4). Uses: Stigmas of Crocus sativus are the source of the expensive spice, saffron. They are grown on a commercial scale in Spain, Morocco, India and Turkey. Corms of Crocus, Lapeirousia and Moraea fugax are locally eaten. Starch of orris root, Iris pallida, was formerly used medicinally, for perfumes and to flavour gin. Many genera are grown as ornamentals, especially Babiana, Crocosmia, Crocus, Dierama, Freesia, Gladiolus, Hesperantha, Iris, Ixia, Libertia, Moraea, Neomarica, Sisyrinchium, Sparaxis, Tigridia, Tritonia and Watsonia. For the cut-f lower industry, Freesia, Gladiolus, Iris and Ixia are important. Many species escape from cultivation and cause considerable trouble as invasives, crowding out native plants. Etymology: Iris (Ίρις) is the ancient Greek goddess of the rainbow, in reference to the multitude of colours found among the nearly 300 species.

107. XERONEMATACEAE Poor-Knights-lily family

This family includes robust stemless, rhizomatous, tufted, evergreen perennial herbs. Rhizomes are short and upright, but hidden by the fibrous remains of old leaves. Iris-like, ensiform (unifacial) leaves are alternate, in a plane and overlapping (distichous), rigidly upright and sheathing at the base. Inflorescences are terminal, spikelike racemes that grow horizontally with the flowers pointing upwards. The peduncle has several sheathing bracts, and pedicels are subtended by floral bracts. Six red tepals are free, more or less equal in size, erect at first but reflexing and twisting downwards and persisting with the stamen filaments until the capsule ripens. Six stamens are longer than the tepals and have dorsifixed anthers opening by a longitudinal slit. The superior ovary is more or less stipitate (on a gynophore), constricted

Xeronema callistemon, Royal Botanic Gardens, Kew, UK [107]

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ASPARAGALES in the middle and trilocular. The style is also longer than the tepals and terete with a narrow stigma. The fruit is a triangular capsule that is broader below than above the equatorial constriction. It splits into three, but the valves usually only separate widely in the upper part. Distribution: This family is restricted to central New Caledonia and Poor Knights and Taranga Islands in northern New Zealand. Phylogeny and evolution: The genus has been variously placed in Asphodelaceae or Hemerocallidaceae (now a subfamily of Asphodelaceae), but molecular evidence has shown that it is the sister to the combined Amaryllidaceae, Asparagaceae and Asphodelaceae. The age of the stem group of Xeronemataceae is estimated to be c. 70 to 100 million years old. Genera and species: Xeronema includes two species: X. callistemon off New Zealand and X. moorei in New Caledonia. Etymology: Xeronema is derived from Greek ξηρός (xeros), dry, and νήμα (nema), a thread, in reference to the persistent filaments of the flowers.

108. ASPHODELACEAE Daylily family

A diverse family of clump-forming or rhizomatous perennial herbs, shrubs, vines or pachycaul branched or unbranched trees with anomalous secondary growth. Roots are usually succulent and sometimes thickened and tuberous, occasionally stilt-like. The leaves are held in a plane (distichous) or spirally arranged, herbaceous or succulent, or brittle, flat, V-shaped, swollen or terete,

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MONOCOTS

with parallel venation that may be obscure in succulent species; some have thickened resiniferous bases (Xanthorrhoea). Inflorescences are terminal variously branched panicles, racemes and cylindrical spikes or reduced to a single flower, rarely an umbel (Tricoryne), the peduncle is leafless or with (sometimes colourful) bracts. The bisexual flowers are actinomorphic or zygomorphic and composed of six free tepals that can be slightly fused into a tube at base, the whorls equal or the inner slightly larger than the outer whorl. The six stamens are free or some fused basally with the tepals. Anthers are basifixed or dorsifixed and open by pores or slits. The superior or semi-inferior ovary is uni- or trilocular and has a simple style at the apex, rarely gynobasic (Tricoryne), terminated by a small capitate stigma or a tuft of hairs. The fruit is a berry, nutlet or capsule that splits into three, exposing black seeds. Distribution: This widespread family is found in western South America, southern and central Europe, North Africa, Turkey east to temperate and tropical East Asia and south throughout the Middle East, Sub-Saharan Africa, Madagascar, Malesia, New Guinea, Australia, New Zealand and throughout the Pacific. Phylogeny and evolution: The crown group of Asphodelaceae is dated to c. 90 million years. Fossil pollen of Phormium is known from the Upper Miocene of New Zealand. Excremis and Pasithea represent independent migrations of the phormioid clade to South America. The three subfamilies have often been treated as independent families, but they share a number of characters. The family circumscription has been controversial and a three-family concept is preferred by some. However, if this is done, the daylily family is to be expanded with a number of Southern Hemisphere genera (e.g. former families Johnsoniaceae and Phormiaceae) making it morphologically just as diverse as a broader Asphodelaceae. Recognising Aloaceae, as has also often been advocated, would make Asphodelaceae non-monophyletic. The

large genus Aloë is not monophyletic in its traditional sense, Astroloba, Chortolirion, Gasteria and Haworthia being embedded, which resulted in the merger of Chortolirion with Aloë and the segregation of Aloidendron, Aloiampelos, Aristaloë, Gonialoë, Haworthiopsis, Kumara and Tulista. Many intergeneric hybrids are known, which makes one wonder if it is not better to treat Aloë in a broader sense and include Gasteria and Haworthia. Geitonoplesium has resupinate leaves, which resulted in an association of that genus with Alstroemeriaceae, but it is placed here on the basis of other characters. Many species produce copious nectar and are pollinated by birds, driving differences in flower structure among closely related taxa. Many know this family as Xanthorrhoeaceae as that name was used in APG III because this name had nomenclatural priority, but the name Asphodelaceae has been conserved by committee and is now the one to be applied to this family. Genera and species: A family of 39 genera with c. 1,200 species, subdivided into three subfamilies: Asphodeloideae – Aloë (536), Aloiampelos (10), Aloidendron (6), Aristaloë (1), Asphodeline (17), Asphodelus (17), Astroloba (7), Bulbine (77), Bulbinella (25), Eremurus (59), Gasteria (20), Gonialoë (3), Haworthia (149), Haworthiopsis (3), Kniphofia (71), Kumara (2), Trachyandra (57) and Tulista (2); Xanthorrhoeoideae – Xanthorrhoea (28); Hemerocallidoideae – Agrostocrinum (2), Arnocrinum (3), Caesia (13), Chamaescilla (3), Corynotheca (6), Dianella (41), Excremis (1), Geitonoplesium (1), Hemerocallis (19), Hensmania (3), Herpolirion (1), Hodgsoniola (1), Johnsonia (5), Pasithea (1), Phormium (2), Simethis (1), Stawellia (2), Stypandra (2), Thelionema (3) and Tricoryne (8). Uses: Dried leaf sap of aloes is used in a wide range of cosmetics, medicines and drinks. Aloë vera is cultivated for this purpose on a commercial scale, especially in the Caribbean, whereas A. ferox is mostly harvested from the wild in Africa. Young shoots and flower buds of daylilies, Hemerocallis, are often eaten

ASPARAGALES

MONOCOTS

Phormium cookianum, Royal Botanic Gardens, Kew, UK [108]

Geitonoplesium cymosum, National Botanic Gardens, Glasnevin, Ireland [108]

Hemerocallis fulva, Helsinki Botanical Garden, Finland [108]

Aloë macra, Réunion [108]

Kniphofia hirsuta, private garden, Kingston upon Thames, Surrey, UK [108]

Xanthorrhoea preissii, Mt Benia, Western Australia [108]

Asphodeline lutea, Greece [108]

Chamaescilla versicolor, Mt Benia, Western Australia [108]

Dianella revoluta, Royal Botanic Gardens, Kew, UK [108]

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ASPARAGALES

MONOCOTS

in Asia, although not all species are edible. Many cultivars and hybrids exist, and these are popular garden plants. New Zealand flax, Phormium tenax, was used to make clothes and ropes and planted commercially for this purpose, becoming problematic on oceanic islands like St Helena, where it was grown to supply twine to the UK post office. It is now mostly grown as an ornamental. Dianella leaves were used for similar purposes. Fruits of Dianella ensifolia are sometimes eaten and have been used as a cloth dye. Grass trees (Xanthorrhoea) were formerly harvested for their resin, which was made into varnish, lacquer and wood stains. Many are popular ornamental plants especially species of Aloë, Asphodeline, Bulbine, Eremurus, Gasteria, Haworthia and Kniphofia. Etymology: Asphodelus is a Latinised form of the Greek plant name ασφόδελος (asfodelos), a plant associated with the afterlife, and it was often associated in mythology with Persephone, who was depicted wearing a garland of asphodels as a reference to the underworld. Tulbaghia ludwigiana, Royal Botanic Gardens, Kew, UK [109]

Crinum purpurascens, Royal Botanic Gardens, Kew, UK [109]

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109. AMARYLLIDACEAE Onion family

This family includes perennial herbs with f leshy rhizomes or bulbs, enveloped by sheathing dry leaves or leaf bases. They usually grow terrestrially, but aquatics and rarely epiphytes also occur. The alternate, distichously arranged leaves are usually linear and filiform, sometimes lanceolate to ovate, flat, angular, round or swollen and hollow (fistular), sessile or petiolate, with sheaths closed at the base and parallel venation. Inflorescences are umbels (reduced helicoid cymes), sometimes reduced to a single flower, or forming a spike (Allium spicatum),

subtended by one or two (rarely more) spathelike bracts that cover the inflorescence in bud, sometimes with inner bracteoles. Bisexual flowers are actinomorphic or zygomorphic. There are usually six, sometimes three or five tepals, fused at least at the base, sometimes forming a tube. Scales or appendices between tepals and stamens sometimes form a corona (some Allium, Tulbaghia and some Leucocoryne). Outgrowth of the perigone may sometimes also form a corona (Narcissus). Functional stamens are usually six, sometimes two or three and the missing ones then often staminodial, or 18 or more (Gethyllis), the stamens adnate to the style in Strumaria. Filaments are inserted on the tepals, free from each other or fused, often with appendages or forming a corona (e.g. Hymenocallis, Hieronymiella). Anthers are dorsifixed or basifixed and open by longitudinal slits or by pores in Galanthus and Leucojum. The trilocular ovary is superior (Agapanthoideae and most Allioideae), semi-inferior (some Allium) or inferior (Amaryllidoideae) with three nectaries and a style at the the base

Amaryllis belladonna, Beth Chatto Agapanthus inapertus, private garden, Kingston upon Thames, Surrey, UK [109] Gardens, England, UK [109]

Speea humilis, Royal Botanic Gardens, Kew, UK [109]

Leucocoryne pauciflora, Royal Botanic Gardens, Kew, UK [109]

Proiphys cunninghamii, Australian National Botanic Gardens, Canberra [109]

Allium callimischon subsp. haematostictum, Royal Botanic Gardens, Kew, UK [109]

ASPARAGALES

MONOCOTS

(Allium) or at the apex of the ovary. The fruit is a capsule that splits in three, rarely indehiscent or a berry. Distribution: This is a cosmopolitan family. Agapanthoideae are restricted to South Africa. Allioideae are mostly found in the Northern Hemisphere, southern Africa and South America. Amaryllidoideae have their greatest phylogenetic diversity in southern Africa, from where lineages moved northwards through Africa into Eurasia and thence to the Americas and Australasia. Phylogeny and evolution: Amaryllidaceae are thought to have evolved c. 87 million years ago. South African Agapanthus is sister to the rest of the family and evolved c. 50 million years ago. Even though this genus has been placed in its own family, it shares the umbellate inflorescence that is covered by bracts in bud, representative for all members of this family, including ones with singleflowered inflorescences. Allioideae diversified in the Northern Hemisphere, from where southern Africa (Tulbaghieae) and South America (Gilliesieae) lineages originated. The bilaterally symmetrical flowers of Gilliesia, Miersia and Solaria are thought to mimic female insects. In Amaryllidoideae, the American species are sister to the Eurasian members, which suggests a so-called Boreotropical hypothesis, one in which the family entered the Americas through the boreal zones when these regions were much warmer than they are today. Similar as they may be in appearance, the South African Amaryllis is not directly related to South American Hippeastrum (which bears amaryllis as its common name). Generic delimitation needs some work especially among American Amaryllidoideae; genera in Hippeastreae are poorly circumscribed and require reclassification. To maintain Galanthus as separate from Leucojum, Acis was reinstated. Nectaroscordum belongs to Allium. This family was formerly known as Alliaceae (e.g. APG II), which had nomenclatural priority, but the name was rejected

by committee in favour of Amaryllidaceae, which is now the name to be used. Genera and species: This family includes 77 genera and c. 2,140 species, divided in three subfamilies: Amaryllidoideae (62 genera, c. 1,000 species) – Acis (9), Amaryllis (2), Ammocharis (7), Apodolirion (6), Boophone (2), Brunsvigia (9), Caliphruria (4), Calostemma (3), Cearanthes (1), Chlidanthus (4), Clinanthus (22), Clivia (6), Crinum (105), Crossyne (2), Cryptostephanus (3), Cyrtanthus (56), Eithea (1), Eucharis (17), Eucrosia (8), Eustephia (6), Galanthus (20), Gethyllis (30), Griffinia (21), Habranthus (83), Haemanthus (22), Hannonia (1), Hessea (13), Hieronymiella (8), Hippeastrum (91), Hymenocallis (65), Ismene (10), Lapiedra (1), Leptochiton (2), Leucojum (2), Lycoris (22), Mathieua (1), Namaquanula (2), Narcissus (c. 30), Nerine (25), Pamianthe (3), Pancratium (21), Paramongaia (2), Phaedranassa (9), Phycella (5), Placea (6), Plagiolirion (1), Proiphys (4), Pyrolirion (8), Rauhia (4), Rhodophiala (27), Scadoxus (9), Sprekelia (2), Stenomesson (16), Sternbergia (8), Strumaria (27), Tocantinia (1), Traubia (1), Ungernia (10), Urceolina (7), Vagaria (2), Worsleya (1) and Zephyranthes (87); Allioideae (14 genera, 1,134 species) – Allium (920), Gilliesia (7), Ipheion (3), Latace (2), Leucocoryne (48), Miersia (1), Nothoscordum (89), Prototulbaghia (1), Schickendantziella (1), Solaria (6), Speea (2), Trichlora (4), Tristagma (17) and Tulbaghia (27); Agapanthoideae – Agapanthus (7). Uses: Members of Allium has been used as vegetables or condiments since the Bronze Age. The onion, Allium cepa, is the most widely cultivated species. It is a cultigen, not known in the wild, but probably has its origin in Central Asia. Onions were such an important food that bulbs have been used as currency. A common variety of the onion is the shallot (A. cepa var. aggregatum, previously known as A. ascalonicum), which has a milder flavour and is often pickled. Leek (A. ampeloprasum) is another ancient vegetable and, with the daffodil (Narcissus pseudonarcissus), the symbol of Wales. Elephant garlic is probably close to the

wild ancestor of the leek. Another important crop is garlic (A. sativum), also with a 7,000year history of cultivation; it is important for food and human health. The first recorded cultivated onions, garlic and leeks were grown in Ancient Egypt. Other minor crops are chives (A. schoenoprasum), Welsh onion (A. fistulosum), garlic chives (A. tuberosum), Persian shallot (A. stipitatum) and scallion (A. chinense). Society garlic (Tulbaghia violacea) is also eaten and has the benefit of not making your breath smell as does garlic. Onion-scented Nothoscordum species are also sometimes used to flavour food. Species of Amaryllidoideae are poisonous but have been used in shamanic tradition to induce hallucinations and visions. Many genera are important in the bulb trade: Amaryllis, Allium, Crinum, Cyrtanthus, Galanthus, Hippeastrum, Hymenocallis, Ipheion, Ismene, Leucocoryne, Leucojum, Lycoris, Narcissus, Nerine, Sprekelia, Sternbergia and Zephyranthes. Agapanthus and Tulbaghia are popular garden perennials, and Clivia, Haemanthus, Eucharis and Scadoxus are frequent houseplants. Amaryllis (Hippeastrum) and narcissi (Narcissus) are important in the cut-flower industry. Some species of Nothoscordum are noxious weeds. Etymology: Amaryllis is the name of a shepherdess in Virgil’s Eclogues. It was probably derived from the Greek αμαρυσσό (amarysso), to sparkle.

110. ASPARAGACEAE Hyacinth family

This varied family includes perennial, annual, polycarpic or monocarpic, terrestrial and rarely epiphytic herbs, shrubs, trees and vines. Stems can form rhizomes, erect woody trunks

Plants of the World

171

ASPARAGALES

Yucca brevifolia, Joshua Tree National Park, California, USA [110]

MONOCOTS

Aphyllanthes monspeliensis, Spain [110]

Agave parryi, New Mexico (DZ) [110]

Asparagus plocamoides, Helsinki Botanical Garden, Finland [110]

Lomandra insularis, New Caledonia [110]

Dracaena reflexa var. angustifolia, Seychelles [110]

Thysanotus patersonii, Flinders Ranges, South Australia [110]

Theropogon pallidus, Royal Polygonatum odoratum, Finland [110] Botanic Gardens, Kew, UK [110]

Milla biflora, Royal Botanic Gardens, Kew, UK [110]

Bessera elegans, private garden Kingston upon Thames, Surrey, UK [110]

172

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Ledebouria cooperi, private garden Kingston upon Thames, Surrey, UK [110]

Ornithogalum nutans, Royal Eucomis comosa, private garden Botanic Gardens, Kew, UK [110] Kingston upon Thames, Surrey, UK [110]

ASPARAGALES

MONOCOTS

(with secondary growth), tunicate bulbs, corms and tubers, or stems can be scandent. Roots are often fleshy but can be fibrous in some species. Alternate, sometimes opposite or verticillate, leaves are clumped, in a rosette or spread along the stem and are usually spirally arranged, sometimes in a plane (distichous), or singular, sometimes lacking in the adult stage (Bowiea, Drimia), sessile or petiolate, herbacous or succulent or rigid and fibrous, sometimes the leaves reduced to scales (Aphyllanthes, Asparagus). Blades are linear, lanceolate, elliptic or ovate and the venation is parallel, sometimes with parallel or reticulate cross-veins, with the bases often clasping the stem, sheathing or not. Bases sometimes form a pseudostem, and leaf tips are occasionally cirrhose. In Asparagoideae and Nolinoideae, stems are sometimes broadened and resemble leaves (phylloclades; e.g. in Asparagus, Danaë, Ruscus and Semele). Flowering stems are bracteate, often scapose, sometimes underground or absent, the inflorescences terminal or axillary panicles, spikes and racemes, sometimes reduced to a single flower, sometimes umbel-like (Brodiaeoideae, Leucocrinum, some Dracaena), fascicled or capitate (Aphyllanthes), the bracts usually many and not enclosing buds. The bisexual, sometimes unisexual, flowers are actinomorphic or zygomorphic, usually subtended by one to several bracts. The six (sometimes four or five) tepals are petallike and free or united into a long or short tube or cup. The six (sometimes three, four, eight, ten or 12) stamens have free filaments that are sometimes fused with the perianth at the base. Stamens are rudimentary in female flowers of dioecious species, and staminodial when a whorl of stamens is missing. Anthers are dorsifixed or basifixed and open by longitudinal slits. The superior to inferior ovary is composed of three fused carpels, unior trilocular, rarely stalked (with a gynophore in Chlorophytum and some Brodiaeoideae) and topped by a single style with a capitate, trilobed or three-branched stigma, or the three styles free (Yucca). The fruit is usually a loculicidal, sometimes septicidal, capsule or

a berry, sometimes a three-winged samara or a three-ribbed nut. Distribution: Asparagaceae have a nearly cosmopolitan distribution but are absent from the coldest regions in the Arctic and Antarctic and have not been found in eastern Amazonia or the Sahara and Gobi Deserts. Aphyllanthoideae are restricted to the western Mediterranean. Agavoideae occur in the Americas from southern Canada to Patagonia, throughout central and southern Europe, Sub-Saharan Africa, South and East Asia and Malesia. Brodiaeoideae are restricted to western North America, Mexico and Guatemala. Scilloideae occur in western South America, Europe, North and Sub-Saharan Africa, Madagascar, western, central and southern Asia, China, Korea and Japan. Lomandroideae are restricted to Southeast Asia and Australasia. Asparagoideae are widespread across the Old World and have an isolated population in Mexico (Hemiphylacus). Nolinoideae are spread across North America, Mesoamerica, Europe, North, West and Central Asia, Sub-Saharan Africa and northern Australia. Phylogeny and evolution: Circumscription of this group of plants has varied greatly in the past. Most subfamilies mentioned below were known at some point as separate families: Agavaceae, Anemarrhenaceae, Anthericaceae, Behniaceae, Herreriaceae and Hostaceae (now all Agavoideae), Convallariaceae, Dracaenaceae, Eriospermaceae, Nolinaceae and Ruscaceae (now all Nolinoideae), Hyacinthaceae (now Scilloideae) and Themidaceae (now Brodiaeoideae). The seven subfamilies together form a well-supported clade. Asparagoideae and Lomandroideae are sister to the rest. The placement of Aphyllanthes has been problematic. Although here placed in Nolinoideae, Eriospermum has also been found as sister to Asparagoideae. Classification of Nolinoideae needs further study. Brodiaeoideae are similar to Allioideae of Amaryllidaceae (where they were

previously placed), but differ from those in having corms and three or more bracts that do not completely enclose the developing umbellate inflorescence. Fossils of Protoyucca are known from the Eocene of Nevada and are remarkably similar to modern Yucca. Nolinoideae-like fossils (Palaeocene Maianthemophyllum and Eocene Soleredera) are known from Canada. Fossil Paracordyline is known from Oligocene and Eocene deposits in Australia and Kerguelen. Pollen of Cordyline is known from the Miocene onwards. Divergence within Asparagaceae (crown group) is dated to have begun c. 89 million years ago. New World Oziroë diverged from the remaining Scilloideae (Old World) c. 28 million years ago. The tree-like habit frequent in Asparagaceae has evolved independently several times in Agavoideae (Yucca), Lomandroideae (Cordyline) and Nolinoideae (Beaucarnea, Dasylirion, Dracaena, Nolina). Some genera will need to be recircumscribed, pending further study. Beaucarnea is embedded in Nolina, and Sansevieria and Dracaena have also been united, but these changes are found to be somewhat controversial, especially in horticultural circles, and have not yet been adopted by the World Checklist of Selected Plant Families, which is why those are maintained here. Polianthes and Manfreda are merged with Agave, Smilacina has been merged with Maianthemum and Urginea is now part of Drimia. The genera Scilla and Muscari were also found to be polyphyletic, resulting in the acceptance of Alrawia, Fessia, Hyacinthella, Hyacinthoides, Leopoldia, Mer willa, Prospero, Pseudomuscari, Pseudoprospero, Resnova, Schizocarphus and Zagrosia in addition to Scilla, Muscari, Bellevalia, Puschkinia and Hyacinthus. Chionodoxa is part of Scilla sensu stricto. Nevertheless, generic delimitation in Scilloideae is still not yet well studied and is likely to undergo further change. Genera and species: A large family with 118 genera and c. 3,220 species divided in

Plants of the World

173

ASPARAGALES seven subfamilies: Aphyllanthoideae – only Aphyllanthes (1); Agavoideae – Agave (252), Anemarrhena (1), Anthericum (7), Behnia (1), Beschorneria (8), Camassia (6), Chlorogalum (5), Chlorophytum (193), Clara (3), Diamena (1), Diora (1), Diuranthera (4), Echeandia (80), Eremocrinum (1), Furcraea (23), Hagenbachia (6), Hastingsia (4), Herreria (8), Herreriopsis (1), Hesperaloë (8), Hesperocallis (1), Hesperoyucca (2), Hosta (23), Leucocrinum (1), Paradisea (2), Schoenolirion (3), Trihesperus (2) and Yucca (49); Brodiaeoideae – Androstephium (2), Bessera (3), Bloomeria (3), Brodiaea (17), Dandya (4), Dichelostemma (5), Jaimehintonia (1), Milla (10), Muilla (3), Petronymphe (1), Triteleia (15) and Triteleiopsis (1); Scilloideae – Albuca (160), Alrawia (2), Barnardia (2), Bellevalia (65), Bowiea (1), Brimeura (3), Daubenya (8), Dipcadi (41), Drimia (106), Drimiopsis (14), Eucomis (11), Fessia (11), Fusifilum (15), Hyacinthella (17), Hyacinthoides (11), Hyacinthus (3), Lachenalia (132), Ledebouria (55), Leopoldia (12), Massonia (14), Merwilla (3), Muscari (44), Namophila (1), Ornithogalum (185), Oziroë (5), Prospero (15), Pseudogaltonia (1), Pseudomuscari (7), Pseudoprospero (1), Puschkinia (2), Resnova (5), Schizocarphus (1), Scilla (81), Spetaea (1), Veltheimia (2) and Zagrosia (1); Asparagoideae – Asparagus (212) and Hemiphylacus (5); Lomandroideae – Acanthocarpus (7), Arthropodium (9), Chamaexeros (4), Cordyline (24), Dichopogon (5), Eustrephus (1), Laxmannia (14), Lomandra (51), Murchisonia (2), Romnalda (3), Sowerbaea (5), Thysanotus (50), Trichopetalum (2) and Xerolirion (1); Nolinoideae – Aspidistra (101), Beaucarnea (11), Comospermum (1), Convallaria (3), Danaë (1), Dasylirion (22), Disporopsis (7), Dracaena (112), Eriospermum (112), Heteropolygonatum (6), Liriope (6), Maianthemum (38), Nolina (28), Ophiopogon (67), Peliosanthes (23), Polygonatum (65), Reineckea (1), Rohdea (17), Ruscus (6), Sansevieria (69), Semele (3), Speirantha (1), Theropogon (1) and Tupistra (21).

174

Christenhusz, Fay & Chase

MONOCOTS

Uses: Garden asparagus, sometimes colloquially called sparrowgrass, (Asparagus officinalis) has been eaten since classical times and was depicted on an Egyptian frieze from 3000 BC. Other Asparagus species are harvested from the wild and eaten in spring in the Mediterranean and Asia. Prussian or Bath asparagus, young Ornithogalum pyrenaicum shoots, are also consumed sometimes. Muscari comosum bulbs are pickled in Greece. Quamash, Camassia was eaten by native North American tribes. Agave species have been used extensively by North American native peoples. Species like henequen (A. fourcroydes) and sisal (A. sisalana) are cultivated for their fibre, sometimes on a large scale. Agave tequilana is used to make alcoholic beverages like tequila. Mescal is a similar beverage made from A. americana, and sotol is made of roasted tubers of Dasylirion. The syrup made from A. tequilana and A. salmiana is marketed as agave nectar, which is a sweetener high in fructose. Furcraea foetida is also cultivated for its fibre that is similar to sisal. Plants are prolific, and some produce young plants in the inflorescence, making them problematic invasives. In the Pacific and Australasia, fibre of Cordyline and Lomandra is used extensively. Cordyline berries are used in Polynesian tattoo ink. Roots, shoots, leaves and inflorescences of species of Leucocrinum and Chlorophytum are eaten by indigenous peoples in North America and Africa, respectively. Flowers and buds of Convallaria keiskei and Tupistra nutans, young shoots and fruits of various Maianthemum species and rhizomes of some Polygonatum, Ophiopogon and Liriope species are eaten in Asia, and Cordyline was eaten in New Zealand and Indonesia. Leaves of Hosta are cooked and eaten in Korea and Japan. Bunches of Ruscus aculeatus (butcher’s broom) were cut to make brushes for cleaning the floor of butcher’s shops. Many species are popular garden or namentals and houseplants: e.g. Anemarrhena (zhi mu), Anthericum (St Bernard’s lily), Aspidistra (cast-iron plant),

Beschorneria, Beaucarnea (ponytail palm), Chlorophytum (spider plant), Convallaria (lily of the valley), Cordyline (cabbage tree), Dasylirion (desert spoon), Dracaena (dragon tree), Hosta (plantain lily), Ledebouria (silver squill), Liriope (monkey grass), Lomandra (mat-rush), Maianthemum (may lily), Ophiopogon (lilyturf), Polygonatum (Solomon’s seal), Sansevieria (mother-inlaw’s tongue) and Yucca (yuccapalm), and a good number are grown on a large scale for the f lower bulb industry: Camassia (quamash), Bellevalia, Bessera (coral drops), Brimeura (amethyst hyacinth), Brodiaea (cluster lily), Dichelostemma (blue dicks), Eucomis (pineapple lily), Hyacinthoides (bluebells), Hyacinthus (hyacinth), Lachenalia (Cape cowslip), Muscari (grape hyacinth), Ornithogalum (star-of-Bethlehem), Puschkinia (striped squill), Scilla (squill), Triteleia (triplet lily) and Veltheimia (elephant’s eye). Some species are used frequently in the cut-flower industry, e.g. Agave polianthes (tuberose), Convallaria majalis (lily-of-the-valley), Hyacinthus orientalis (hyacinth), Ornithogalum arabicum, O. dubium, O. saundersiae and O. thyrsoides, often because of their strong fragrances that are also used in the perfume industry. Stems of Danaë racemosa and the asparagus fern (Asparagus setaceus) are much used by florists. Dracaena reflexa var. angustifolia, usually sold as ‘D. marginata’, takes second place (after Ficus benjamini, Moraceae) as the most common indoor foliage plant in Europe and North America. Longest name: Ornithogalum adseptentrionesvergentulum, a species from the South African karroo, has the longest plant species epithet with 38 letters, yet it is a tiny plant species, flowering at just under 3 cm tall. A label with its name has to be taller than the plant. Etymology: Asparagus is the classical Latin name for the spring vegetable, which is derived from Ancient Persian asparag, a shoot or sprout.

ARECALES

COMMELINIDS The remainder of monocots comprise what are known as the “commelinids”, a clade of monocots with cell-wall ferulates (that fluoresce), Strelitzia-type epicuticular wax and an endosperm with abundant starch, although Arecaceae lack the last (most likely a secondary loss). Some authors have recognised this clade formally, often as the superorder Commelinanae, but they are not formally named in APG IV (2016).

ARECALES This order is composed of two families, Arecaceae and Dasypogonaceae, the latter unplaced until recently. The two families form trees in a similar manner and form with reasonable support a clade. It is noteworthy that the area where Dasypogonaceae are found in Western Australia lacks native palms, even though the climate is perfectly suitable for Arecaceae.

111. DASYPOGONACEAE Saviour-grass family

This is a family of shrubby and arborescent perennials. Stems are woody, creeping or erect, and when erect are covered in roots growing down from the crown to the base (Kingia). Leaves are spirally arranged, usually furrowed on the upper side, and can be short and broad or elongate and grasslike. Flowers can be solitary or in dense globular heads. The bisexual flowers have six Dasypogon obliquifolius, Mt Benia, Western Australia [111]

persistent petals in two similar whorls, which are variably fused or free. The six stamens are usually attached to the petal base, and anthers are basifixed or dorsifixed with two thecae that open by two slits or pores. The superior ovary is tri- or unilocular, the single style with a capitate or trilobed stigma. Fruits are indehiscent, rarely explosive capsules, enclosed by persistent petals. Distribution: Southwestern Australia houses nearly all the diversity of this family. A single species of Calectasia occurs disjunctly in western Victoria and adjacent South Australia. Phylogeny and evolution: The family is estimated to have originated c. 100 million years ago, but they have no fossil record. They are distantly related to Arecales. Members of the family were previously associated Calectasia grandiflora, Perth, Western Australia [111]

with other tree-forming monocots, but this was based on superficial resemblance: Xanthorrhoea for example, has (anomalous) secondary growth, whereas all growth in Dasypogonaceae, as in palms, is primary, even when woody as in Kingia. Genera and species: This small family includes four genera and c. 17 species: Baxteria (1), Calectasia (11), Dasypogon (3) and Kingia (2). Uses: Although species have ornamental potential, they grow slowly and the seeds are difficult to germinate. Leaf bases and other parts of Baxteria smell of rotten flesh, and this may be connected with attraction of pollinators. Etymology: Dasypogon is composed of Greek δασυς (dasys), hairy, and πωγων (pogon), beard.

Kingia australis, Mt Benia, Western Australia [111]

Plants of the World

175

ARECALES

Lodoicea maldivica, female tree, Praslin, Seychelles [112]

Lodoicea maldivica, male inflorescence, Praslin, Seychelles [112]

Nypa fruticans, Singapore (KH) [112]

Nypa fruticans, inflorescence, Singapore (KH) [112]

Chamaerops humilis, Royal Botanic Gardens, Kew, UK [112]

176

MONOCOTS

Christenhusz, Fay & Chase

Cyrtostachys renda, Singapore Botanical Garden [112]

Washingtonia filifera, Andreas Canyon, Palm Springs, California, USA [112]

Bismarckia nobilis, cultivated in Guayaquil, Ecuador [112]

Calamus longipinna, Royal Botanic Gardens, Kew, UK [112]

Ceroxylon quindiuense, San Francisco Botanical Garden, USA [112]

ARECALES

MONOCOTS

112. ARECACEAE Palm family

Palms include trees and shrubs with single or clustered, slender to thick, climbing, creeping and erect subterranean to tall, usually unbranched (rarely forking), woody stems that are armed with spines or not and often have clear leaf scars on the bark. They do not produce secondary growth, and although woody their trunks are formed solely through primary growth. Trunks are sometimes supported by stilt roots, and sometimes roots are modified into spines. Leaves are usually arranged in a spiral at the tip of the stem, sometimes in one plane (distichous) or three-ranked (tristichous). Petioles are sheathing, with the sheath initially tubular, often splitting later, sometimes with a ligule-like appendage. Above the sheath, petioles are armed with spines or not, often with a hastula (a small outgrowth between the petiole and the base of the leaf blade). Blades are entire and pinnately or palmately veined and costapalmately or pinnately divided, often formed by elongation of the rachis ripping the blades into leaflets, sometimes bifid (split in twos). Leaves are plicately folded in bud, the segments V- or Λ-shaped in cross-section. In some species, apices of the leaves are modified into a climbing whip, with the final leaflets replaced by spines. Inflorescences are solitary or multiple, compound or simple, axillary spikes, surrounded by one or more large bracts (prophylls), and peduncular bracts are absent to many. Flowers are unisexual or bisexual, similar or dimorphic, solitary or in cincinni. Sepals are usually three (sometimes two or more than three), free or variously fused. Petals are usually as many as sepals, free or fused. The usually six stamens (sometimes three or more numerous, up to c. 1,000) have erect filaments that are free or variously fused

with each other or with petals. Staminodes are strongly reduced and tooth-like or well developed, rarely absent. Ovaries are superior and have (1–)3(–4) fused carpels, with or without styles, the stigmas erect or curved backwards. Pistillodes can be present or absent in male flowers and are variable in shape and size when present. Fruits are usually singleseeded (sometimes with two to ten seeds), ranging from small to large (then often called ‘coconuts’), the skin smooth, hairy, prickly, warty or covered in overlapping scales, the mesocarp dry, fibrous or fleshy and the endocarp thin or woody, with one to three or without pores. Even though it was often previously assumed that all palms are windpollinated, it has been shown that numerous species are visited frequently and pollinated by insects, especially beetles, but also by bees, ants and flies. Distribution: Palms are pantropical and most diverse in montane rainforests in the tropics, but also in desert areas. They also extend into subtropical and temperate regions of North and South America, southern Europe, temperate Asia and New Zealand. Phylogeny and evolution: Palms were previously often associated with other ‘palmlike’ monocots such as Cyclanthaceae and Pandanaceae, but DNA analyses have shown them to be members of the commelinid clade, closest to Dasypogonaceae in the Arecales. They are divided into five subfamilies. Nypoideae have the oldest fossil record. Coryphoideae are considered the least specialised of palms and consist mostly of palmate and costapalmate genera. Calamoideae are distinguished by their scaled fruits that resemble pangolin skin. Some genera have been reorganised recently, notably Calamus includes the genera Daemonorops, Ceratolobus and Pogonotium. Genera and species: This is a family of 195 genera in five subfamilies and c. 2,400 species: Calamoideae – Calamus (c. 500), Eleiodoxa (1), Eremospatha (11), Eugeissona (6), Korthalsia (27), Laccosperma (6), Lepidocaryum (1), Mauritia (2), Mauritiella (4),

Metroxylon (7), Myrialepis (1), Oncocalamus (5), Pigafetta (2), Plectocomia (15), Plectocomiopsis (6), Raphia (20), Retispatha (1) and Salacca (22); Nypoideae – Nypa (1); Coryphoideae – Acoelorrhaphe (1), Arenga (24), Bismarckia (1), Borassodendron (2), Borassus (5), Brahea (11), Caryota (14), Chamaerops (1), Chelyocarpus (4), Chuniophoenix (3), Coccothrinax (51), Colpothrinax (3), Copernicia (22), Corypha (5), Cryosophila (10), Guihaia (2), Hemithrinax (3), Hyphaene (8), Itaya (1), Johannesteijsmannia (4), Kerriodoxa (1), Lanonia (8), Latania (3), Leucothrinax (1), Licuala (162), Livistona (28), Lodoicea (1), Maxburretia (3), Medemia (1), Nannorrhops (1), Phoenix (14), Pholidocarpus (6), Pritchardia (28), Rhapidophyllum (1), Rhapis (11), Sabal (14), Sabinaria (1), Saribus (9), Satranala (1), Schippia (1), Serenoa (1), Tahina (1), Thrinax (3), Trachycarpus (9), Trithrinax (4), Wallichia (8), Washingtonia (2) and Zombia (1); Ceroxyloideae – Ammandra (1), Aphandra (1), Ceroxylon (12), Juania (1), Oraniopsis (1), Phytelephas (6), Pseudophoenix (4) and Ravenea (20); Arecoideae – Acanthophoenix (3), Acrocomia (8), Actinokentia (2), Actinorhytis (1), Adonidia (2), Aiphanes (29), Allagoptera (5), Archontophoenix (6), Areca (45), Asterogyne (5), Astrocaryum (37), Attalea (76), Bactris (77), Balaka (9), Barcella (1), Basselinia (14), Beccariophoenix (2), Bentinckia (2), Brassiophoenix (2), Burretiokentia (5), Butia (22), Calyptrocalyx (26), Calyptrogyne (17), Calyptronoma (3), Carpentaria (1), Carpoxylon (1), Chamaedorea (106), Chambeyronia (2), Clinosperma (4), Clinostigma (11), Cocos (1), Cyphokentia (2), Cyphophoenix (4), Cyphosperma (5), Cyrtostachys (7), Deckenia (1), Desmoncus (24), Dictyocaryum (3), Dictyosperma (1), Dransfieldia (1), Drymophloeus (3), Dypsis (162), Elaeis (2), Euterpe (7), Gaussia (5), Geonoma (68), Hedyscepe (1), Heterospathe (41), Howea (2), Hydriastele (49), Hyophorbe (5), Hyospathe (4), Iguanura (32), Iriartea (1), Iriartella (2), Jailoloa (1), Jubaea (1), Jubaeopsis (1), Kentiopsis (4), Laccospadix (1), Lemurophoenix (1), Leopoldinia (2), Lepidorrhachis (1), Linospadix (7), Loxococcus (1), Lytocaryum (4), Manicaria (2), Manjekia (1), Marojejya (2), Masoala (2), Nenga (5),

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ARECALES Neonicholsonia (1), Neoveitchia (2), Nephrosperma (1), Normanbya (1), Oenocarpus (9), Oncosperma (5), Orania (28), Parajubaea (3), Pinanga (138), Pelagodoxa (1), Pholidostachys (8), Phoenicophorium (1), Physokentia (7), Podococcus (2), Ponapea (4), Prestoea (10), Ptychococcus (2), Ptychosperma (30), Reinhardtia (6), Rhopaloblaste (6), Rhopalostylis (2), Roscheria (1), Roystonea (10), Satakentia (1), Sclerosperma (3), Socratea (5), Solfia (1), Sommieria (1), Syagrus (53), Synechanthus (2), Tectiphiala (1), Veitchia (11), Verschaffeltia (1), Voanioala (1), Welfia (1), Wallaceodoxa (1), Wendlandiella (1), Wettinia (21) and Wodyetia (1). Uses: Palms are among the most useful of plant families. Man evolved in tropical ecosystems, and palms were certainly a major factor in allowing Homo sapiens to have easy access to plant products to be used for food, shelter, clothes, tools, ropes, drugs and weapons. Even though there was a great diversity of plants available to mankind, palms had a primary role and have been a dominant factor in the development of human culture ever since. Fruit: there are numerous species of which fruit or seed is consumed, especially coconut, Cocos nucifera, date, Phoenix dactylifera, and snake palm, Salacca zalacca, being currently of major economic importance. Other species with edible fruits cultivated as minor crops are seashore palm (Allagoptera arenaria), tucum (Astrocaryum vulgare), peach palm (Bactris gasipaes), lontar palm (Borassus flabellifer), Guadalupe palm (Brahea edulis), jelly palms (Butia capitata, B. yatay), lawyer vines (Calamus spp.), carnauba palm (Copernicia prunifera), triangle palm (Dypsis decaryi), acai (Euterpe oleracea, E. precatoria), doum palm (Hyphaene thebaica), Chilean wine palm (Jubaea chilensis), coco-de-mer (Lodoicea maldivica), moriche palm (Mauritia flexuosa), mangrove palm (Nypa fruticans), bacaba (Oenocarpus bacaba), palmetto (Sabal spp.), queen palm (Syagrus romanzoffiana) and many other species. Coconut was named in the 16th century for resemblance of the seed with its three holes to a skull, ‘coco’ meaning head in Spanish.

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Of Indo-Pacific origin, coconuts were valued throughout that region and soon spread to most tropical islands and continents. Because the seeds float, they rapidly colonised new shores, and even wash ashore occasionally on beaches in Europe. Coconuts were domesticated in early times and selected for meatiness of seeds and thinner shells. They were already known in the American Pacific before European discovery of the continents; however, they were only introduced to the Caribbean after the 1500s. Seeds yield oil used in food. The meaty part of coconuts is eaten fresh or desiccated, used as a spice in cooking or for production of coconut milk. Coconut can also be dried, fried, added to granola and other breakfast cereals and chocolate bars etc. The embryonic fluid is tapped, and because coconut water is isotonic, it is a refreshing drink. Date palms (Phoenix dactylifera) have been cultivated since ancient times throughout the Middle East and North Africa. Dates have a high sugar content and are a valued commodity in desert climates, where they form an easily transportable staple food for desert caravans. They are not known in the wild and may be of hybrid origin. Beverages: palm wine or toddy is a fermented drink made from the sap of a variety of palm species, especially Borassus spp., Caryota urens, Cocos nucifera, Elaeis guineensis, Hyphaene coriacea, Jubaea chilensis, Phoenix sylvestris and Raphia spp. Vegetable: terminal buds of some palms are harvested and eaten as ‘cabbage’ or ‘palm heart’, but this is not sustainable in most cases and has resulted in many species being threatened. Palm cabbage is known to be or has been harvested from Acanthophoenix, Bactris, Cocos, Deckenia, Euterpe, Geonoma, Prestoea, Roystonea and Sabal, of which clonal palms like Euterpe edulis and Prestoea acuminata should be preferred, because if carried out in moderation harvesting does not kill the palm. Canned palm heart is often harvested from plantations of Bactris gasipaes, grown for this purpose in South America. Oil: African oil palm, Elaeis guineensis, is of major commercial value and used in many processed food products and as a biofuel.

It has replaced vast stands of rainforest. Products containing palm oil are therefore ecologically unsound, and consumers should try to avoid them. American oil palm (E. oleifera), Acrocomia and, of course, coconut (Cocos nucifera) are also used for oil, the last now heralded as a superfood. Wax: several palm species yield a valuable wax. Carnauba wax, harvested from the leaf coating of Copernicia prunifera, is used to produce a glossy finish in car wax, shoe polish, dental floss, candy, furniture and floor wax, paper coating, cosmetics etc. Wax of Andean wax palm (Ceroxylon quindiuense) is formed at the base of the leaf sheaths around the trunk apex. It was threatened with extinction because the wax was used to make candles, but it is now rarely used for this purpose. Starch: sago is starch extracted from the spongy pith of several palm species, most notably Metroxylon sagu, M. amicarum and M. salomonense. It is the major staple food for tribes in New Guinea and the Moluku Islands. It is also cultivated and exported as sago flour. Rotten trunks of palms may house large palm weevil larvae (Rhynchophorus palmarum), which are considered a delicacy called ‘suri’ by local people in Amazonia. Drugs: seeds of betel nut (Areca catechu) are chewed with leaves or inflorescences of Piper betle (Piperaceae), lime and other ingredients. They contain an alkaloid, arecaine, that acts as a mild narcotic. Fruits are also used as a source of tannin for dyeing and in traditional medicine. Betel nut is commonly cultivated in the Old World tropics, sometimes in larger plantations but usually on a smaller scale. Actinorhytis calapparia is chewed as a betel substitute. Saw palmetto (Serenoa repens) is used in the treatment of prostate problems. Handicrafts: many species are used for their fibre, especially in handicrafts, rope, mats and loin cloths. Economically, the most important is rattan, mostly made from Calamus rotang and other climbing species (often called lawyer vines because they often have fish-hook spines that snag clothing and follow you around). Rattan makes climbing stems of over 10 m long, which are flexible and have an even thickness. They are therefore useful for woven-furniture making, basketry

COMMELINALES

MONOCOTS

and even umbrellas. Raphia produces raffia fibre, which is used for textiles, mats, ropes, shoes, natural string and garden ties that are often used for wrapping grafts. Giant leaves of Attalea were used for roofing by Mayan tribes, and many species of this and other genera are still commonly used for thatch. Dransfieldia is used to make harpoons. Seeds of Attalea maripa have been found in 9,000-year old archaeological sites in Colombia. Phytelephas produces ‘vegetable ivory’, hard seeds that can be carved into beautiful ornaments. Seeds of some Calamus species are polished and crafted into prayer beads. Ornamental: palms are gracious plants and have an association with the tropics, where they are commonly planted as ornamentals. Tropical beaches are usually adorned with coconut palms, and royal palms (Roystonea regia) are an all-time favourite for lining avenues. Several species are common as house plants in the temperate zones, especially species of Howea, Dypsis, Rhapis and Chamaedorea. In mild temperate

gardens, cold-tolerant species such as Brahea armata, Butia capitata, Chamaerops humilis, Jubaea chilensis, Livistona chinensis, Nannorhops ritchieana, Parajubaea torallyi, Phoenix canariensis, Rhapidophyllum hystrix, Sabal palmetto, Syagrus romanzoffiana, Trachycarpus fortunei, T. takil, T. wagnerianus, Washingtonia filifera and W. robusta are planted to provide a ‘tropical’ look to the garden. Records: Arecaceae excel in size. Lodoicea maldivica, the coco-de-mer, produces the largest seeds of any angiosperm, weighing up to 30 kg. Corypha umbraculifera produces the largest inflorescence of any plant, which can be 7.5 m long and bear around 10 million flowers. With climbing stems of c. 200 m long, Calamus manan produces the longest stems of any angiosperm, and because palms can be hundreds of years old and have no secondary thickening, they also have the oldest vessels of any vascular plants. Seeds of some species can be viable for hundreds of years,

and germination experiments on the extinct Easter Island palm (Paschalococos) are currently been trialled. A seed of a date palm (Phoenix dactylifera) found in a 2,000-yearold tomb in Israel has been germinated and is growing well. With 19 letters, Johannesteijsmannia is one of the longest plant genus names, although the record appears to be Pseudoblepharispermum (Asteraceae). The largest leaf of any plant is also grown by a palm: Raphia regalis has leaves measuring 25.11 × 3.00 m, the largest in length, albeit divided into hundreds of leaflets. This record may be contested by the vining leaves of Salpichlaena volubilis (Aspleniaceae), as they have indeterminate growth and climb into the canopy of the forest, but actual measurements of those climbing leaves are wanting and therefore Raphia regalis remains the world record holder. Etymology: Areca is a Latinised form of the common name for betel nuts in Malabar, India.

COMMELINALES Families 113 to 117 form the order Commelinales. This order diversified c. 110 million years ago.

113. HANGUANACEAE Susum family

These are terrestrial and aquatic, perennial, unisexual herbs that, when young, are covered with branched hairs. Stems are erect, but form creeping or floating stolons. Leaves are spirally arranged with clasping, opensheathing bases that gradually form a petiole topped by a simple, lanceolate to linear leaf blade. Venation is parallel with a prominent

midvein and many tertiary crossveins, and blades are rolled up in bud. Inflorescences are terminal and composed of spikelets organised in a panicle or in whorls. The sessile flowers are radially symmetrical and have six bractlike petals in two whorls, the outer ones small and basally connate, the inner ones larger and hooded. Male flowers have six stamens that have thin filaments, broadened at the base, and anthers with two thecae opening by longitudinal slits. Stamens surround a disc-like structure that envelops a rudimentary ovary. Female flowers have six staminodes, often minute, that surround a superior trilocular ovary with a sessile stigma. Fruits are berries with one or three bowl-shaped seeds. Distribution: This family occurs from Sri Lanka to Southeast Asia through Malesia and the Philippines. It extends into Micronesia

up to Palau and south into New Guinea and northern Australia. Hanguana grows in humid forests in swamps and lakes and along rivers. It may form dominant stands, suppressing other vegetation, and may even form floating islands. Phylogeny and evolution: Relationships of Hanguana were considered puzzling in the past. They share some morphological similarities with Asteliaceae and Zingiberales, but molecular evidence placed Hanguana firmly in Commelinales. Hanguana was previously associated with Flagellariaceae, but it was shown to differ from Poales in many anatomical characters. Its position within Commelinales is still uncertain, but it may be sister to Commelinaceae.

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COMMELINALES

Hanguana anthelminthica, flower detail, Singapore Botanical Garden [113]

Hanguana anthelminthica, Singapore Botanical Garden [113]

Hanguana rubinea, Singapore (MN) [113]

Genera and species: The single genus Hanguana consists of c. 13 species, possibly more.

it that lacks ligules or stipules. The blade is simple, often somewhat fleshy and has an entire margin and parallel venation. Flowers are formed on cymose branches (cincinni), which are then part of panicles or thyrses, axillary or terminally. Cincinni are often enclosed by a leafy bract (spathe). Flowers are radially or laterally symmetical and usually bisexual, although separate male or female flowers also occur, but usually in combination with bisexual flowers. The three sepals are free or fused and equal or unequal in size and can be sepaloid or petaloid. The three petals are all of the same size or one reduced and are free or basally fused and sometimes clawed. The six stamens occur in two whorls, all fertile or two, three or four staminodial and reduced or lacking. Filaments are glabrous or hairy with beaded or simple hairs, the anthers opening by slits, rarely by pores. The superior ovary is bi- or trilocular with a terminal style. Fruits are dehiscent capsules, fleshy indehiscent capsules or berries.

stomata and pollen anatomy rather than flower structure. Subfamily Cartonematoideae are sister to the remainder of the family and have previously been placed in a separate family, based mainly on anatomical characters. Commelinaceae are most likely sister to Hanguanaceae, from which they diverged c. 89 million years ago; together this pair is sister to the remainder of families in the order.

Uses: The aquatic Hanguana anthelminthica has edible stems, although it is rarely consumed. Etymology: ‘Hanguan kassintu’ is the local name used in the Sunda Islands (Indonesia) for this genus, which was Latinised to name the genus.

114. COMMELINACEAE Spiderwort family

Perennial and annual, usually terrestrial, herbs make up this family. They have fleshy stems that often root from the swollen nodes and may have tuberous roots, especially in temperate species. Leaves are placed alternately along stems, sometimes clustered into false whorls; they are sheathing at the base with the closed sheath enveloping part of the internode above 180

MONOCOTS

Christenhusz, Fay & Chase

Distribution: They occur pantropically, extending into temperate North America and East Asia. Phylogeny and evolution: Previously the family was subdivided into two groups with zygomorphic and actinomorphic flowers. This division still stands in subfamily Commelinoideae, although it is based on

Genera and species: This family has 41 genera and 731 species in two subfamilies: Cartonematoideae – Cartonema (7), Triceratella (1); Commelinoideae – Aëtheolirion (1), Amischotolype (23), Aneilema (65), Anthericopsis (1), Belosynapsis (6), Buforrestia (3), Callisia (20), Cochliostema (2), Coleotrype (10), Commelina (198), Cyanotis (49), Dichorisandra (47), Dictyospermum (5), Elasis (1), Floscopa (21), Geogenanthus (3), Gibasis (14), Gibasoides (1), Matudanthus (1), Murdannia (55), Palisota (25), Plowmanianthus (5), Pollia (19), Polyspatha (3), Porandra (3), Pseudoparis (3), Rhopalephora (4), Sauvallea (1), Siderasis (1), Spatholirion (6), Stanfieldiella (4), Streptolirion (1), Tapheocarpa (1), Thyrsanthemum (3), Tinantia (13), Tradescantia (74), Tricarpelema (8), Tripogandra (22) and Weldenia (1). Uses: Commelina communis is sometimes eaten as a vegetable in Asia. Flowers of this species yield a blue juice, which is used in

COMMELINALES

MONOCOTS

Aneilema aequinoctiale, Royal Botanic Gardens, Kew, UK [114]

Tradescantia hirsuticaulis, Sarah Duke Botanical Garden, Durham, North Carolinas, USA [114]

Commelina diffusa, Picinguaba, Brazil [114]

Cyanotis somaliensis, National Botanic Gardens of Ireland, Glasnevins [114]

Weldenia candida, Royal Botanic Gardens, Kew, UK [114]

Dichorisandra thyrsiflora, Royal Botanic Garden, Sydney, Australia [114]

Japan as a dye for colouring origami paper. It was commonly used as an ink for woodblock prints in 18th and 19th century Japan, but the blue colour is unstable in sunlight. A number of species are grown as ornamentals, as garden and house plants. Even though flowers are ephemeral, lasting only part of the day, they flower over long periods of time, making them valuable ornamentals.

Commelinus senior, who was a successful bookseller and newspaper publisher but did not botanise.

base and linear or sword-like blade, sometimes rounded and then with internal segments. Flowers are formed in axils of spathe-like bracts that are arranged in terminal, simple or compound spikes. The bisexual flowers are zygomorphic, the petals four, free or fused at the base, the outer two larger than the inner two, the upper one often two or three pointed at the tip, a result of fusion of two or three petals. The single stamen is placed above the lower petal and has a broad filament and an anther with two thecae opening by slits. The superior ovary is often somewhat fused with the base of the perianth and filament and has three unequal carpels, the median one often smaller than the lateral two. The fruit is a capsule that splits in threes, or a berry.

Etymology: Commelina is named for Dutch botanists Jan Commelijn (Johannus Commelinus, 1629–1692), founder of the hortus botanicus in Amsterdam, and his nephew Caspar Commelijn (1667–1734), who followed in his uncle’s footsteps. Linnaeus named the genus for the two botanists in the family because of the two well-developed petals of some species of Commelina, leaving its reduced petal to refer to Jan’s brother Casparus

115. PHILYDRACEAE Frogsmouth family

This is a family of perennial herbs with rhizomes and corms. Leaves are all crowded at the base of the plant or some along the flowering stem; they occur in a plane, with a sheathing

Distribution: They occur in Southeast Asia, New Guinea and Australia, with Philydrum Plants of the World

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COMMELINALES

MONOCOTS

Helmholtzia glaberrima, Australian National Botanic Gardens, Canberra [115]

Philydrella pygmaea, Perth, Western Australia

Philydrum lanuginosum, Helsinki Botanical Gardens, Finland [115]

Heteranthera reniformis, Santa Catarina, Brazil [116]

Eichhornia crassipes, Réunion [116]

Pontederia cordata, Chen Shan Botanical Garden, Shanghai, China [116]

lanuginosum extending north to southern Japan and south to Victoria (Australia).

116. PONTEDERIACEAE

herbs. Stems often have rhizomes or stolons. Leaves are alternate and arranged in a plane (distichous), sometimes whorled (in Hydrothrix). They are usually sheathing at base, the stipules large and enveloping the stem (ochrea) or reduced and forming a small ligule. Blades are simple and linear without a petiole or differentiated into petiole and blade. Petioles are sometimes inflated, forming floaters (Eichhornia). Blades are simple, linear to round or heart-shaped, the venation, following the leaf shape and confluent at tip and base. Flowers are solitary, paired or composed of bracteate panicles, spikes or false

[115]

Water-hyacinth family

Phylogeny and evolution: Philydraceae are most closely related to Pontederiaceae plus Haemodoraceae. Crown group Philydraceae are estimated to be c. 33–47 million years old. Genera and species: Philydraceae have three genera with six species: Helmholtzia (3), Philydrella (2) and Philydrum (1). Etymology: Philydrum is derived from Greek φίλος (philos), friend, and υδώρ (hydor), water.

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This is a family of perennial and annual, aquatic, submerged, floating and emergent

COMMELINALES

MONOCOTS

umbels. The bisexual flowers are zygomorphic (sometimes nearly actinomorphic) and have six, sometimes three or four, nearly free petals. The lower median tepal often has a yellow spot. The six, four, three or one stamens are all alike or of two kinds. Filaments are fused with the tepal tube and variously shaped, glabrous or hairy. Anthers have two thecae that are basifixed or appearing dorsifixed, opening by slits or pores. The superior ovary is trilocular but sometimes only one locule is fertile. The single style is usually simple and elongate. The small stigma is entire and round or trilobed. The fruit is a capsule that splits into three or a nutlet with a single seed.

Phylogeny and evolution: Fossil Pontederiaceae are known from Eocene deposits in North America and India. They are sister to Haemodoraceae, the pair then sister to Philydraceae. Diversification in the family is estimated to have occurred c. 40 million years ago. Eichhornia is polyphyletic, with E. meyeri probably sister to the entire family, although this needs further study. Genera and species: This family has six genera and 33 species: Eichhornia (6), Heteranthera (12), Hydrothrix (1), Monochoria (7), Pontederia (6) and Scholleropsis (1).

Distribution: This is a pantropical family, with Pontederia extending into temperate North America. Monochoria and Scholleropsis are Palaeotropical, whereas the others are found in the New World. Eichhornia crassipes has naturalised worldwide in warmer areas, causing havoc in waterways.

Uses: Monochoria leaves are sometimes eaten in Southeast Asia. The water hyacinth, Eichhornia crassipes, has many uses as animal fodder, mulch, compost, paper making and biofuel and for water cleaning. The species is a great pest in warm aquatic systems worldwide. Sometimes pickerelweed (Pontederia) is grown as a pond ornamental.

Anigozanthos manglesii, Perth, Western Australia [117]

Conostylis aculeata subsp. breviflora, Mt Benia, Western Australia [117]

Some tropical submerged species are offered in the aquarium trade but not frequently so. Etymology: Pontederia is named to commemorate Italian botanist Guilio Pontedera (1688–1757), who was a professor in Padua University and director of its botanical garden (the oldest surviving botanical garden). Even though he rejected Linnaeus’s sexual system of classification, Linnaeus named this genus for him.

117. HAEMODORACEAE Kangaroo-paw family

Wachendorfia thyrsiflora, private garden Kingston upon Thames, Surrey, UK [117]

Blancoa canescens, Mt Benia, Western Australia [117]

Haemodorum simplex, Mt Benia, Western Australia [117]

Macropidia fuliginosa, Mt Benia, Western Australia [117]

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COMMELINALES This is a family of perennial herbs with rhizomes, corms and bulbs that are usually reddish or orange. Leaves are basal or located along the flowering stem, alternately placed in one plane (distichous). The base is sheathing (like an Iris), and the blades are sword-like, unifacial, flat and lanceolate or tubular and hollow, sometimes plicately folded. Inflorescences are bracteate and racemose, often comprising a panicle, corymb or head of flowers. The bisexual flowers are actinomorphic or zygomorphic and have two whorls of three simple, basally fused petals, or the two whorls are fused into a single tube with six lobes, the tube splitting on one side when the flower opens (as in Anigozanthos). The three or six stamens are free or fused with the petal tube. Staminodia are sometimes present. Filaments are flattened, and anthers have two thecae opening by longitudinal slits. The superior ovary is tri- (sometimes uni-) locular and

MONOCOTS

bears a terminal style that is round or flattened on one side. The fruit is a capsule that splits in threes or opens by apical pores. Distribution: The greatest diversity in this family occurs in Western Australia. Three genera (nine species) occur in South Africa, and another three genera (five species) are found in tropical America. Lachnanthes caroliniana occurs in eastern North America, from coastal Canada to Cuba.

Blancoa (1), Conostylis (45), Macropidia (1), Phlebocarya (3) and Tribonanthes (6); Haemodoroideae – Barberetta (1), Dilatris (4), Haemodorum (20), Lachnanthes (1), Pyrrorhiza (1), Schiekia (1), Wachendorfia (4) and Xiphidium (c. 3).

Phylogeny and evolution: The stem lineage emerged c. 81 million years ago. Two subfamilies are recognised, which diverged during the early Eocene, c. 47 million years ago.

Uses: Roots of Haemodorum produce a red pigment, which was used to make a drink by the Australian aborigines. It is said to have antitumor and antibacterial properties. Roots of other genera also produce colourful pigments. Many species are valuable ornamental plants, especially species of Anigozanthos, of which many named hybrids are available in the plant trade. They are also sold as cut flowers.

Genera and species: This family comprises 14 genera with 102 species in two subfamilies: Conostylidoideae – Anigozanthos (11),

Etymology: Haemodorum is derived from the Greek αίμα (haima), blood, and δώρων (doron), a gift.

ZINGIBERALES Families 118 to 125 comprise the order Zingiberales. This clade is characterised by giant herbs that have leaves that are rolled up in bud with a distinct petiole and a sheathing base that in many cases forms or clasps a pseudostem. Their blades have a strong midvein and parallel S-curved sideveins. Inflorescence bracts are usually large and persistent, and the flowers are often large, monosymmetric, with variously fused petals and inferior ovaries. The clade evolved roughly 80 million years ago. This age is corroborated by a fossil seed (Spirematospermum) from the Late Cretaceous. These families are all similar in floral and vegetative structure and could be merged. All were traditionally placed together in the ‘family’ Scitaminae, but the separate families were accepted in APG IV because of convention.

118. STRELITZIACEAE Traveller’s-palm family

This is a family of perennial evergreen, often arborescent herbs with axillary suckers or underground runners. The stem is 184

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subterranean and dichotomously branching or erect and woody, with leaves in a terminal, fan-like cluster at the top. Leaves are alternate, arranged in a plane (distichous) and have a sheathing base, a distinct petiole and a pinnately veined blade with parallel, sigmoid lateral veins with crossveins. The basal sheath lacks stipules. The blade is entire, but may be ripped into irregular leaflets by the wind. Inflorescences are terminal or lateral thyrses of one to many spathe-like bracts in which flowers are arranged in axillary cincinnae. Flowers are bisexual, zygomorphic and subtended by ridged bracteoles. The six petals are organised in two unequal

whorls, the outer three free and inner three more or less fused. In Strelitzia, two inner petals are fused to form an arrow-shaped structure that encloses stamens and style in a central groove. Stamens are basically six (in Ravenala), often reduced to five (in other taxa), but no staminode is present. Anthers are basifixed, and the two thecae open by slits. The inferior ovary is trilocular and bears a single filiform style and sunken nectaries. The fruit is a capsule that splits in three, and seeds have brightly coloured, furry arils, orange in Strelitzia, blue in Ravenala and red in Phenakospermum. Flowers are pollinated by birds and lemurs.

ZINGIBERALES

MONOCOTS

Strelitzia reginae, Royal Ravenala madagascariensis, Kusu Botanic Gardens, Kew, UK [118] Island, Singapore [118]

Distribution: Tropical South America, coastal South Africa and Madagascar. Phylogeny and evolution: Previously, the family was treated as a tribe of Musaceae, often placed together with Heliconia. Both are now segregated in separate families because to make Musaceae monophyletic in the traditional sense, Marantaceae and Zingiberaceae would also have to be included. Molecular phylogenetic analyses place Strelitziaceae as sister to the remainder of the order. Strelitziaceae diverged c. 59 million years ago.

Strelitzia nicolai, Santa Barbara, California, USA [118]

the United Kingdom. She was an amateur botanist who lived in Kew Palace for many years and contracted William Aiton and Joseph Banks to develop the gardens at Kew initiated by her mother-in-law, Princess Augusta; these would later become the Royal Botanic Gardens.

119. LOWIACEAE Orchid-lily family

Genera and species: This family includes three genera and seven (or more) species: Phenakospermum (1), Ravenala (1, possibly more) and Strelitzia (5). Uses: Traveller’s pal m, Ravenala madagascariensis, is commonly planted as a garden ornamental in the tropics. Strelitzia nicolai and S. reginae are also commonly available as garden plants. Inflorescences of bird-of-paradise-flower (S. reginae) are popular in the cut-flower trade, but relatively expensive. A yellow-flowered form found at Stellenbosch was named ‘Mandela’s Gold’ in honour of Nelson Mandela. Etymology: Strelitzia was named by Joseph Banks in honour of Charlotte of MecklenburgStrelitz (1744–1818), Queen to George III of

Orchidantha maxillarioides, Royal Botanic Gardens, Kew, UK [119]

long-lived and can bear new branches. The bisexual flowers are zygomorphic, fragrant, usually having a foul odour that attracts beetles. The three sepals are almost equal, narrow and fused into a tube at the base. The three petals are unequal in size and shape, the two lateral ones narrow and small and the middle one enlarged, forming a lip (labellum). The five free stamens have short filaments fused to the petal bases. Anthers have a short connective tip and open by slits. The inferior ovary is composed of three fused carpels that bear nectaries and a elongate style with a trilobed stigma. Fruits are dry capsules that split in three upon ripening, bearing numerous round hairy seeds. Distribution: Restricted to tropical Asia, this family can be found in China, Hainan, Indochina, Malaya, Borneo and Luzon.

A family of glabrous herbs, Lowiaceae are generally terrestrial along streams and near waterfalls in evergreen rainforest or forest clearings. They grow from a horizontal or vertical rhizome that bears scale-like leaves. Leaves are formed at the rhizome apices in distichous tufts. The base is sheathing without stipules, the petiole well-defined and blades lanceolate and entire with pinnate venation composed of a strong central vein and parallel lateral veins that are connected by crossveins. Flowers are solitary on terminal branches (paracladia), held upside down and lasting for only a single day, although inflorescences are

Phylogeny and evolution: This family is most closely allied to Strelitziacae. Genera and species: The single genus Orchidantha has c. 18 species. Etymology: Lowia is named after British colonial administator and naturalist Sir Hugh Lowe (1824–1905), the son of Scottish horticulturalist Hugh Lowe. He made the first documented ascent of Mount Kinabalu in Borneo. Lowia is a later synonym of Orchidantha, which is Greek for ‘orchid flower’. Plants of the World

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ZINGIBERALES

120. HELICONIACEAE Parrot-flower family

This family consists of large, evergreen herbs that grow from a rhizome or produce short erect trunks formed by leaf sheaths. Leaves are sheathing at the base, the sheath without stipules and petioles well defined, often elongate. Blades are often large with a strong midvein and parallel, sigmoid side veins that fuse at the margins and are cross-connected by parallel tertiary veins. Blades are entire, but large ones may be irregularly ripped along

Heliconia psittacorum, cultivated, Réunion [120]

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lateral veins. Inflorescences are terminal and composed of thyrsoid, distichous or helical racemes formed by spathe-like bracts in which cincinnae of flower clusters are formed. The obliquely symmetrical, bisexual flowers are subtended by crested bracts. The six petals and filaments are fused at the base, but five of these petals are fused completely to form a sheath; the remaining petal is free. One of six stamens is staminodial. Filaments are fused to petals, and the anther is basifixed with two thecae opening by slits. The inferior ovary is trilocular with a single filiform style and a capitate stigma. The fruit is a three-seeded berry that is often a peculiar blue or metallic colour. Flowers are pollinated mostly by hummingbirds in the New World and bats in the Pacific. Distribution: Most species are found in tropical America, but a few species are known from the Pacific, Sulawesi and New Guinea to Samoa, Fiji and New Caledonia.

Phylogeny and evolution: Heliconiaceae diverged from Zingiberaceae c. 88 million years ago and diversified c. 32 million years ago. The clade has no fossil record. Traditionally, they have been included in a broader Musaceae, but this would be non-monophyletic if Zingiberaceae and Marantaceae were excluded. Genera and species: This family consists of the single genus Heliconia with 197 species. Uses: In times of famine, flower buds have been eaten in Melanesia. Many species are grown as garden ornamentals or for the cut-flower industry, the colourful bracts lasting for a long time in flower arrangements. Etymology: Latin Heliconia is derived from Ελίκων (Helikon), a mountain in Greece of mythological importance, which in turn is derived from ήλιος (helios), the sun, and κώνος (konos), a cone.

Heliconia bihai, Guadeloupe [120]

Heliconia caribaea, Guadeloupe [120]

Heliconia rostrata, fruit, Tapirai, Brazil [120]

Heliconia rostrata, cultivated, Réunion [120]

ZINGIBERALES

MONOCOTS

Musella lasiocarpa, Kunming Botanical Garden, China [121]

Musa sikkimensis ‘Red Tiger’, male flowers, Royal Horticultural Society Garden, Wisley, UK [121]

Ensete ventricosum, Wundanyi, Taita Hills, Kenya [121]

121. MUSACEAE Banana family

This is a family of giant herbs, some of which are among the largest herbs known. Rhizomes are single or freely suckering, the stems monocarpic (dying after flowering). Alternate, spirally arranged leaves are sheathing at the base, forming a pseudostem, with elongate petioles. The large blades are entire but often split by the wind to the midrib along the parallel sigmoid side veins.

Musa basjoo, Royal Botanic Gardens, Kew, UK [121]

Lateral veins fuse near the margin and are interconnected with smaller cross-veins. The inflorescence is a terminal, indeterminate thyrse that bears a cincinnus of one or two rows in the axils of fleshy spathe-like bracts that recurve when f lowers are opening. The usually functionally unisexual (rarely bisexual) flowers lack bracteoles, and the females form at the base of the inflorescence, whereas the males occur near the apex. The zygomorphic flowers are composed of six petals, of which the outer three and the inner two are fused into a five-lobed or five-toothed sheath, the inner free petal is usually small and opposed. Stamens are usually five, often with a staminodium, which in some cases can be fertile. Filaments are free, and anthers are basifixed with two thecae opening by slits. The inferior ovary is trilocular with a single style that is often wider at the stigma. The fruit is a starchy berry with a leathery skin

Musa acuminata ‘Cavendish’, female flower, Tapirai, Brazil [121]

Musa laterita, Royal Botanic Gardens, Kew, UK [121]

and many large, hard seeds. In some cases, the fruit is ‘self-peeling’. Distribution: Musaceae occur in tropical Africa, Madagascar, South and Southeast Asia, southern China, Malesia, the Philippines, New Guinea, Queensland and Melanesia. Phylogeny and evolution: The crown group is estimated to be c. 40–60 million years old. Eocene seeds of Ensete are known from Oregon, and fossil Spirematospermum seeds from the Tertiary of Europe are also linked to Musaceae. Fossil banana-like leaves from the Early Tertiary of Greenland, Musopsis, could be in this family or another one in Zingiberales. Musella is sister to the rest of the family. Genera and species: This family has three genera with c. 80 species: Ensete (6), Musa (c. 70) and Musella (1).

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ZINGIBERALES Uses: A great variety of bananas are in cultivation. The most popular are the seedless cultivars that are usually triploid and derived from hybridisation between Musa acuminata and M. balbisiana or from just one of these species. The hybrid is often given the name M. ×paradisiaca, which refers to an ancient belief that this was the ‘apple of paradise’, the forbidden fruit of wisdom (which includes the synonym, M. sapientum). Bananas have a history of cultivation and hybridisation for thousands of years in Southeast Asia and China but are now a global commodity. Bananas are, after citrus, the most important fruit crop in the world, typically grown in large monocultures of the cultivar ‘Cavendish’. Fruits of dessert bananas are eaten raw or are juiced, deep-fried, cooked, frozen or dried and chipped. They are even used to make a ketchup-like product (with food colouring to make it red) or to brew beer. Plantains (starch bananas) are grown as a minor crop often in backyard vegetable gardens in the tropics. Plantains are generally boiled or fried before eating. Bananas and plantains are a staple food in most tropical countries. Male buds of Musa inflorescences are cooked as a vegetable in Asia. Leaves are used to wrap food when cooking and are sometimes used as an alternative for a plate or instead of an umbrella in rain. Swollen stems of Ensete ventricosum are used as a source for starch in East Africa. It has been introduced for this reason to the American tropics, where it now naturalises. Manila hemp, Musa textilis, originating in Borneo, is an important fibre crop in the Philippines and Pacific used to make rope and textiles. The Japanese fibre banana, Musa balbisiana var. liukiuense, is a cold hardy selection from the plantain that yields a fine, high-quality fibre highly valued in Japan. Several species such as Musa coccinea, M. ornata, M. splendida, M. velutina and other species of Musa, Ensete and Musella are popular garden ornamentals. Musa basjoo, M. sikkimensis, M. yunnanensis and Musella lasiocarpa have some frost tolerance, making them popular for a tropical touch in temperate gardens. Some of these are now being used to make hardy seedless banana cultivars.

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Etymology: Musa is the Latinised form of ‫زوم‬ (mauz), the Arabic name for banana. Giant banana: Musa ingens from New Guinea can grow over 15 m tall and can have trunks with a two metre circumference. It has leaves more than five metres long and a metre wide (almost as large as the 5.51 m2 of Victoria amazonica, Nymphaeaceae) and produces a giant bunch of inedible bananas with up to 20 hands weighing around 60 kg. It is the largest herb in the world.

122. CANNACEAE Canna-lily family

The fruit is usually a tuberculate, bristly capsule splitting into three. Seeds are hard and round and have been reported to remain viable for 600 years. Distribution: This family occurs in tropical and subtropical areas of the Americas from eastern North America (South Carolina) to southern South America (northern Argentina). They are now cultivated worldwide. Phylogeny and evolution: Morphological and molecular analyses show a close relationship of Cannaceae to Marantaceae. These two are maintained mainly because of their differences in stamen structure. Cannaceae are c. 30 million years old. Canna flaccida from North America is sister to all other species of Canna. Genera and species: The family consists of the single genus Canna with c. 10 species.

This is a family of perennial herbs with tuberous, starchy rhizomes and slime canals in all vegetative tissues. Leaves are alternate, often spiral, but sometimes in one plane (distichous). They are sheathing at the base with an open sheath, lacking stipules, that gradually merges into distinct petioles. The blade is rolled up in bud and is simple and entire with pinnate venation. The midvein is prominent with secondary veins parallel and merging into a vein along the margin. Inf lorescences are terminal thyrses with bracteate cincinnae of flowers held above the leaves. By reduction, this inflorescence may look like a raceme. The bisexual flowers are asymmetrical. The three sepals are free, green or purplish and persistent in fruit. The three petals are unequal in size, one smaller, fused into a tube at the base. The single stamen is petal-like, bearing a single theca along the edge. Other male parts are staminodial, the one to five staminodes petallike, one large one opposite the fertile stamen (labellum) and the others smaller (wings). The inferior ovary is trilocular with a petal-like style and a wet papillate stigmatic surface.

Uses: Edible rhizomes of achira, Canna discolor (syn.: C. edulis), are cultivated throughout the tropics as a staple for humans and livestock. Its starch granules are large and can be seen with the naked eye. Originating in the northern Andes, where it was domesticated around 2500 BC, plants are now grown commercially mainly in India and Australia, where it is known as Queensland arrowroot. A favourite bedding plant in tropical and temperate gardens, there are now thousands of Canna cultivars available, mostly of complex hybrid origin. Canna ×generalis cultivars are hybrids derived initially from C. glauca and C. indica, later also involving C. iridiflora and C. warszewiczii. Hybrids with large lipped flowers were then bred by hybridising C. ×generalis with C. flaccida, forming a cultivar group called C. ×orchidoides. Over time, these two cultivar groups were interbred, and horticultural varieties of Canna are now called only by their cultivar name without a hybrid or species epithet. Etymology: Latin canna (cane) originated from cána, the Irish Celtic word for a cane or reed.

ZINGIBERALES

MONOCOTS

Stromanthe sanguinea, Hong Kong Botanical Garden [123]

Canna glauca ‘Panache’, University of Wisconsin Botanical Garden, Madison, USA [122]

Canna indica var. limbata, Royal Botanic Gardens, Kew, UK [122]

Schumannianthus dichotomus (WA) [123]

Thalia geniculata, Royal Botanic Gardens, Kew, UK [123]

Goeppertia loeseneri, Singapore Botanical Garden [123]

Maranta arundinacea, Singapore Botanical Garden [123]

123. MARANTACEAE

aquatics. They are rosulate and stemless or with elongate branched stems and then lianescent or shrubby. Arial stems are solid and can be bamboo-like with swollen nodes and dry leaf sheaths. Leaves are arranged alternately, usually in one plane (distichous), and are divided into a basal clasping sheath, a distinct petiole that may be absent in some species, a thickened pulvinus and a simple leaf blade. The blade is entire and pinnately veined with a strong midvein and closely set S-shaped secondary veins. The base of the blade is often oblique or sides of the leaf blade are of different size. Blades can be uniformly green, or variously coloured, mottled, striped

or spotted. Flowers are formed in clusters of cymules subtended by a prophyll and arranged in bracteate heads or spikes (thyrses) that are simple or compound. The bisexual flowers are asymmetrical. The three sepals are free, but petals, stamens and staminodes are fused into a tube at least at the base. An outer whorl of staminodes is present and petal-like or rudimentary. An inner whorl is fused at the base into a tube that exceeds the outer tube. It is three-parted: one is fertile and often has a petal-like appendage, one is hood-shaped and the third is firm and fleshy. The inferior ovary is trilocular with two locules often reduced and infertile. The single terminal style is

Prayer-plant family

This is a family of variably sized herbs with rhizomes that are sometimes starchy. They occur in the forest understory and as emergent

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189

ZINGIBERALES fused with the floral tube and often covered by a hood-like staminode in trigger flowers. The stigma is a funnel-shaped depression at the style tip. The fruit is usually a dehiscent capsule, rarely a fleshy berry or nutlet. Distribution: This is a pantropical family of rainforests extending into the warm temperate zones of North and South America.

190

MONOCOTS

horticulturally important species) is to be treated under the genus Goeppertia, making it the largest genus in the family.

and cultivars of these, are popular houseplants or garden plants in the tropics. Thalia dealbata and T. geniculata are popular pond plants.

Genera and species: Marantaceae include 27 genera and c. 555 species: Afrocalathea (1), Calathea (37), Goeppertia (c. 250), Halopegia (3), Haumania (5), Hylaeanthe (5), Hypselodelphys (8), Indianthus (1), Ischnosiphon (36), Koernickanthe (1), Maranta (43), Marantochloa (18), Megaphrynium (5), Monophyllanthe (2), Monotagma (39), Myrosma (1), Phrynium (38), Pleiostachya (3), Sanblasia (1), Saranthe (10), Sarcophrynium (6), Schumannianthus (2), Stachyphrynium (9), Stromanthe (20), Thalia (6), Thaumatococcus (2) and Trachyphrynium (1).

Etymology: Maranta is named for Italian physician and botanist Bartolomeo Maranta (1500–1571), who is most famous for a book on poison antidotes.

124. COSTACEAE

Phylogeny and evolution: Marantaceae are estimated to have diverged from Cannaceae c. 79 million years ago, and the crown group of Marantaceae diversified some 57 million years ago, although sampling of Marantaceae in molecular dating studies has not been adequate for good estimation. They may have originated in Africa, where the diversity of the family is poor, but from there they dispersed to Asia and South America where they diversified. Generic delimitation in Marantaceae is still problematic and even though molecular studies have helped to realign some of these, there remain many issues. Phrynium is paraphyletic. Stachyphrynium and Donax have been readjusted to reflect monophyly, and Calathea was found to be polyphyletic with regard to Ischnosiphon, Monotagma, Pleiostachya and Sanblasia. Instead of merging these three genera with Calathea, it was decided that the majority of Calathea (including the

Uses: Economically, the most important species is arrowroot, Maranta arundinacea, a species from the Caribbean that yields a high-quality starch from the rhizomes. Sweet corn root, Goeppertia allouia, is sometimes grown in the West Indies for its edible tuber. Some species of Maranta and Goeppertia are grown by local peoples for their starchy rhizomes and inflorescences. Larger species of Ischnosiphon, Marantochloa and Schumannianthus are sometimes used for basketry. A great diversity of prayer plants, especially Goeppertia lancifolia, G. makoyana, Maranta bicolor, M. leuconeura

These terrestrial and rarely epiphytic, hairy herbs are perennial and rhizomatous, without oil cells. Stems are round and not or irregularly branched, and often spirally contorted. Leaves are spirally arranged and have a closed tubular sheath with a ligule that extends around the stem above the petiole insertion. Petioles are short and winged, the wing grading into the elliptic to linear, entire blade, which is rolled in bud. Venation is pinnate, the midvein strong, lateral veins

Costus arabicus in fruit, Royal Botanic Gardens, Kew, UK [124]

Hellenia speciosa, Singapore Botanical Garden [124]

Chamaecostus cuspidatus, private collection, Kingston upon Thames, Surrey, UK [124]

Christenhusz, Fay & Chase

Spiral-ginger family

ZINGIBERALES

MONOCOTS

arching toward the apex and partly running parallel to the midvein. The inflorescence is a cone-like spike terminating in a leafy shoot or on separate leafless shoots. Flowers are rarely solitary in the leaf axils (Monocostus). Bracts of inflorescences are imbricate and spirally arranged, often fleshy with nectar glands covering one or two flowers. The bisexual, zygomorphic flowers have sepals fused into a bi- or tri-lobed tube. The petals are fused into a trilobed corolla, the lobes unequal in size. The single stamen is often petal-like and bears two thecae that open by slits. The often more or less trilobed labellum, formed from fused petal-like staminodia, opposes the stamen and is often larger than the corolla. The labellum is fused with the stamen into a small tube. The inferior ovary is tri- (or bi-) locular with two nectaries and a filiform style that is usually enclosed by the thecae of the stamen. The fruit is a capsule that splits into three (or two) or breaks up irregularly. Distribution: This is a pantropical family. Phylogeny and evolution: The clade has been dated to c. 47 million years old. It is most closely related to Zingiberaceae, in which it was previously included as a subfamily. Cheilocostus is a synonym of Hellenia. Genera and species: This is a family of seven genera and 137 species: Chamaecostus (7), Costus (106), Dimerocostus (3), Hellenia (2), Monocostus (1), Paracostus (2) and Tapeinochilos (16). Uses: Unlike the closely related and similar Zingiberaceae, the plants are not aromatic and are therefore not used for spice, although some are used in traditional medicine. Fruit of Dimerocostus is eaten locally in South America. Crepe ginger, Hellenia speciosa, from tropical Asia is used for starch in India, and this species is also the source of diosgenin, used in the production of steroids. Some species of Costus, Hellenia and Tapeinochilos are commonly grown as garden ornamentals in the tropics. Etymology: Costus is Latinised Ancient

Greek meaning “from the East”, referring to the Indian lower Himalaya region from where spices were imported into Greece and Rome.

125. ZINGIBERACEAE Ginger family

This family of perennial herbs has numerous oil cells, making all parts aromatic. Creeping rhizomes are often branched and succulent, or fleshy roots (stilt-roots) can sometimes elevate the rhizome above the ground. Leaves are alternate in a single plane (distichous), either in the same plane as the rhizome or perpendicular to it. Leaf bases have an open sheath clasping the stem; ligules may be present at the tip of the sheath. Blades are usually sessile (or blades are absent at the base of shoots) and simple, elliptic to linear, rolled up in bud with an entire margin. A pulvinus is absent except in Zingiber. Venation is pinnate with a strong midvein and parallel, sinusoid lateral veins. Inflorescences either terminate a leafy shoot, or leaves and inflorescences occur on separate shoots. Inflorescences are lax or contracted racemes, spikes, heads or cone-like, or with the flowers in cincinnae in axils of a bract, forming a thyrse. Bracts are separate and papery or imbricate and fleshy. The bisexual, zygomorphic flowers have a tubular calyx composed of three fused sepals that are trilobed or three-toothed and sometimes split along one side. The three petals are fused into a trilobed corolla, which is tubular basally and has lobes that vary in shape and size, often one much larger than the other two. Only one of six stamens is fertile. In the outer whorl, one staminode is rudimentary, and the other two are petal-like. In the inner whorl, two staminodes are fused into a labellum-like structure. The remaining fertile stamen may not have a filament but

bears an anther with two thecae opening by slits or rarely by pores. The connective is often prolonged into a crest and sometimes spurs at the base. The inferior ovary is initially trilocular, but during development may become unilocular. The style is thin and almost always placed between the thecae, the stigmas are wet and funnel-shaped, often also crested and situated on top of the stamen. Two nectaries occur at the top of the ovary at the base of the style. The fruit is usually a dry or fleshy capsule that splits regularly in three or irregularly in an undefined number, sometimes not dehiscent. Sometimes fruits are united into a fleshy syncarp, which is dispersed as a single unit. Distribution: This is a pantropical family with species extending into the subtropics and temperate zones in Japan, the Himalayas and South Africa. Renealmia is the only American genus and arrived there less than 16 million years ago. Phylogeny and evolution: An age of 65 million years has been suggested for this family, verified by the fossil Zingiberopsis of the Upper Cretaceous or Lower Eocene of North America, but the major diversification took place 26 million years ago. The family is a member of a clade with Cannaceae, Costaceae and Marantaceae, which share petal-like staminodes. Several genera were found to be paraphyletic, and studies on some genera have resulted in a broader concept of, for instance, Globba (including Mantisia) and Curcuma (with inclusion of Laosanthus, Paracautleya, Stahlianthus, Smithatris and some Kaempferia and Hitchenia species). Pyrgophyllum is included in Camptandra. Large genera like Alpinia and Amomum are polyphyletic and are in need of revision. Genera and species: This family has 51 genera and c. 1,600 species in four subfamilies: Siphonochiloideae – Aulotandra (6) and Siphonochilus (11); Tamijioideae – Tamijia (1); Alpinioideae – Aframomum (55), Alpinia (241, polyphyletic), Amomum (188, polyphyletic), Burbridgea (5), Cyphostigma (1), Elettaria (11), Elettariopsis (23), Etlingera (100),

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ZINGIBERALES

MONOCOTS

Alpinia zerumbet, Hong Kong Botanical Garden [125]

Hedychium coronarium, Royal Botanic Gardens, Kew, UK [125]

Roscoea bhutanica, Royal Botanic Gardens, Kew, UK [125]

Globba patens, Mt Datuk, Malaysia [125]

Zingiber zerumbet, New Caledonia [125]

Etlingera elatior, Singapore Botanical Garden [125]

Geocharis (6), Geostachys (25), Hornstedtia (33), Leptosolena (1), Paramomum (1), Plagiostachys (27), Pleuranthodium (23), Renealmia (85), Riedelia (76), Siamanthus (1), Siliquamomum (2) and Vanoverberghia (2); Zingiberoideae – Boesenbergia (68), Borneocola (8), Camptandra (4), Caulokaempferia (30), Cautleya (2), Cornukaempferia (3), Curcuma (109), Distichochlamys (4), Gagnepainia (3), Globba (c. 100), Haniffia (3), Haplochorema (6), Hedychium (93), Hemiorchis (3), Hitchenia (1), Kaempferia (33), Kedhalia (1), Larsenianthus (4), Myxochlamys (2), Nanochilus (1), Newmania (2), Parakaempferia (1), Pommereschea (2), Rhynchanthus (4), Roscoea (21), Scaphochlamys (25), Stadiochilus (1) and Zingiber (144).

a desired commodity in classical times, probably being one of the first exotic spices to be used in Europe, already widely in use by wealthy Romans. The young, mild and fragrant rhizomes are often pickled, candied or cooked fresh in a number dishes. With honey it makes a delicious, anti-inflammatory tea. Sugary stem ginger or candied ginger is frequently used in baked goods or made into a spicy candy. When dried, it is a fragrant, hot spice, used in curries and biscuits, including ginger nuts, gingerbread, ginger snaps and speculaas, and for the production of ginger beer, ginger wine, canton and ginger ale. Ginger is also sliced finely and pickled in Japanese cuisine often served with sushi. Outside Asia, ginger is cultivated on a large scale in Jamaica. Turmeric (Curcuma longa and, to a lesser extent, C. aromatica) has been cultivated in

India for millennia and is used fresh as a spice or dried under heat as a spice or dye. It is native to tropical Asia, where it is commonly grown and used in local cuisine (curries etc.). Fresh leaves can also be used to wrap food before cooking. As a food dye it is known in the EU under E100 and gives a custard yellow colour found in many processed foods and canned beverages. It is often confused with saffron (Crocus sativus, Iridaceae), which has a different hue and flavour. Even though turmeric makes a poor fabric dye because it is light-unstable, it is frequently used for colouring robes of Buddhist monks and Indian saris. Zedoary or white turmeric (C. zedoaria) is also used as a spice, but in Europe where it was already known in the 6th century, it was replaced by ginger. It smells like mango, tastes like ginger, is bitter and is still used in Indian and Thai cuisine.

Uses: Ginger (Zingiber officinale) has been used since ancient times in India and was

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Native to tropical Asia, immature fruits of green cardamom (Elettaria cardamomum) have been used as a spice in local cuisines since ancient times. It was first introduced to Europe in the late 13th century and has ever since been a popular spice, especially in Scandinavia to flavour traditional cakes and pastries and in the Middle East to flavour coffee and tea. Grains of paradise (Aframomum melegueta) is a spice with a pungent, citrusy flavour. Common in West and North African cuisines, it was known in the Mediterranean during ancient times. Today, it is known for its digestive properties and is commercially used to flavour beer, gin and Norwegian aquavit. It is also used in the Caribbean in voodoo rituals. It is commonly used as a spice in East African cuisine and locally to flavour coffee. A number of other species are also used as spice. Nepal cardamom (Amomum subulatum) is used mostly in India and Pakistan and black cardamom (Hornstedtia

costata) in foods in Vietnam and Sichuan. Amomum villosum is cultivated in China for its cardamom-like fruits. Greater galangal or laos (Alpinia galanga) is a spice popular in Thai and Indonesian cuisines, whereas lesser galangal (Alpinia officinarum) flavours Southeast Asian curries, drinks and perfumes, and Russian vinegar and Nastoika liqueur. The Australian ginger (A. caerulea) has edible fruits and can be used as a spice, but is not grown commercially. Korarima or false cardamom (Aframomum corrorima), araththa (Alpinia calcarata), Chinese cardamom (A. globosa), rathkihiriya (A. malaccensis), black ginger (A. nigra), shell ginger (A. zerumbet), fingerroot (Boesenbergia rotunda), kencur (Kaempferia galanga), myoga (Zingiber mioga), cassumunar ginger (Z. montanum), awapuhi (Z. zerumbet) and Renealmia alpina are all minor culinary herbs or spices. The young shoots of some species, such as the porcelain rose (Etlingera elatior) and Tamijia flagellaris, are eaten as a vegetable.

Alpinia nutans is added to food as a preservative in Japan. Many species are cultivated as garden ornamentals in the tropics and warmer temperate regions, especially Alpinia purpurata, A. speciosa, Curcuma alismatifolia, Etlingera elatior and other species of Alpinia, Globba and Hedychium. Several species of Roscoea and Hedychium, Cautleya robusta and Zingiber mioga are frost-tolerant and can be grown in temperate gardens. Hedychium species can become problematic invasives in tropical mountain forest habitats, crowding out the native vegetation and preventing regeneration of natural woodland. Etymology: Zingiber is derived from Sanskrit srngam, a horn, and vera, a body or root, which came into Greek as ζιγγίβερης (ziggiberis), into Latin as zingiberi and gingiber, which became gingimbre in Old French and ginger in modern English, all names for the spice that originated in India.

POALES Families 126 to 139 represent the order Poales. This order evolved c. 100 million years ago (based on molecular calculations), and the crown group is dated to 83 million years, although some fossils are older, such as Protoananas lucenae (Bromeliaceae) from Brazil which is c. 113 million years old and Protograminis laminatus (Poaceae, Pooideae) from Burma, which is estimated to be c. 105 million years old. Therefore, the lineage may be much older than suggested, unless these fossils have not been properly identified. It is unusual to have fossil age estimates for clades that are older than those estimated from molecular clocks.

126. TYPHACEAE Bulrush family

This is a family of glabrous, amphibious herbs with scaly, starchy, creeping rhizomes. They

are usually emergent, growing in muddy soil, or submerged with floating leaves. Leaves are alternate, distichous (in one plane) and sheathing basally. The sheath sometimes forms a short erect stem. Leaf blades are sessile and linear with parallel venation. Inflorescences are racemose, but the unisexual flowers are clustered in dense heads or in cylindrical, cigar-like spikes. Petals are one, three or many and can be small and scale-like or slender and bristle-like. Male flowers usually have three stamens (sometimes fewer or more) with free or fused filaments and basifixed anthers. Female flowers have a superior ovary composed of one

to three fused carpels with a single style and one to three stigmas. The fruit is an indehiscent nutlet, which is plumed in Typha. Distribution: The family is nearly cosmopolitan, apart from the desert regions of Arabia, the Gobi and the Sahara. It is also absent from Borneo and Sulawesi. Phylogeny and evolution: The family is dated to at least 80 million years, and the two genera diverged c. 72 million years ago. Diversification within the genera is more recent. The family has a rich fossil history,

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MONOCOTS

Typha dominguensis in fruit, Palm Springs, California, USA [126]

Typha minima, Royal Botanic Gardens, Kew, UK

Sparganium erectum, near Cambridge, England, UK [126]

Sparganium angustifolium, Isokari, Finland [126]

the earliest possibly dating from the end of the Cretaceous. Sparganium is sometimes placed in its own family, Sparganiaceae, but the two genera share many characters and are merged in APG IV.

127. BROMELIACEAE

and large. Flowers are bisexual or functionally unisexual, usually regular, sometimes slightly oblique, with three fused or free sepals and three fused or free petals. The six stamens form two whorls of three and have free or fused filaments. Anthers have two thecae and open by latrorse slits. The inferior to superior ovary is trilocular and bears a single style with three variously ornate stigmas. Fruits are usually septicidal capsules that split in three or a berry. Seeds are sometimes winged or plumed. Pollination is predominantly by hummingbirds, but other birds, bats and insects (bees, bumble bees, moths and butterflies) are also reported to visit flowers.

[126]

Pineapple family

Genera and species: This family has two genera with c. 50 species: Sparganium (c. 20) and Typha (30). Uses: All parts of Typha are edible, and in the past rhizomes and young male spikes, even pollen, have been consumed. Typha is, like reeds (Phragmites, Poaceae), used for biofiltration of surface water. Both Typha and Sparganium are sometimes grown as pond ornamentals. Etymology: Τυφά (Typha) is the Greek name for cattail, possibly derived from τύφος (tyfos), smoke, in reference to the seeds that may form a cloud when dispersing.

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This is a family of epiphytic and terrestrial, rosette-forming herbs with short or elongate stems that sometimes become woody and tree-like. Roots are usually present, but absent in some epiphytes. Leaves are spirally arranged, simple, entire or prickly toothed, broadened and clasping or sheathing at the base without stipules or ligules. Flowers are formed in terminal, bracteate spikes or condensed heads, the bracts often colourful

Distribution: The family is widespread in the tropical and warm temperate Americas, north to Virginia and south to Patagonia. A single species (Pitcairnia feliciana) occurs in West Africa, a result of recent long-distance dispersal.

POALES

MONOCOTS

Phylogeny and evolution: The stem lineage of Bromeliaceae is dated to 100 million years, but the crown group is much more recent, c. 20 million years old, the majority of the diversification in the family having occurred much more recently. A fossil from the mid-Tertiary of Costa Rica, Karatophyllum bromelioides, is until now the only fossil that can reliably be assigned to this family. Other fossils like the 113 million-year-old fossil of Protoananas has a more dubious relationship to Bromeliaceae. Generic delimitation needs attention, with several found to be non-monophyletic in recent molecular analyses. Eight subfamilies are sometimes accepted. Genera and species: Bromeliaceae include c. 62 genera with c. 3,475 species: Acanthostachys (2), Aechmea (283), Alcantarea (36), Ananas (3), Androlepis (2), Araeococcus (9), Billbergia (65), Brewcaria (6), Brocchinia Guzmania megastachya, Guadeloupe [127]

Bromelia antiacantha, Royal Botanic Gardens, Kew, UK [127]

(20), Bromelia (63), Canistropsis (11), Canistrum (13), Catopsis (19), Cipuropsis (10), Connellia (6), Cottendorfia (1), Cryptanthus (78), Deinacanthon (1), Deuterocohnia (20), Disteganthus (2), Dyckia (163), Edmundoa (3), Eduandrea (1), Encholirium (28), Fascicularia (1), Fernseea (2), Fosterella (31), Glomeropitcairnia (2), Goudaea (2), Gregbrownia (4), Greigia (36), Guzmania (218), Hechtia (64), Hohenbergia (68), Hohenbergiopsis (1), Lapanthus (3), Lindmania (39), Lymania (9), Navia (93), Neoglaziovia (3), Neoregelia (125), Nidularium (47), Ochagavia (4), Orthophytum (67), Pitcairnia (c. 410), Portea (8), Pseudaechmea (1), Puya (230), Quesnelia (23), Racinaea (76), Ronnbergia (13), Sequencia (1), Sincoraea (1), Steyerbromelia (6), Stigmatodon (18), Tillandsia (c. 700), Ursulaea (2), Vriesea (c. 225), Werauhia (96), Wittrockia (7), Waltillia (1), and Zizkaea (1).

Uses: Pineapple, Ananas comosus, is the most important economic plant of this family. The fruit is composed of berries that coalesce with the fleshy bracts and rachis of the inflorescence, forming a fleshy, juicy compound fruit. Pineapples can be eaten fresh or cooked, juiced, dried or jammed, and are used in many cuisines. Pineapples are rich in bromelain, an enzyme that breaks down proteins and can be used as a meat tenderiser and in the pharmaceutical industry. Some species of Bromelia also have edible fruits but are only consumed locally. Leaves of pineapple plants are sometimes used to make fibre used in wallpaper etc. Several species produce useful, strong fibres, especially caroá, Neoglaziovia variegata, and caraguá, Ananas lucidus, which are commonly used in South America. Puya chilensis fibres are used to make durable fishing nets.

Ananas comosus, plantation in Paraná, Brazil [127]

Tillandsia usneoides clothing trees in North Carolina, USA [127]

Pitcairnia macrobotrys, Royal Botanic Gardens, Kew, UK [127]

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POALES Spanish moss, Tillandsia usneoides, is a rootless epiphyte that was formerly important in the southern USA as packing material and for stuffing of pillows and cushions. Spanish moss and other epiphytic Tillandsia species are good indicators of air quality. Many bromeliads are cultivated as ornamentals. Giants, dwarfs and carnivores: Queen of the Andes, Puya raimondii, is the largest of all bromeliads, making a vegetative growth to c. 4 metres and up to 10 metres tall when flowering, with an inflorescence bearing over 3,000 flowers. The related Puya chilensis is infamous for being hazardous to sheep and birds, which can get impaled or otherwise caught by its leaves. It has therefore been considered to be inadvertently carnivorous because the decaying corpses can provide nutrients to the plants. Many species of bromeliads collect water in the middle of their rosette of tightly overlapping leaves. These cups,

Guacamaya superba, habit, Colombia (MF) [128]

Schoenocephalium teretifolium, Colombia (MF) [128]

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called phytotelmata, often house entire ecosystems, including treefrogs, land crabs, insects, earthworms, protists and even aquatic angiosperms (e.g. Utricularia, Lentibulariaceae) and algae. A highly endemic fauna is found in these tanks. A few species are believed to have perfected this cup into a trap for insects to gain additional nutrients. Most famous is Brocchinia reducta, which has UV-reflecting scales on the insides of the cup that lure insects that fall into the liquid, where they drown and decompose. The plant does not produce enzymes as do some carnivorous plants in other families, but it is considered a carnivorous plant in the true sense because it absorbs the nutrients through adventitious roots. Similarly, Catopsis berteroniana has also been suspected of carnivory. Tillandsia includes some of the smallest bromeliad species, and being air plants lacking roots, species like T. recurvata can cover electricity and telephone wires in tropical America.

Etymology: Bromelia commemorates Swedish physician and botanist Olaus Bromelius (Olof af Bromell, 1639–1705), who was famed for owning a large botanical library.

128. RAPATEACEAE Tow-tow family

Terrestrial and epiphytic, sometimes emergent aquatic, perennial herbs comprise this family. They have creeping rhizomes with leaves clustered at the tip of a short stem emerging from the rhizome. Leaves are mostly in one

Rapatea paludosa, Colombia (MF) [128]

Duckea cyperaceoidea, Colombia (MF) [128]

Monotrema bracteatum, Colombia (MF) [128]

POALES

MONOCOTS

Xyris sp., habit, Bertioga, Brazil [129]

Xyris sp., Bertioga, Brazil [129] Xyris involucrata, Colombia (MF) [129]

plane (distichous), and fan-shaped, but are sometimes somewhat spiralling or twisting, the bases asymmetrical and flattened, with ligules or petioles rarely present at the tip, sometimes with the blades perpendicular to bases. Leaf blades are grass-like, linear or lanceolate, sometimes elliptic, with parallel venation, the veins meeting at the tip and base of the leaf. Inflorescences are terminal or axillary from a leaf sheath and solitary or many in a head. Flowers are formed in bracteate spikelets, which in turn are aggregated in heads that are surrounded by two, rounded or flattened bracts. The bisexual flowers are regular or slightly zygomorphic. They have three sepals and three petals that are fused at the base into a small tube. The six stamens are in two whorls, and the filaments are basally fused to each other or to the corolla tube. The anthers are basifixed, often with apical appendages and two thecae that open by one, two or four apical pores. The superior ovary is trilocular (or unilocular by abortion of the other two) and bears a single erect style with a capitate stigma. The fruit is a septicidal capsule.

Monot remoideae, Rapateoideae and Saxofriedericioideae. Rapateaceae occupy an isolated position in Poales, as sister to what some authors have termed core Poales (the combined cyperid and graminid clades). Genera and species: Rapateaceae have 17 genera with 94 species: Amphiphyllum (1), Cephalostemon (5), Duckea (4), Epidryos (3), Guacamaya (1), Kunhardtia (2), Marahuacaea (1), Maschalocephalus (1), Monotrema (4), Phelpsiella (1), Potarophytum (1), Rapatea (22), Saxofridericia (8), Schoenocephalium (4), Spathanthus (2), Stegolepis (33) and Windsorina (1). Etymology: Rapatea is derived from an Amerindian name for the plant, probably from the Wayampi language in French Guiana.

129. XYRIDACEAE Yellow-eyed-grass family

Distribution: This family occurs in tropical South America and coastal West Africa. The single African representative, Maschalocephalus dinklagei, arrived there by recent long-distance dispersal. Phylogeny and evolution: The origin of Rapateaceae is dated to c. 79 million years ago. It has no known fossil record. The family is sometimes split into three subfamilies:

Abolboda pulchella, Colombia (MF) [129]

unifacial, laterally flattened, rarely rounded or angular. Lateral or terminal inflorescences have a long peduncle, emerging from a specialised sheath or from the inner leaves, with or without bracts along the stem. Bracts are present below the flowers. Each peduncle bears one-, rarely two bracteate spikes or heads, or sometimes a panicle composed of spikes. The actinomorphic, bisexual flowers are one to many per inflorescence, each singly in the axils of a bract. Usually there is only one or a few open in the inflorescence at any time. The three sepals are all equal in size and shape, or one is reduced to a scale or absent. In Xyris the sepals are thin and wrapped around the corolla. Three petals are usually equal, sometimes unequal, free or fused into a two-lipped corolla, the bases clawed or fused into a narrow tube. Three (rarely six) stamens oppose the petals. Anthers are bilocular, opening by slits. Staminodia are usually three, sometimes one, filamentous or branched, often densely hairy. The superior ovary is unilocular or partly trilocular with a terminal three-branched or simple style with a variably shaped stigma. The fruit is a capsule that usually splits into three. Distribution: This is a pantropical family, extending to temperate eastern North America (Great Lakes and Nova Scotia) and temperate Australia and Tasmania.

This is a family of perennial herbs with leaves emerging from a creeping or erect rhizome. Leaves are spirally arranged or in a fan, the bases broad and open, sheathing, the sheaths often flat and keeled, and the blades usually

Phylogeny and evolution: Xyridaceae are most closely related to Eriocaulaceae and Mayacaceae, with which they share several characters and habitat preferences. In this part of the graminid/cyperid clade, relationships Plants of the World

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have not always been well resolved or well supported. The stem group of Xyridaceae is c. 87 million years old. The family is sometimes divided into two subfamilies, Abolbodoideae and Xyridoideae. Genera and species: Xyridaceae include five genera and c. 395 species: Abolboda (21), Achlyphila (1), Aratitiyopea (1), Orectanthe (2) and Xyris (c. 370). Etymology: Xyris is derived from the Greek ξυράφι (xyrafi), a razor, in reference to the sharply edged leaves of some species.

130. ERIOCAULACEAE Pipewort family

This is a family of perennial and sometimes annual, terrestrial and aquatic herbs. Plants are usually rosulate and tufted but can have all leaves along an erect stem in some genera. Stems are usually hairy. Leaves are usually spirally arranged, sometimes two-ranked, with or without a clasping base, linear to

Syngonanthus caulescens, Colombia (MF) [130]

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lanceolate with parallel venation. Flowers are borne in dense head-like spikes on thin peduncles that may be solitary or compound in various several-times-umbellate structures composed of several to hundreds of these heads. Each peduncle has a closed sheath at the base. Each head is subtended by fused bracts (involucre) and contains ten or more usually unisexual flowers, each subtended by smaller free bracts that can be petal-like. Flowers are usually regular but can be zygomorphic. Sepals are two or three and various in colour, the petals are two or three, usually colourless or white. Stamens can be in one whorl, then only two or three, or in two whorls, then four or six or reduced to a single stamen. Anthers are dorsifixed or basifixed and have two cells. The superior ovary is bi- or trilocular with the same number of styles. The fruit is a loculicidal capsule spliting on the side. Distribution: This is a pantropical family, extending into the temperate zones in southern California, north to the Great Lakes and Newfoundland in eastern North America, south to Argentina; also in Scotland, Ireland, Sub-Saharan Africa, Madagascar, Asia north to the Himalayas, Manchuria, eastern Siberia and Japan and south to eastern Australia (Victoria). The family is especially diverse in the Guiana Shield and Atlantic Brazil. Phylogeny and evolution: Because of their unique inflorescence and pollen type, Eriocaulaceae have always been considered a

Tonina fluviatilis, Bertioga, Brazil [130]

natural entity. The clade (stem node) is at least 58 million years old. Generic delimitation in Eriocaulaceae is debated and still unclear, and genera such as Syngonanthus may have to be divided or others may have to be merged with it. They are closely related to Xyridaceae. Genera and species: This family has ten genera and c. 1,207 species: Actinocephalus (33), Comanthera (41), Eriocaulon (c. 480), Lachnocaulon (7), Leiothrix (64), Mesanthemum (15), Paepalanthus (420), Rondonanthus (6), Syngonanthus (140) and Tonina (1). Uses: Syngonanthus chrysanthus is occasionally grown as a houseplant. Inflorescences of several species are collected in Brazil for dried flower arrangements, although this harvesting is not believed to be sustainable. Golden grass (Syngonanthus nitens) is used for handicrafts. Tonina fluviatilis is occasionally cultivated as an oxygenating plant for tropical ponds or aquaria. Carnivory: Paepalanthus bromelioides shares the habitat of Brocchinia reducta (Bromeliaceae), its leaves also forming a tank that may similarly function to catch insects, although this is speculative. No study has been carried out on possible trapping, digesting or absorbing mechanisms in this species. Etymology: Eriocaulon is composed from the Greek έριο (erion), wool, and καυλος (caulos), stem or penis.

Eriocaulon decangulare by W. J. Hooker from Curtis’s Botanical Magazine vol. 59: 3126, 1832 [130]

Paepalanthus bromelioides, Caraguatatuba, Brazil [130]

POALES

MONOCOTS

Mayaca fluviatilis, Colombia (MF) [131]

Mayaca fluviatilis, Singapore (KH) [131]

Thurnia sphaerocephala, Guyana (PM) [132]

Prionium serratum, Karatara River, Western Cape, South Africa (CD) [132]

131. MAYACACEAE

is unilocular with a single style and short stigma. The fruit is a loculicidal capsule that splits in three.

132. THURNIACEAE

Bog-moss family

Palmiet family

Distribution: Mayacaceae occur in tropical America from southern North America to Uruguay and southern tropical Africa.

This is a small family of rooted, submerged, aquatic herbs that lack vessels in stems and leaves. Narrow, linear or filiform leaves are spirally arranged and sessile, and often have two teeth at the tip. Flowers are solitary in leaf axils, although seemingly terminating a stem and growing from a broad prophyll or bract. Flowers occur on pedicels that lift the flower above the water surface. Flowers are bisexual and have a differentiated calyx and corolla. The three sepals are green, the three petals white and narrowed at the base. The three stamens alternate with the petals and have slender filaments and basifixed anthers that open by apical pores. The superior ovary

Phylogeny and evolution: Previously, the family was thought to be related to Commelinaceae, but it is now known to be sister to a clade of Thurniaceae, Juncaceae and Cyperaceae or to Eriocaulaceae plus Xyridaceae. The stem lineage of Mayacaceae diverged from their relatives c. 100 million years ago. Genera and species: The family consists of the single genus Mayaca with six species. Uses: Mayaca fluviatilis is sometimes used as an aquarium plant. Etymology: Mayaca is an Amerindian name for the plant, probably from the Wayampi language as its name was first recorded in French Guiana.

This family of perennial herbs has erect woody trunks and subterranean rhizomes. Leaves are spirally arranged or three-ranked and clustered near the apex of the stems. They are linear and sheathing or clasping the stem at the base. Venation is parallel, the margins serrate. The inflorescence is a terminal bracteate panicle or a dense, globose head subtended by leafy bracts. Flowers are bisexual with six equal and dry petals in two whorls. The six stamens are free, the filaments slightly fused with the petals, and the basifixed anthers open by slits. The superior ovary is tricarpellate, the tip of the ovary elongated into a style with three free branches and dry Plants of the World

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POALES stigmas. The fruit is a loculicidal capsule that splits in three. Distribution: Thurniaceae occur in Guiana Shield in South America (Thurnia) and South Africa (Prionium). Phylogeny and evolution: The family is closely related to Juncaceae and Cyperaceae and was previously included in the former by many authors. They share tetrad pollen with Juncaceae, but Juncaceae lack the silica bodies common in Thurniaceae and Cyperaceae. The family is c. 98 million years old, but the crown node diverged c. 33 million years ago. Genera and species: This family has two genera with four species: Prionium (1) and Thurnia (3). Etymology: Thurnia is named in honour of the discoverer of the genus, British botanist, explorer and photographer Sir Everard Ferdinand im Thurn (1852–1932), who was curator of the British Guyana Museum, one of the first naturalists to climb Mount Roraima and later governor of Fiji.

133. JUNCACEAE Rush family

MONOCOTS

is formed of three fused carpels, topped by a three-branched filiform style. The fruit is a loculicidal capsule that splits in three. Distribution: The family occurs worldwide but is remarkably absent from the Amazon region and large parts of subtropical Africa, Madagascar and northern Australia. Phylogeny and evolution: Juncaceae are not well represented in the fossil record. Luzula is known from the Upper Oligocene in Germany, and there are Miocene fossils and fossil pollen known from Russia and North America. Molecular dating estimates this family to be c. 74 million years old. Genera and species: The family has seven genera and 460 species: Distichia (3), Juncus (325), Luzula (120), Marsippospermum (4), Oxychloë (5), Patosia (1) and Rostkovia (2). Uses: Juncaceae are often important pasture plants, but they have little other use. Juncus effusus and J. rigidus are sometimes woven into mats and into children’s toys (in a similar manner to corn dollies made from cereal straw). The pith of J. effusus can be used as a lamp-oil wick. Distichia is used for fuel in the Andes. Some species of Luzula are occasionally offered as garden ornamentals. Etymology: Juncus is the classical Latin name for rush.

134. CYPERACEAE Sedge family

Flowering stems of these plants are erect, the inflorescences terminal or appearing lateral, often composed of compound open cymose panicles or contracted into heads. Flowers are sometimes solitary. The bisexual or unisexual flowers usually have six (rarely four) free petals that are arranged in two whorls. The usually six stamens are also in two whorls, although the inner whorl may be absent. Filaments are filiform or flattened, and the anthers have two locules opening by slits. The superior ovary

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rhizomes that sometimes form stolons, bulbs or an erect trunk. Stems with nodes emerge from a leaf sheath, which is sometimes thickened at the base, often triangular in cross-section, or round to slightly flattened and sometimes winged. Leaves form a basal rosette, or there are few to many along the stem, rarely all cauline, usually spirally arranged in three (sometimes two) ranks. Lowermost, often underground, leaves are frequently reduced to sheaths. Leaf sheaths are usually closed, with or without a ligule on top. Blades are usually linear, sometimes a little broader and oblong, or inrolled and round in cross-section with parallel venation. The bisexual or functionally unisexual flowers occur in spikelets, which in turn form capitula, corymbs, panicles, spikes or umbels or are reduced to a single solitary spikelet. Spikelets are composed of bracts arranged along a slender axis (called a rachilla), with one to many bracts (glumes) subtending florets. Spikelets usually have a prophyll, which in some taxa (e.g. Carex) becomes bottle-shaped and encloses the rachilla and single flower. Flowers lack petals, but often have three to six (or many) scales that are bristle-like or rarely flat and laminar. There are usually three stamens, but sometimes one, two, four or six (or more), the filaments often elongating, usually free, with a basifixed anther that has an arrow-shaped base and connective often forming a crest. The superior ovary is usually unilocular, formed by three fused carpels and is therefore more or less triangular, or when of two carpels, somewhat flattened. The style is usually long and has three papillate stigmatic branches. The fruit is usually a nutlet, rarely a small drupe. Distribution: This is one of the most widespread families. They are cosmopolitan but absent from Antarctica and the permanent ice sheet of Greenland.

These annual and perennial herbs, shrubs and lianas grow terrestrially or sometimes epiphytically, often on wet ground or in aquatic habitats. Perennial species usually have

Phylogeny and evolution: Cyperaceae are sister to Juncaceae. The fossil record of Cyperaceae pollen and fruit starts in the Palaeocene. It is well represented in Cenozoic deposits of North America and Europe. The crown node of Cyperaceae is dated to be c. 76 million years old, and Cyperoideae diversified

POALES

MONOCOTS

Luzula campestris, near Turku, Finland [133]

Luzula alopecurus, Royal Botanic Gardens, Kew, UK [133]

Mesomelaena tetragona, Western Australia [134]

Caustis dioica, Mt Benia, Western Australia [134]

Luzula luzuloides, Royal Botanic Gardens, Kew, UK [133]

Cyperus papyrus, Jardin des Plantes, Paris [134]

Rhynchospora alba, Lake District, England, UK [134]

Juncus effusus, Lake District, England, UK [133]

Eriophorum angustifolium, Lake District, England, UK [134]

Schoenoplectus californicus var. paschalis, Easter Island [134]

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POALES c. 77 million years ago. Mapanioideae diversified later, c. 33 million years ago. Mapanioid fossils are known from the Eocene of Europe. Genera and species: Cyperaceae include 100 genera with c. 5,500 species and are divided in two subfamilies: Mapanioideae – Capitularina (1), Chorizandra (5), Chrysitrix (4), Diplasia (1), Exocarya (1), Hypolytrum (60), Lepironia (1), Mapania (85), Paramapania (7), Principina (1) and Scirpodendron (2); Cyperoideae – Actinoschoenus (3), Actinoscirpus (1), Afroscirpoides (1), Afrotrilepis (2), Amphiscirpus (1), Androtrichum (2), Arthrostylis (1), Ascolepis (22), Becquerelia (7), Bisboeckelera (3), Blysmus (4), Bolboschoenus (15), Bulbostylis (215), Calyptrocarya (8), Capeobolus (1), Carex (1,829), Carpha (15), Caustis (5), Cephalocarpus (4), Cladium (3), Coleochloa (8), Costularia (24), Crosslandia (1), Cyathochaeta (5), Cyathocoma (3), Cymophyllus (1), Cyperus (704), Cypringlea (3), Diplacrum (9), Dracoscirpoides (3), Dulichium (1), Eleocharis (284), Epischoenus (8), Eriophorum (16), Erioscirpus (2), Evandra (2), Everardia (11), Ficinia (77), Fimbristylis (305), Fuirena (59), Gahnia (41), Gymnoschoenus (2), Hellmuthia (1), Isolepis (76), Karinia (1), Khaosokia (1), Kobresia (58), Koyamaea (1), Kyllinga (80), Lagenocarpus (30), Lepidosperma (74), Lipocarpha (35), Machaerina (50), Mesomelaena (5), Microdracoides (1), Morelotia (2), Neesenbeckia (1), Nelmesia (1), Nemum (8), Neoscirpus (1), Oreobolopsis (3), Oreobolus (17), Phylloscirpus (3), Pleurostachys (33), Pseudoschoenus (1), Ptilothrix (1), Pycreus (118), Reedia (1), Rhodoscirpus (1) Rhynchocladium (1), Rhynchospora (354), Schoenoplectiella (51), Schoenoplectus (29), Schoenoxiphium (21), Schoenus (108), Scirpoides (3), Scirpus (50), Scleria (252), Sumatroscirpus (1), Tetraria (54), Trachystylis (1), Trianoptiles (3), Trichophorum (12), Trichoschoenus (1), Tricostularia (5), Trilepis (5), Uncinia (69), Volkiella (1) and Zameioscirpus (3). Uses: Pith of papyrus (Cyperus papyrus) is still used to make a paper-like material.

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Papyrus is a native of the Upper Nile in South Sudan but was already in ancient times brought to the Lower Nile in Egypt, where it soon naturalised and covered the shores. It is probably the earliest account of an invasive species caused by human introduction. The oldest known papyrus documents date from c. 2555 BC, but the method of using papyrus probably developed some 500 years earlier. Stems are first peeled and the inner pith cut lengthwise into thin slices, which are then placed on a flat surface with the edges overlapping. It is then covered with a second layer at right angles to the first. While still moist, the two sticky layers are pounded together, and then pressure is applied under which the sheet dries. When dry the sheet is polished with a round, smooth stone or wooden tool. Papyrus is suitable for use as paper in dry climates and was commonly used around the Mediterranean and the Middle East, but in damp climates it is not suitable because the cellulose soon becomes mouldy. In the 1st century, papyrus became more expensive and was soon replaced by the cheaper and more durable parchment and later by wood-based paper. By the 18th century, C. papyrus had become extinct in Egypt. Machine-manufactured papyrus was developed in the 1960s, and currently there are minor papyrus industries in Egypt and Sicily to satisfy the tourist market. In Central Africa papyrus is also used to make handicrafts, mats, furniture etc. It has also been under consideration for production of biofuel in some African countries. When harvested sustainably, this has great potential. It also has potential to be used for biofiltration of eutrophic or polluted water. The earth almond, or yellow nutsedge (Cyperus esculentus), has been cultivated for its edible tubers since 3000 BC in Egypt and spread from there across Europe, Africa and Asia. The tubers, called tigernuts, used to be sold as a treat in many European countries but have gone out of fashion. It is well known for the Spanish drink, horchata de chufa. The species is underused, especially because it is considered one of the worst invasive weeds. Tubers of the purple nutsedge (C. rotundus) can also be eaten but have a bitter taste.

Totora reeds (Schoenoplectus californicus) are locally woven into boats and rafts, especially in Lake Titicaca and on Easter Island. Some species of Schoenoplectus are used for water and sewage treatment. Several other species of Cyperaceae are locally used for weaving mats and baskets. A number of species are sometimes grown as ornamentals, mainly members of the genera Carex, Caustis, Cyperus, Eriophorum, Schoenoplectus and Uncinia. The umbrellaplant (Cyperus involucratus) is a common houseplant. Etymology: Cyperus is the Latinised form of the classical Greek name for nutsedge, κύπερος (kyperos).

135. RESTIONACEAE Fynbos family

This family consists of evergreen, perennial, r ush-like, usually unisexual plants, sometimes diminutive and ephemeral. Their photosynthetic stems are arranged in clumps arising from creeping rhizomes. The round, flattened or quadrangular stems are simple, forking or branching in whorls and can be confused with horsetails (Equisetaceae) or bamboos (Poaceae). Leaves are usually reduced to yellow, tan or brown sheaths surrounding nodes, split to the base on one side. Sheath tips often have thin lobes or a membranaceous margin, sometimes extending into an awn or reduced leaf blade. On juvenile stems leaf blades are often more developed, sometimes also persistent in adult plants, or in some taxa leaves are normally developed, in basal rosettes with laterally flattened (Anarthria) or terete blades with open sheaths (Centrolepidoideae). The flowers are arranged in bracteate spikes or branched

POALES

MONOCOTS

Anarthria scabra, male, near Albany, Western Australia [135]

Anarthria scabra, female, near Albany, Western Australia [135]

Elegia capensis, female, National Botanic Gardens of Ireland, Glasnevin [135]

Rhodocoma capensis, National Botanic Gardens of Ireland, Glasnevin [135]

Lyginia imberbis, female, near Perth, Western Australia [135]

Alexgeorgea subterranea, Mt Benia, Western Australia [135]

racemes, often sexually differentiated. Flower spathes can be large, covering the f lowers or small and unremarkable, sometimes condensed into two-ranked or head-like spikelets. Flowers can be solitary or arranged in spikelets and surrounded by one or two bractlets, often with the lower bractlet flowerless (as in grasses). Flowers are usually unisexual with a six-parted perianth, usually in two whorls of three, sometimes fewer or perianth absent. Male flowers have six or three stamens with free (sometimes fused) filaments and dorsifixed dangling anthers and usually a minute pistillode, in Centrolepidoideae reduced to a single stamen. Female f lowers have staminodes or lack stamens altogether. The ovary is superior, uni- to trilocular and free, with one to three, bushy styles that are sometimes fused at the base and have finely branched stigmas, or are filiform and covered with stigmatic papillae. In Centrolepidoideae the female f lowers

are single carpels with a unilocular ovary, sometimes united with adjacent carpels into pseudanthia. Fruits are capsules, nutlets or follicles opening by a slit. Distribution: Well known from southern Africa, the family also occurs in Madagascar, Southeast Asia, Malesia, Australia, New Zealand, Melanesia, southern South America and the Falkland Islands. It is particularly diverse in South Africa and Australia. Phylogeny and evolution: Distinctive fossil pollen shows that the family dates back at least to the Late Cretaceous and may have a Gondwanan origin, which corresponds with its modern-day distribution, although because the crown group of Restionaceae is dated to 74 million years old, its current distribution is more likely to be a result of long-distance dispersal. Fossil pollen shows that it may have been widespread in the Northern

Desmocladus fasciculatus, male, near Perth, Western Australia [135]

Centrolepis aristata, near Perth, Western Australia [135]

Hemisphere during the Tertiary, although the identity of the pollen is uncertain, and it may belong to any of the related families. Former Anarthriaceae (including Hopkinsiaceae and Lyginiaceae) form a sister lineage to other Restionaceae and can be maintained as a family, but these are so similar that it seems obvious to unite the two. The clade evolved c. 55 million years ago. Molecular studies place Centrolepidaceae on a long branch as sister to Australian Restionaceae (Leptocarpoideae and Sporadanthoideae), together forming a clade sister to the African Restionoideae. Therefore they are included in Restionaceae in their own subfamily. Centrolepidoideae split from other Australian Restionaceae c. 45–97 million years ago. Hydatellaceae, which are superficially similar, were previously treated as part of this family, but are now known to belong to Nymphaeales, a case of convergent evolution.

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POALES Genera and species: This is a family with five subfamilies including c. 55 genera and c. 572 species: Anarthrioideae – Anarthria (6), Hopkinsia (2) and Lyginia (3); Restionoideae – Anthochortus (15), Askidiosperma (12), Calopis (23), Cannomois (12), Ceratocaryum (6), Coleocarya (1), Dielsia (1), Elegia (51), Hydrophilus (1), Hypodiscus (15), Ischyrolepis (48), Mastersiella (13), Nevillea (3), Platycaulos (c. 8), Restio (c. 100), Rhodocoma (7), Soroveta (1), Staberoha (c. 9), Thamnochortus (34) and Willdenowia (12); Centrolepidoideae – Aphelia (6), Centrolepis (26) and Gaimardia (4); Leptocarpoideae – Alexgeorgea (3), Apodasmia (4), Baloskion (8), Catacolea (1), Chaetanthus (3), Chordifex (20), Cytogonidium (1), Dapsilanthus (4), Desmocladus (15), Empodisma (3), Eurychorda (1), Harperia (4), Hypolaena (8), Kulinia (1), Lepidobolus (c. 10), Leptocarpus (3), Loxocarya (5), Meeboldina (11), Melanostachya (1), Onychosepalum (3), Platychorda (2), Stenotalis (1), Taraxis (1), Tremulina (2), Tyrbastes (1) and Winifredia (1); Sporadanthoideae – Calorophus (2), Lepyrodia (22) and Sporadanthus (8), Uses: Few species are used commercially. Thamnochortus insignis is locally used in South Africa for thatching. Fynbos vegetation has contributed to the formation of peat in South Africa, which is being exploited unsustainably. Some species are used as garden ornamentals, with Elegia capensis being the most commonly used species due to its frost tolerance, although other Cape Restionoideae are gaining favour.

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136. FLAGELLARIACEAE Whip-vine family

Etymology: Flagellaria is named for the leaves that have a flagelliform or whip-shaped tip (a tendril).

137. JOINVILLEACEAE Ohe family

This family includes herbs with perennial shoots and clustered rhizomes. Stems are solid and glabrous. Leaves are alternate, clasping the nodes, in a plane (distichous). Leaf bases are sheathing with the sheath closed around the stem. Blades are lanceolate, with a constricted base and a long-acuminate tip that is curled up into a tendril (flagellum), with which it climbs. Inflorescences are spikes composed of a terminal panicle-like racemes. Flowers are bisexual with six persistent tepals in two whorls, the bases of which are slightly fused and thickened. Each tepal has a single vein. The six stamens are in two whorls with short filaments and the linear basifixed anthers open by slits. The superior ovary is composed of three fused carpels, trilocular and topped by three short spreading styles. Fruits are red or black, one-seeded berries. Distribution: This family is found in tropical and southern Africa, throughout the Indian Ocean islands to India, Malesia and the western Pacific.

Underground: Alexgeorgea subterranea was discovered by Sherwin Carlquist in 1974 near Jurien Bay in Western Australia. At first he only found male plants of this new species, but he needed female plants to describe it. He then noted purple thread-like structures emerging from the sand, which, after some digging, turned out to be the styles of the otherwise underground female flowers.

Phylogeny and evolution: Previously, Hanguana and Joinvillea were included in this family, but the relationship with Hanguana (Commelinales) is remote, and Joinvillea, even though in Poales, is also excluded on morphological and phylogenetic grounds. Flagellaria is sister to Joinvilleaceae plus Poaceae/Ecdeiocoleaceae. Flagellaria-type pollen is known from the Upper Miocene with certainty, and Eurasian material from the Tertiary probably also belongs here. The stem node is c. 90 million years old.

Etymology: Restio means ‘maker of rope’ and is derived from Latin restis, a rope or cord.

Genera and species: The sole genus, Flagellaria, has four species.

Christenhusz, Fay & Chase

Uses: Some species are used for basketry. Flagellaria indica has some medicinal properties.

This family of large herbs grows from a short rhizome and has unbranched, hollow, round or slightly flattenened shoots with solid nodes. Leaves surround the stem at nodes and are sheathing basally, the sheath opens with a ligule-like structure. Blades are linearlanceolate with parallel venation in which veins merge at the margin and tip, and the lamina is plicately folded. Blades are usually hairy. Inflorescences terminate stems and are many-flowered, pendent panicles composed of spikes or racemes. Flowers are bisexual, regular, and trimerous. The six free or nearly free tepals are bract-like, dry and persistent in fruit. Each tepal has three veins. Stamens are free or somewhat fused with the tepal bases, the anthers basifixed, arrow-shaped and opening by slits. The superior ovary is trilocular and has three free styles with feathery stigmas. Fruits are drupes with one to three hard seeds. Distribution: This family occurs on islands in Malesia into the Pacific, east to Hawaii and south to New Caledonia. Phylogeny and evolution: Joinvillea was previously included in Flagellariaceae and was only segragated in 1970 on the basis of growth form, indument, leaf morphology and some other anatomical characters. It is a relictual group, c. 89 million years old (stem

POALES

MONOCOTS

Flagellaria indica, along the Daly River, Northern Territory, Australia [136]

Flagellaria neocaledonia, New Caledonia [136]

Joinvillea plicata, New Caledonia [137]

node), and sister to Ecdeiocoleaceae plus Poaceae. Fossils are known from the Upper Miocene of New Zealand. Genera and species: This family includes only the genus Joinvillea, which has four acceped species, although there are likely to be additional cryptic species in New Caledonia and other Pacific islands. Etymology: Joinvillea is named for François Ferdinand Philippe Louis Marie d’Orléans, Prince de Joinville (1818–1900), son of King Louis Philippe of France. As admiral of the French navy he was entrusted with the task of

Joinvillea gaudichaudiana in fruit, New Caledonia [137]

Georgeantha hexandra, female flower, Mt Benia, Western Australia [138]

returning the remains of Napoleon from Saint Helena to Paris in 1840.

138. ECDEIOCOLEACEAE Kwongan-rush family

Ecdeiocolea monostachya, male flowers, Mt Benia, Western Australia [138]

This is a family of rush-like, perennial, bisexual herbs with creeping, hairy rhizomes. They form clumps and can be locally dominant in the vegetation. Leaves are reduced to sheaths that are split on one side to the base. Sheaths surround green culms or inflorescences, which are round in cross-section. Inflorescences are composed of one to three branches terminated by one to four spikelets. Gl umes (bracts) are mostly fertile, and the gender of flowers alternates one to several times in the spikelet. Flowers are unisexual, flattened, and subtended by a glossy, rigid bractlet. The six undifferentiated petals are in two whorls, the outer two

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POALES

Grass family

Stems are jointed with hollow or (rarely) solid internodes. Stems and branches arise from nodes and are subtended by a leaf sheath. Leaves are arranged alternately along the stem, often in two ranks. Leaf bases are sheathing, surrounding the stem internode, usually open on one side, or partially fused. Blades are usually long and narrow, but can be inrolled and linear to broadly ovate. Veins are parallel, in bamboos sometimes with cross-connecting veinlets. The ligule (an appendage at the sheath-blade junction) is thin and membranaceous, sometimes reduced to a line of hairs or absent. Inflorescences are spikelets, organised in lax or contracted spikes, panicles or racemes, occasionally solitary. Spikelets are composed of bracts arranged along a slender axis (a rachilla), the two lower bracts (glumes) without flowers, subtending one to many florets Florets are composed of two bracts enclosing the flower. The outer bract (lemma) is usually more sturdy and enclosing the more delicate inner bract (palea), which is usually two-keeled. Lemma and glumes often have an elongated bristle (awn; see Fig.38 in Glossary). Flowers are unisexual or bisexual and are composed of (zero to) two (or three to many) highly reduced petals (lodicules), stamens and/or a superior ovary. Stamens are usually three, sometimes one, two, six or many, with a hollow elongate filament and a dangling anther. The ovary is unilocular with (one or) two (rarely three) free or basally united styles with feathery elongate stigmas. Styles and anthers are exserted from the florets. Fruits are normally a dry indehiscent nutlet called a caryopsis, sometimes fleshy in bamboos.

Grasses are a large family of annual and perennial, herbaceous and woody plants (bamboos) with often elongate rhizomes.

Distribution: Poaceae occur globally in every habitat and on every continent, including Antarctica and Greenland. The family is represented in the Antarctic Peninsula and throughout the Arctic and also occurs in deserts, forests, dunes, mangroves, salt swamps, brackish and fresh water, and of course in grasslands. A species of Caryophyllaceae (Colobanthus quitensis) and Antarctic hair grass (Deschampsia antarctica) are the only vascular plants found on the Antarctic mainland.

keeled, the inner four flat. Male flowers have a minute pistillode and four or six stamens with slender free filaments and bilocular, dorsifixed anthers that open by slits. Female flowers have staminodes and a superior ovary topped with two or three bushy styles. The fruit is a trilocular capsule or nut. Plants are wind pollinated and survive fires by resprouting from their rhizomes. Distribution: This family is restricted to nutrient-poor, sandy soils in Western Australia. Phylogeny and evolution: Ecdeiocolea was included in Restionaceae before it was recognised as a separate family; a second genus, Georgeantha, was later added. They were separated on the basis of their culm morphology, embryology and pollen morphology. Molecular studies place these as sister to Poaceae. They are estimated to have evolved c. 73 million years ago (stem node). Genera and species: This is a family of two genera and three species, Ecdeiocolea (2) and Georgeantha (1). Uses: There are no known uses, but the family may be of importance for habitat restoration in kwongan soils of Western Australia. Etymology: Ecdeiocolea is composed of the Greek, εκτός (ektos), outside, δένω (déno), to bind and κολεός (koleos), a sheath or vagina.

139. POACEAE

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Christenhusz, Fay & Chase

Phylogeny and evolution: Grasses evolved during the Late Cretaceous in the forest understory. Bamboos evolved woodiness secondarily and were probably the first group of grasses to diversify and form dominant vegetation. The greatest diversification of true grasses occurred during the Tertiary. The Miocene spread and diversification of tundra, prairie and savanna grasses have been linked to the radiation of large grazing mammals around the same time, which evolved hard enamel on their teeth to cope with the increasing number of silica particles (phytoliths) common in grasses. Grasslands became successful because the growing buds were placed below or close to the ground, allowing them to be grazed or burnt. Grassland grasses started spreading during the Eocene, although some South American grasslands may be older (c. 25 million years old). Evolution of grasslands influenced the biosphere and was partly responsible for the rapid decline in atmospheric CO2 during the Oligocene (c. 33 million years ago), just when the first C4 grasses started appearing. Natural grasslands can be considered a carbon and water sink, with a consequence of global cooling in the longer term. However, the high flammability of dry grasses increased the chances of fire allowing the spread of grasslands even further, and increased temperatures favoured C4 grasses, allowing them to invade C3 -dominated grasslands leading to the development of savannas. Genera and species: This large family includes c. 792 genera and c. 11,000 species in 13 subfamilies, although Aristidoideae, Arundinoideae, Centrothecoideae, Chloridoideae, Danthonioideae, Micrairoideae and Panicoideae form a clade and are therefore treated here in a single subfamily (Panicoideae), instead of accepting seven subfamilies: Anomochloöideae – Anomochloa (1) and Streptochaeta (3); Pharoideae – Leptaspis (3), Pharus (7), Scrotochloa (2) and Suddia (1); Puelioideae – Guaduella (6) and Puelia (5); Ehrhartoideae – Chikusichloa (3), Ehrharta (37), Humbertochloa (2), Hygrochloa (2), Hygroryza (1), Leersia (18), Luziola (11), Maltebrunia (3), Oryza (18), Phyllorachis (1), Por tere sia (1), Potamophila (1),

POALES

MONOCOTS

Panicum miliaceum, leaf base and ligule, Provence, France [139]

Anomochloa marantoidea by W. H. Fitch Gigantochloa atter, new shoot, near from Curtis’s Botanical Magazine vol 88 Caraguatatuba, Brazil [139] (ser. 3, vol. 18): t. 5331 (1862) [139]

Coix lacryma-jobi var. ma-yuen, Royal Botanic Gardens, Kew, UK [139]

Scrotochloa urceolata, Mt Datuk, Malaysia [139]

Zea mais, private garden, Kingston upon Thames, Surrey, UK [139]

Oryza sativa ‘Axios’, Helsinki Botanical Garden, Finland [139]

Leymus arenarius, Isokari, Finland [139]

Aegilops speltoides, Ruissalo Briza major, Sicily, Italy [139] Botanical Garden, Turku, Finland [139]

Triticum aestivum, Ruissalo Botanical Garden, Turku, Finland [139]

Plants of the World

207

POALES Prosphytochloa (1), Rhynchoryza (1), Streptogyna (2), Zizania (4) and Zizaniopsis (5); Bambusoideae – Acidosasa (11), Actinocladum (1), Agnesia (1), Alvimia (3), Ampelocalamus (13), Apoclada (1), Arberella (17), Arthrostylidium (32), Arundinaria (3), Athroostachys (1), Atractantha (6), Aulonemia (45), Bambusa (148), Bashania (4), Bonia (5), Buergersiochloa (1), Cathariostachys (2), Cephalostachyum (12), Chimonobambusa (40), Chimonocalamus (16), Chusquea (156), Colanthelia (7), Cryptochloa (8), Cyrtochloa (7), Davidsea (1), Decaryochloa (1), Dendrocalamus (57), Diandrolyra (3), Didymogonyx (2), Dinochloa (37), Drepanostachyum (10), Ekmanochloa (2), Elytrostachys (2), Eremitis (1), Eremocaulon (4), Fargesia (86), Ferrocalamus (1), Filgueirasia (2), Froesiochloa (1), Gaoligongshania (1), Gelidocalamus (12), Gigantochloa (56), Glaziophyton (1), Greslania (4), Guadua (27), Hickelia (4), Himalayacalamus (9), Hitchcockella (1), Holttumochloa (3), Indocalamus (33), Indosasa (22), Kinabaluchloa (2), Lithachne (4), Maclurochloa (1), Maclurolyra (1), Melocalamus (12), Melocanna (2), Merostachys (46), Mniochloa (1), Myriocladus (13), Nastus (25), Neohouzeaua (8), Neololeba (3), Neomicrocalamus (4), Ochlandra (12), Oligostachyum (17), Olmeca (5), Olyra (24), Oreobambos (1), Otatea (8), Oxytenanthera (1), Parabambusa (1), Pariana (29), Parodiolyra (6), Phuphanochloa (1), Phyllostachys (51), Perrierbambus (2), Pinga (1), Piresia (5), Piresiella (1), Pleioblastus (22), Pseudosasa (21), Pseudostachyum (1), Pseudoxytenanthera (4), Racemobambos (19), Raddia (9), Raddiella (8), Rehia (1), Reitzia (1), Rhipidocladum (16), Sarocalamus (3), Sasa (57), Sasaella (1), Schizostachyum (62), Semiarundinaria (7), Shibataea (7), Sinarundinaria (2), Sinobambusa (14), Sinocalamus (6), Sirochloa (1), Soejatmia (1), Sokinochloa (7), Sphaerobambos (3), Sucrea (3), Temburongia (1), Temochloa (1), Thamnocalamus (4), Thyrsostachys (2), Valiha (2), Vietnamocalamus (1), Vietnamosasa (3), Yersinochloa (1), and Yushania (86); Poöideae – Aegilops (23), Agropyron (13), Agropyropsis (1), Agrostis (218), Agrostopoa (3), Aira (8), Airopsis (1), Alopecurus (39), Ammochloa (3), Ammophila (3), Ampelodesmos (1), Ancistragrostis (1),

208

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MONOCOTS

Aniselytron (2), Anisopogon (1), Anthosachne (9), Anthoxanthum (18), Antinoria (2), Apera (5), Aphanelytrum (2), Arctagrostis (2), Arctophila (1), Arrhenatherum (7), Australopyrum (6), Austrofestuca (3), Avena (21), Beckmannia (2), Brachyelytrum (3), Brachypodium (16), Briza (22), Bromus (154), Brylkinia (1), Calamagrostis (251), Castellia (1), Catabrosa (3), Catapodium (4), Chaetopogon (1), Cinna (4), Coleanthus (1), Colpodium (21), Connorochloa (1), Cornucopiae (2), Corynephorus (5), Crithopsis (1), Cutandia (6), Cyathopus (1), Cynosurus (9), Dactylis (2), Danthoniastrum (4), Dasypyrum (2), Deschampsia (40), Desmazeria (3), Diarrhena (5), Dichelachne (9), Dielsiochloa (1), Dissanthelium (14), Dryopoa (1), Dupontia (1), Dupontiopsis (1), Duthiea (3), Echinaria (1), Echinopogon (7), Elymus (191), Eremopoa (5), Eremopyrum (4), Erianthecium (1), Festuca (620), Gastridium (2), Gaudinia (4), Glyceria (40), Graphephorum (2), Hainardia (1), Helictotrichon (92), Henradia (2), Heteranthelium (1), Hierochloe (33), Holcus (10), Hordeleymus (1), Hordeum (36), Hypseochloa (2), Koeleria (46), Koordersiochloa (2), Lachnagrostis (4), Lagurus (1), Lamarckia (1), Leymus (53), Limnas (3), Limnodea (1), Lindbergella (1), Littledalea (4), Loliolum (1), Lolium (8), Lycochloa (1), Lygeum (1), Megalachne (2), Melica (89), Metcalfia (1), Mibora (2), Micropyropsis (1), Micropyrum (2), Milium (6), Narduroides (1), Nardus (1), Nephelochloa (1), Neuropoa (1), Oreochloa (4), Oreopoa (1), Oryzopsis (8), Parafestuca (1), Parapholis (6), Pentapogon (1), Periballia (3), Peyritschia (7), Phaenosperma (1), Phalaris (17), Phippsia (3), Phleum (16), Pholiurus (1), Piptatherum (33), Pleuropogon (6), Poa (533), Podophorus (1), Polypogon (21), Psammochloa (1), Psathyrostachys (11), Pseudodanthonia (1), Pseudosclerochloa (2), Psilurus (1), Puccinellia (109), Relchela (1), Rhizocephalus (1), Rhombolytrum (2), Rostraria (13), Schizachne (1), Sclerochloa (2), Scolochloa (1), Scribneria (1), Secale (9), Sesleria (31), Simplicia (2), Sinochasea (1), Sphenopholis (6), Sphenopus (2), Stephanachne (2), Stipa (486), Taeniatherum (1), Thinopyrum (11), Torreyochloa (5), Tovarochloa (1), Triniochloa (6), Triplachne (1), Trisetaria (15), Trisetum (84),

Triticum (12), Ventenata (8), Vulpia (26), Vulpiella (1), Wangenheimia (1) and Zingeria (5); Panicoideae – Acostia (1), Acrachne (3), Acritochaete (1), Acroceras (24), Adenochloa (14), Aegopogon (4), Aeluropus (6), Afrotrichloris (2), Agenium (3), Alexfloydia (1), Alloeochaete (6), Allolepis (1), Alloteropsis (5), Altoparadisium (2), Amphicarpum (2), Amphipogon (8), Anadelphia (14), Ancistrachne (4), Andropogon (104), Andropterum (1), Anthaenantia (2), Anthaenantiopsis (4), Anthephora (11), Apluda (1), Apochiton (1), Apocopis (16), Aristida (297), Arthragrostis (4), Arthraxon (22), Arthropogon (5), Arundinella (47), Arundo (4), Arundoclaytonia (1), Asthenochloa (1), Astrebla (4), Austrochloris (1), Austroderia (5), Axonopus (71), Baptorhachis (1), Bewsia (1), Bhidea (3), Blepharidachne (4), Blepharoneuron (2), Bothriochloa (36), Bouteloua (27), Brachiaria (119), Brachychloa (2), Bromuniola (1), Buchlomimus (1), Calamovilfa (5), Calderonella (1), Calyptrochloa (1), Canastra (2), Capeochloa (3), Capillipedium (17), Catalepis (1), Cathestecum (4), Cenchrus (26), Centotheca (3), Centrochloa (1), Centropodia (4), Chaetium (3), Chaetobromus (1), Chaetopoa (2) , Chamaeraphis (1) , Chandrasekharania (1), Chasmantium (5), Chasmopodium (2), Chevalierella (1), Chimaerochloa (1), Chionachne (9), Chionochloa (26), Chloris (59), Chlorocalymma (1), Chondrosum (15), Chrysochloa (4), Chrysopogon (48), Cladoraphis (2), Clausospicula (1), Cleistachne (1), Cleistochloa (3), Cleistogenes (13), Coelachne (11), Coelachyrum (6), Coelorachis (21), Coix (3), Cortaderia (20), Cottea (1), Craspedorhachis (3), Crinipes (2), Crypsis (9), Ctenium (20), Cyclostachya (1), Cymbopogon (53), Cynodon (9), Cyperochloa (1), Cyphochlaena (2), Cyphonanthus (1), Cyrtococcum (14), Dactyloctenium (13), Dallwatsonia (1), Danthonia (26), Danthonidium (1), Danthoniopsis (16), Dasychloa (1), Decaryella (1), Desmostachya (1), Dichaetaria (1), Dichanthium (20), Digitaria (261), Dignathia (5), Diheteropogon (4), Dilophotriche (3), Dimeria (60), Dinebra (5), Diplachne (4), Diplopogon (1), Disakisperma (3), Dissochondrus (1), Distichlis (10), Dregeochloa (2), Eccoptocarpha (1), Echinochloa (34), Echinolaena (7), Ectrosia (14), Eleusine (10), Elionurus (15), Ellisochloa (2),

POALES

MONOCOTS

Elymandra (6), Elytrophorus (2), Enneapogon (24), Enteropogon (17), Entolasia (6), Entoplocamia (1), Eragrostiella (6), Eragrostis (413), Eremochloa (13), Eriachne (48), Eriochloa (34), Eriochrysis (10), Erioneuron (2), Euclasta (2), Eulalia (36), Eulaliopsis (2), Eustachys (15), Exotheca (1), Farrago (1), Fingerhuthia (2), Garnotia (30), Geochloa (3), Germainia (9), Gerritea (1), Gilgiochloa (1), Glyphochloa (11), Gouinia (13), Griffithsochloa (1), Gymnopogon (14), Gynerium (1), Habrochloa (1), Hackelochloa (2), Hakonechloa (1), Halopyrum (1), Harpachne (3), Harpochloa (2), Hemarthria (12), Hemisorghum (2), Heterachne (3), Heteranthoecia (1), Heteropholis (4), Heteropogon (6), Hilaria (10), Hildaea (5), Holcolemma (3), Homolepis (5), Homopholis (1), Homozeugos (6), Hubbardia (2), Hubbardochloa (1), Hydrothauma (1), Hylebates (2), Hymenachne (7), Hyparrhenia (56), Hyperthelia (7), Ichnanthus (31), Imperata (11), Indopoa (1), Isachne (92), Ischaemum (84), Iseilema (25), Ixophorus (1), Jansenella (2), Jouvea (2), Kampochloa (1), Kaokochloa (1), Kellochloa (2), Kerriochloa (1), Lasiacis (15), Lasiurus (1), Lecomtella (1), Leptagrostis (1), Leptocarydion (1), Leptochloa (31), Leptocoryphium (2), Leptothrium (2), Lepturidium (1), Lepturopetium (2), Lepturus (12), Limnopoa (1), Lintonia (2), Lophachme (2), Lophatherum (2), Lopholepis (1), Lophopogon (2), Loudetia (25), Loudetiopsis (11), Louisiella (1), Loxodera (5), Lycurus (3), Manisuris (1), Megaloprotachne (1), Megastachya (2), Melanocenchris (3), Melinis (22), Merxmuellera (7), Mesosetum (26), Michrachne (5), Micraira (15). Microcalamus (1), Microchloa (6), Microstegium (26), Miscanthus (16), Mnesithea (4), Molinia (2), Monachather (1), Monelytrum (1), Monocymbium (3), Monodia (1), Mosdenia (1), Muhlenbergia (164), Munroa (5), Myriostachya (1), Neesiochloa (1), Nematopoa (1), Neobouteloua (2), Neostapfia (1), Neostapfiella (3), Neurachne (7), Neyraudia (4), Notochloe (1), Odyssea (1), Oedochloa (9), Ophiochloa (2), Ophiuros (4), Opizia (2), Oplismenopsis (1), Oplismenus (7), Orcuttia (5), Orinus (6), Oropetium (6), Orthacanthus (1), Orthoclada (2), Oryzidium (1), Otachyrium (8), Ottochloa (3), Oxychloris (1), Oxyrhachis (1), Panicum (446), Pappophorum (7), Paractaenium (1), Parahy-

parrhenia (6), Paraneurachne (1), Paratheria (2), Paspalidium (37), Paspalum (333), Pennisetum (83), Pentameris (80), Pentarrhaphis (3), Pereilema (4), Perotis (13), Phacelurus (9), Phaenanthoecium (1), Pheidochloa (2), Phragmites (4), Piptophyllum (1), Plagiantha (1), Plagiosetum (1), Plinthanthesis (3), Poecilostachys (11), Pogonachne (1), Pogonarthria (4), Pogonatherum (4), Pogonochloa (1), Pogoneura (1), Pohlidium (1), Polevansia (1), Polytoca (2), Polytrias (1), Pommereulla (1), Pringlechloa (1), Prionanthium (1), Psammag rostis (1), Pseudanthistiria (4), Pseudechinolaena (6), Pseudodichanthium (1), Pseudopentameris (4), Pseudoraphis (7), Pseudosorghum (2), Pseudozoysia (1), Psilolemma (1), Pyrrhanthera (1), Ratzeburgia (1), Redfieldia (1), Reimarochloa (3), Reynaudia (1), Rheochloa (1), Rhytachne (13), Richardsiella (1), Rottboellia (6), Rugoloa (3), Rytidosperma (73), Saccharum (35), Sacciolepis (25), Sartidia (5), Saugetia (2), Schaffnerella (1), Schedonnardus (1), Schismus (5), Schizachyrium (61), Schmidtia (2), Schoenefeldia (2), Sclerodactylon (1), Scleropogon (1), Scutachne (2), Sehima (5), Setaria (102), Setariopsis (2), Silentvalleya (2), Snowdenia (4), Soderstromia (1), Sohnsia (1), Sorghastrum (20), Sorghum (28), Spartina (15), Spartochloa (1), Spathia (1), Sphaerocaryum (1), Spheneria (1), Spinifex (4), Spodiopogon (16), Sporobolus (184), Stapfochloa (6), Steinchisma (7), Steirachne (2), Stenotaphrum (7), Stereochlaena (4), Steyermarkochloa (1), Stipagrostis (56), Streptolophus (1), Streptostachys (7), Styppeiochloa (3), Swallenia (1), Symplectrodia (2), Taeniorhachis (1), Tarigidia (2), Tatianyx (1), Tenaxia (8), Tetrachaete (1), Tetrachne (1), Tetrapogon (5), Thaumastochloa (8), Thedachloa (1), Thelepogon (2), Themeda (27), Thrasya (22), Thrasyopsis (2), Thuarea (2), Thyridachne (1), Thyridolepis (3), Thysanolaena (1), Toliara (1), Trachypogon (4), Trachys (2), Tragus (8), Tribolium (16), Trichloris (2), Tricholaena (4), Trichoneura (8), Trichopteryx (5), Tridens (16), Trilobachne (1), Triodia (67), Triplasiella (1), Triplasis (2), Triplopogon (1), Tripogon (42), Tripogonella (3), Tripsacum (14), Triraphis (8), Triscenia (1), Tristachya (20), Tuctoria (3), Uniola (5), Uranthoecium (1), Urelytrum (7), Urochloa (15), Urochondra (1), Vaseyochloa

(1), Veldkampia (1), Vietnamochloa (1), Viguierella (1), Vossia (1), Whiteochloa (6), Willkommia (4), Xerochloa (3), Yakirra (7), Yvesia (1), Zaqiqah (1), Zea (6), Zenkeria (5), Zeugites (10), Zonotriche (3), Zoysia (8) and Zygochloa (1). Uses: Poaceae are probably the economically most important family as they are used for food, spice, perfume, building material, biofuel, animal fodder, decoration and sports and recreation. Cereal grains were important in the development of modern human culture. Cultivation of cereal crops (derived from Ceres, the Greek goddess of harvest), allowed humans to become less nomadic and more settled, building houses and protecting their valuable crops against wild animals and human invaders. Grasses are responsible for the formation of the first cities because they permitted the storage of food throughout adverse periods and an excess of food to develop, which permitted professions to arise that were not concerned with food. Wheat (Triticum) provides a fifth of the calories eaten by humans today. It is the primary cereal of temperate regions. Einkorn wheat (T. monococcum) began to be domesticated c. 9000 BC in southwestern Turkey. Even though it was one of the first grains to be cultivated, it is currently rarely grown, usually only as animal food or to make bulgur (cracked wheat). It has a different type of gluten than conventional wheat, which may be of use for people with wheat gluten intolerance. Emmer wheat (T. dicoccum) was first domesticated 10,000 years ago in the Levant and Iran during the Neolithic period, possibly through natural hybridisation of T. dicoccoides and Aegilops speltoides. Emmer is still used to make bread in Italy and Switzerland, and it is used whole in soups in Tuscany. Because of the high fibre content of emmer wheat, it has become popular in the health food industry. Durum wheat (Triticum durum) is also tetraploid and a selection of emmer wheat from Central Europe and the Middle East, which first appeared in cultivation around 7000 BC. It has a high protein content, making it suitable for couscous, dry pasta, gruels, noodles, papadums, pizza, puddings, semolina,

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POALES soups etc. Wild emmer or durum wheat was hybridised with another wild grass (Aegilops tauschii) to produce hexaploid spelt (T. spelta) and modern bread wheat (T. aestivum). Rye (Secale cereale) is known from Neolithic sites in Turkey, but was not domesticated before the Bronze Age in Central Europe (c. 1800–1500 BC). It has been suggested that early wheat fields included a small amount of rye, and that when a wheat crop failed, rye survived and was thus selected. It has been considered inferior to wheat and barley, but because of its greater climatic tolerance, it became the staple crop in the colder climates of Europe. Rye is used for flour, bread, beer, crackers, pumpernickel, vodka, whisky and animal fodder. It can also be cooked whole, and it is low in glutenin, making it suitable for some people with gluten intolerance. Triticale (×Triticosecale) is a hybrid between wheat and rye, which was developed in the 19th century in Scotland and Sweden. It combines the yield and quality of wheat with the disease resistance and environmental tolerance of rye. It has a higher protein and a lower gluten content. It is used for bread and other baked goods and animal feed. Barley (Hordeum vulgare) is most important for the production of beer, whisky and other fermented distilled beverages and animal food. Wild barley (H. vulgare subsp. spontaneum) was first harvested c. 2300 BC in the Middle East, North Africa and Tibet. It was one of the first domesticated grains and is known from a Palaeolithic site in Israel, dated 8500 BC. It has been argued that the availability of barley, along with other domesticatable animals and crops such as wheat and rye, allowed Eurasian civilisations to thrive and conquer other areas. Barley was even used as currency in early times. Barley bread was considered a peasant food and has been largely replaced by potatoes. Asian rice (Oryza sativa) is the most widely consumed staple food, especially in Asia and Latin America. Rice flour has a great number of uses. Rice was independently domesticated in two places, Asian rice (O. sativa) in China c. 10,000 years ago and African rice (O. glaberrima) c. 2,500 years

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ago in the Niger valley of Mali. African rice has become more popular in recent times because it is tolerant of fluctuations in water levels, changes in temperature, pollution and herbivory. However, the grains are more brittle than those of Asian rice, making them difficult to process industrially, and in addition African rice has a lower yield. A hybrid between the two is now marketed as ‘nerica’ (= New Rice for Africa), with great potential. Domestication of maize or corn (Zea mays subsp. mays) occurred 8,700 years ago in seasonal tropical forests in southwestern Mexico, perhaps in the Balsas Valley. It is a selected form of teosinte (Z. mays subsp. mexicana). It is currently the most important cereal crop next to wheat and rice and a staple food in the Americas and Africa. It is the basis for industrial alcohol, babycorn, beer, bourbon, cooking oil, cornflakes, tortillas, tamales, cornflour and polenta. Sugar-rich varieties (sweet corn) are usually grown for human consumption, whereas starchy field corn is used for silage to feed livestock, making it also an important crop for the dairy industry. Even though native to the Fertile Crescent, oats (Avena sativa) were first domesticated in the Bronze Age of Europe. Oats are usually considered a secondary crop, although, like rye, they are highly valued in the colder climates of Europe. Oats are usually rolled or crushed into oatmeal or ground into flour. Oatmeal is eaten as a porridge or made into cookies, digestive biscuits and other baked goods. They also are a major component of breakfast cereals such as muesli and granola. Oats are valued for their capacity to lower cholesterol. Oat cakes are especially popular in Scotland. Oat is also used to feed horses when they need an extra energy boost. Winter oats are grown as a green manure. Samuel Johnson, in his dictionary published in the 18th century, notoriously defined oats as ‘a grain, which in England is generally given to horses, but in Scotland supports the people.’ Of southern African origin, sorghum (mainly Sorghum bicolor, but other species are also used) has been a staple food for millions of people in Africa, Asia and Latin America. It can be grown without additional fertilisers and is the fifth most important cereal crop.

Even though it is used for human consumption in impoverished countries, its main use is for poultry and cattle feed. Millet is a group of small-seeded grasses used as cereal crops and animal fodder. They are important local crops, especially in developing countries because of their short growing season and ability to cope with drought and high temperatures. They encompass grasses from a variety of genera, for example: Guinea millet (Brachiaria deflexa), Job’s tears (Coix lacryma-jobi), Japanese millet (Echinochloa esculenta), Indian barnyard millet (E. frumentacea), burgu millet (E. stagnina), finger millet (Eleusine coracana), tef (Eragrostis tef ), proso millet (Panicum miliaceum), kodo millet (Paspalum scrobiculatum), pearl millet (Pennisetum glaucum), foxtail millet (Setaria italica) and browntop millet (Urochloa ramosa). Fonio is a type of millet that includes species of wild or domesticated grains from the genus Digitaria. White fonio or hungry rice (Digitaria exilis) is a minor crop in West Africa. Even though it has small seeds, it is locally an important food crop because it can mature from seed in less than eight weeks, making it useful in areas prone to drought. Black fonio (D. iburua) is a similar crop, and raishan (D. cruciata) is a minor cereal in India. One of the main crops, if not globally dominant, is sugarcane (mainly Saccharum officinarum, but also S. edule and S. barberi are grown). Originally from tropical Asia, it was first domesticated in New Guinea c. 6000 BC but is now cultivated throughout the tropics. The first production of crystalline sugar occurred in northern India. Sugar was one of the major reasons for European colonisation of the tropics, and the rising demand for sugar in Europe fuelled further land grabs and conversion of tropical forests into cane fields, mainly with the help of slave labour. Sugar formed one of the arms in the triangle trade: Caribbean molasses was shipped to Europe and New England where it was sold for rum or sugar; these profits were used to buy manufactured goods that were shipped to West Africa, where they were exchanged for slaves, who were then transported to the Caribbean to work on the plantations. Sugarcane — and the associated

POALES

MONOCOTS

human addiction to sugar — is thus responsible for the displacement of millions of people and the reshaping of the global map. Currently 80% of all raw sugar is produced by sugar cane. Apart from sugar, sugarcane is used for biofuels (bagasse and ethanol production), molasses or other syrups like falernum and alcoholic drinks like cachaça and rum. Fresh canes are also eaten as a treat. Bamboos are extremely useful in many regards. Young bamboo shoots, common in Asian cuisine, are mainly from Bambusa vulgaris and Phyllostachys edulis, but other species can be eaten. They can be peeled and cooked, stir-fried, pickled or fermented. Sap of bamboos can be tapped and fermented into a sweet drink called ulanzi. Tough stems of bamboos are hollow, flexible and sturdy, making them good for construction and scaffolding poles. They are also used for musical instruments (e.g. panpipes and flutes), furniture, basketry, weaponry, fishing rods, bicycles, fireworks, water desalination, and a great range of everyday utensils. Good quality bamboo is stronger than steel. Bamboo can also be compressed and glued into woodblocks that can be turned into various shapes. Bamboo leaves are sometimes used to wrap food. Bamboo fabrics are made through a long chemical process because bamboo fibres are naturally short. There is a long paper-making tradition in East Asia using bamboo (mostly from Bambusa blumeana and Dendrocalamus asper), and it is a good alternative to wood. Because of the longevity and usefulness of bamboos, several Asian cultures believe that humanity emerged from a bamboo shoot. Another useful grass is the common reed (Phragmites australis), which was traditionally used for thatching of roofs and is still harvested and valued for that purpose, especially in western Europe. Although considered a famine food, young stems of reeds can be dried, ground into powder, made into a dough and roasted. Common reed is also used for basketry, mats, quills and spears. Currently research is being done into its use in compressed form as a building material, insulation for houses and a substitute for traditional wood-based paper. Phragmites

is also employed for natural water cleaning treatment. The plants extract nutrients from the water, which is then mown, composted and used in agriculture. Several grass species are used for perfume or as a spice. Most famous is lemongrass (Cymbopogon citratus and C. flexuosus), which is native to tropical Asia and is often used in local cuisines. It has a citrusy flavour and is added to soups, curries and teas. It is also commonly grown and naturalised in other tropical countries. Lemongrass oil has antifungal properties and is used as a pesticide on plants. Citronella grass (C. nardus) is similar but is usually grown for the insect repellent properties of the oil, commonly used to scent candles. Vetiver (Chrysopogon zizanioides) is mostly cultivated for its fragrant essential oils, present in almost all modern perfumes. It is also sometimes used to flavour foods and drinks. As a tropical cash crop, it also finds use in the prevention of erosion in depleted lands due to its deep roots. Since the early 1980s, Miscanthus giganteus has been used for the production × of biofuel in Europe due to its high biomass, low mineral content and rapid growth. In a single growing season it can reach heights of 3.5 m, which is why it sometimes is called ‘elephant grass’. It is made into ethanol. Rosary beads and necklaces can be made from the hard-shelled seeds of Job’s tears (Coix lacryma-jobi). A cultivar with soft shells called ‘ma yuen’ is used as a cereal in China. Several species are important plants for stabilising soils. In the tropics vetiver, Chrysopogon zizaniodes, is often used, but in temperate zones lyme grass, Leymus arenarius, can be grown for that purpose. Marram or beach grass (Ammophila arenaria) is used to stabilise sand dunes in the Netherlands and elsewhere. Grasses are a major crop for the dairy, meat and wool industries. Grazing animals (predominantly sheep and cows) depend on sufficient amounts of grasses to thrive and produce wool, milk and meat. Cattle and sheep and their associated meadows have changed the landscapes of the world. Another common use of grasses is the lawn. Lawns are composed of one or

a mixture of selected grasses that are kept short. Lawns are a common feature of gardens and parks and are used for aesthetics and recreation. In temperate regions, lawns are usually composed of a mixture of species of Agrostis, Festuca, Lolium and Poa, but in warmer regions Bermuda grass (Cynodon dactylon) or species of Axonopus, Eremochloa, Paspalum, Stenotaphrum and Zoysia are used. Grasses can also cause major problems. Pollen allergy (hayfever) is not unique to grasses (other wind-pollinated species such as pines and birches can also cause it), but grass pollen is a major allergen for numerous people worldwide. Darnel (Lolium temulentum) was a serious weed of cereal fields. Although not poisonous itself, contamination of cereal harvests with seeds of this species infected with the ergot fungus led to many cases of human poisoning. Some grasses become invasive outside their native range and can crowd out native vegetation, spark increased bushfires and prevent forests from regenerating. Several grass species are in cultivation as ornamental plants, especially species of bamboo and Andropogon, Bouteloa, Cortaderia, Eragrostis, Imperata, Melica, Miscanthus, Molinia, Pennisetum, Phalaris, Sasa, and Stipa, to name a few. Etymology: Poa is derived from the ancient Greek word πόα (poa, poie or poia), a pasture grass. Trivia: If you want to see a plant grow, your best bet is to watch a bamboo shoot. It has reported growth rates of over two metres per day. Bamboos flower infrequently, usually at intervals of 65 to 130 years. The longest period between flowering recorded is of Phyllostachys bambusoides, in which all plants of the species worldwide (the species is commonly planted as an ornamental) flowered at about the same time. Production of masses of seeds allows animals to feed on it without harming the population, especially due to the unpredictability of the occurrences of flowering. Finally, bamboo comprises about 99% of the diet of the giant panda, an emblematic species of conservation.

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CERATOPHYLLALES

UNPLACED

CERATOPHYLLALES The placement of Ceratophyllales is not yet certain. Most frequently in recent gene studies, they are sister to the eudicots. Fossils intermediate between Ceratophyllales and Chloranthales are known, making the placement of both orders problematic from a morphological persective.

140. CERATOPHYLLACEAE Hornwort family

212

occur on the same plant and are submersed and subtended by a whorl of eight to 15 linear bracts, which are sometimes mistaken for a perianth, which they lack. Male flowers have three to 50 stamens with a prolonged connective and sessile anthers that open by slits. Female flowers have a single, simple pistil with a superior, unilocular ovary and an elongate style. The fruits are indehiscent, spiny nuts with a single seed and a persistent style. Flowers are pollinated by water, and seeds are dispersed by water currents.

These submersed aquatic, perennial herbs lack rhizomes or roots, but may be anchored in the substrate by specialised branchlets. Three to ten whorled leaves arise from branched, hollow stems and lack stipules and petioles. Leaf blades are simple or one to four times forked, and the dissections have finely toothed margins. The unisexual flowers are formed solitarily in the leaf axils. Staminate and pistillate flowers

Phylogeny and evolution: Recent molecular research has indicated that Ceratophyllaceae are an ancient lineage with no close extant relatives. It has been hypothesised that it is a relict lineage of ancient angiosperms

Ceratophyllum demersum, Turbaco, Bolívar, Colombia [140]

Ceratophyllum demersum, fruit, private garden, Kingston upon Thames, Surrey, UK [140]

Christenhusz, Fay & Chase

Distribution: The family occurs in fresh water bodies worldwide.

diverging early from a lineage leading to modern eudicots. There is fossil evidence that the family was already present during the Cretaceous, c. 115 million years ago. Ceratophyllaceae are placed in an order of their own and are not generally included in eudicots. Genera and species: The single genus in this family, Ceratophyllum, consists of four species. Uses: Species are sometimes grown in aquaria or ponds as oxygenating plants and breeding places for fish. They are sometimes invasive and can be considered a nuisance in waterways and hydroelectric plants. Etymology: Ceratophyllum is derived from the Greek κέρας (keras), a horn, and φύλλων ( fyllon), a leaf. Ceratophyllum demersum in flower, private garden, Kingston upon Thames, Surrey, UK [140]

EUDICOTS The recognition of the existence of this group was one of the novel aspects of the advent of DNA phylogenetics in the angiosperms. Tricolpate pollen (and its derivatives), the most obvious synapomorphy of the eudicots, had been known for a long time, but no one had ever attached a great deal of significance to this trait. Many palynologists had stated that development of this type of pollen was significantly different from that of monosulcate pollen, the other major pollen type, but the groups in which tricolpate pollen exists are so diverse in terms of their morphology that no taxonomist seriously considered that these groups constituted a clade. Even with just the plastid gene rbcL (Chase et al. 1993), this clade was clear. The term eudicot was first used in a different context by Doyle & Hotton (1991), but it was picked up quickly and used in the first broad analyses of DNA data for this clade. It has been proposed that it is not entirely an appropriate term (magnoliids are “true” dicots as well), and the term “tricolpates” has been proposed in its place ( Judd & Olmstead 2004); despite this, the term “eudicots” continues to be widely used. What is clear is that “dicot” is no longer a useful reference, in that it simply now refers to every angiosperm that is not a monocot; these do not form a clade and they include the ANA grade, magnoliids plus Chloranthaceae, Ceratophyllaceae and eudicots. Recognition of eudicots as a clade has given researchers using molecular clock approaches one of their clearest calibration points. Appearance of tricolpate pollen in the fossil record was

abrupt, but there can be no doubt when it is detected that one is then presented with a member of the eudicot clade. Tricolpate pollen first appeared in the fossil record c. 125 million years ago, but when we use a number of other seemingly clear calibration points and estimates of the age of the eudicots, the resulting age estimate for this clade is usually slightly older. It does make sense that if there is abundant tricolpate pollen 125 million years ago, then the clade must have originated before this point, although this pollen evidence is yet to be found. Other characters for the eudicots include usually four- or five-merous f lowers and trends towards fusion of or a reduction in f lower parts. However, the clade is diverse and, in particular, the first several successive sister groups to the rest, such as the families of Ranunculales, have often been included among the magnoliids (Cronquist 1981) due to their numerous stamens and irregular number of perianth parts. Other families, such as Trochodendraceae, have vesselless wood, which must be due to secondary loss, and were often placed among magnoliids for that reason, even though other morphological characters did not coincide with this. Before the use of DNA data such families often presented problems because of their preponderant seemingly primitive traits, even though they had tricoplate pollen. DNA analyses have played a major role in readjusting the thinking of plant systematists in major and significant ways. Many botanists forget that this major shift took place only

since the mid 1990s; it now seems so much a part of our basic thinking that we forget how recently this revolution in thinking took place. Etymology: Eudicot is derived from the Greek words eu (ευ), well or good, dio (δύο), two, and kotylidon (κοτυληδών), seedlobe. General references: Byng JW. 2014. The f lowering plants handbook, a guide to families and genera of the world. Plant Gateway, Hertford. Chase MW, Soltis DE, Olmstead RG, Morgan D, Les DH, Mishler BD, Duvall MR, Price RA, Hills HG, Qiu YL, Kron KA, Rettig JH, Conti E, Palmer JD, Manhart JR, Sytsma KJ, Michaels HJ, Kress WJ, Karol KG, Clark WD, Hedrén M, Gaut BS, Jansen RK, Kim KJ, Wimpee CF, Smith JF, Furnier GR, Strauss SH, Xiang QY, Plunkett GM, Soltis PS, Swensen SM, Williams SE, Gadek PA, Quinn CJ, Eguiarte LE, Golenberg E, Learn GH Jr, Graham SW, Barrett SCH, Dayanandan S, Albert VA. 1993. Phylogenetics of seed plants: an analysis of nucleotide sequences from the plastid gene rbcL. Annals of the Missouri Botanical Garden 80: 528–580. Cronquist A. 1981. An integrated system of classification of flowering plants. Columbia University Press, New York. Doyle JA, Hotton CL. 1991. Diversification of early angiosperm pollen in a cladistic context, pp. 169–195, in: Blackmore S, Barnes SH (eds.) Pollen and spores. Patterns of diversification. Clarendon, Oxford. Judd WS, Olmstead RG. 2004. A survey of tricolpate (eudicot) phylogenetic relationships. American Journal of Botany 91: 1627–1644.

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RANUNCULALES Families 141 to 147 form the order Ranunculales. This order (stem node) is between 140 and 113 million years old. A fossil of 122.6 million years old confirms this age. Most of these families diverged from each other c. 100 million years ago. Eupteleaceae are sister to the other families. Wind pollination and floral nectar spurs have evolved several times independently in Ranunculales. The origin of petals in this order has been discussed extensively. Often the inner whorl of petals of especially Ranunculaceae and Berberidaceae are nectar secreting and derived from stamens, whereas the outer, often sepal-like whorl are considered tepals; where both whorls consist of petallike tepals, gene expression is not well distinguished, whereas in species that have a differentiation between a sepal-like and petal-like whorl the gene expression is similar to that in other eudicots, leading to a discrete calyx and corolla. Because of this in the descriptions below we sometimes refer to sepals and petals when these two whorls are readily distinguishable as such, even though developmentally they may be tepals and stamens.

141. EUPTELEACEAE Asian-elm family

axils of bracts at the base of a leafy shoot. The bisexual flowers lack a perianth; the six to 19 stamens occur in more or less a single whorl, and the eight to 31 free carpels are stalked and also in one whorl. The fruit is composed of several stalked samaras. Distribution: This family occurs in temperate East Asia, northern India, central China and southern Japan.

These deciduous trees and shrubs have spirally arranged leaves without stipules. The leaves are petiolate and undivided, but with a toothed margin and pinnate venation. Inflorescences emerge in spring before the leaves and are composed of six to 12 flowers clustered in

Phylogeny and evolution: Euptelea is sister to the rest of Ranunculales and only shares with other members of the order a few cryptic characters. Previously considered by some authors to be a member of Hamamelidales or to be associated with Trochodendraceae or Cercidiphyllaceae, the simple, wind-pollinated

Euptelea pleiosperma, Royal Botanic Gardens, Kew, UK [141]

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flowers of Euptelea, with no sepals or petals, made systematic placement difficult before the advent of analyses of DNA sequences. This is an old lineage, with a maximum estimated age of c. 135 million years. Genera and species: The single genus in this family is Euptelea, which has two species: E. pleiosperma and E. polyandra. Uses: Both species are sometimes grown as ornamental trees, particularly for their attractive glossy, bright green foliage, which emerges purple and turns red and yellow in autumn. Etymology: Euptelea is Greek, from ευ (eu), good, and πτελέα (ptelea), an elm.

Euptelea polyandra in fruit, Royal Botanic Gardens, Kew, UK [141]

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Pteridophyllum racemosum, Royal Horticultural Soctiety Alpine show, London, UK [142]

Corydalis nobilis, Turku, Finland [142]

Capnoides sempervirens, Helsinki Botanical Garden, Finland [142]

Hunnemannia fumariifolia, private garden, Kingston upon Thames, Surrey, UK [142]

Papaver commutatum, Ani, Turkey [142]

142. PAPAVERACEAE

often present. The stems are herbaceous and usually weak and erect, sometimes vining or almost woody. From latex cells a white, yellow or orange, sometimes watery sap exudes when damaged. Leaves are spirally arranged, rarely appearing opposite or whorled, usually along the stems or, in Hypecoum and Pteridophyllum, in basal rosettes, without stipules. The petioles are often somewhat clasping at the base, and the blades are simple but some lobed to pinnately or ternately divided, usually pinnately, rarely palmately veined. Inflorescences or single flowers are borne at the tip of stems or in axillary bracteate cymes, umbels or racemes; some are scapose thyrses (Pteridophyllum). In Papaveroideae, flower buds are often nodding. Flowers are bisexual, actinomorphic

Poppy family

This family of mostly herbaceous perennials and annuals also includes a few woody genera. Hunnemannia, Dendromecon and Romneya are usually shrubs, and Bocconia species can even be trees. Perennating rhizomes or tubers are

Bocconia arborescens, San Francisco Botanical Garden, USA [142]

or zygomorphic, and the perianth divided into two whorls. The two (or three) sepal-like tepals which are sometimes fused into a cap, soon fall off, often upon opening of the flower. The (two to) four or six petal-like tepals can be all similar or sometimes one or two of them can be extended into a sac or spur, rarely the petals absent (Bocconia, Macleaya) or more (six to 12 in Sanguinaria). Stamens can be two, four, six, eight or numerous, the anthers basifixed, opening by slits, the filaments free or fused, with or without nectaries. The superior ovary is composed of two to 20 fused carpels, topped with a stalked or sessile, variably shaped stigma, which is one of the best characters for species identification. The fruits are usually capsules, sometimes nuts or loments.

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RANUNCULALES Distribution: Papaveraceae are widespread and most diverse in the temperate Northern Hemisphere, but a few species occur in Central and South America and southern Africa. Papaver radicastum can be found at 83ºN latitude, and it and Salix arctica (Salicaceae) are the most northerly distributed vascular plants. Phylogeny and evolution: In some earlier classifications the families Fumariaceae and Pteridophyllaceae were treated separately from Papaveraceae and the three together comprised Papaverales. This order is embedded in Ranunculales, and all members of the former order Papaverales are now treated as a single family with two subfamilies. European Meconopsis cambrica is the type of the genus Meconopsis, but genetically this species falls within Papaver, rather than with Asian Meconopsis species. This and some other findings may result in further taxonomic changes in the circumscription of some genera. The anomalous genus Pteridophyllum is surprisingly most closely related to Hypecoum. The crown group diverged c. 110 million years ago. Genera and species: This family has c. 45 genera and about 775 species divided into two subfamilies: Fumarioideae – Adlumia (1), Capnoides (1), Ceratocapnos (3), Corydalis (c. 400), Cryptocapnos (1), Cysticapnos (4), Dactylicapnos (18), Dicentra (c. 12), Discocapnos (1), Ehrendorferia (2), Fumaria (c. 50), Fumariola (1), Hypecoum (33), Ichtyoselmis (1), Lamprocapnos (1), Plat ycapnos (3), Pseudofumaria (2), Pteridophyllum (1), Rupicapnos (7), Sarcocapnos (4) and Trigonocapnos (1). Papaveroideae – Arctomecon (3), Argemone (23), Bocconia (10), Canbya (2), Cathcartia (6), Chelidonium (1), Dendromecon (2), Dicranostigma (5), Eomecon (1), Eschscholzia (c. 10), Glaucium (c. 25), Hesperomecon (1), Hunnemannia (2), Hylomecon (3), Macleaya (2), Meconella (3), Meconopsis (c. 40), Papaver (c. 80), Platystemon (1), Roemeria (3), Romneya (2), Sanguinaria (1), Stylomecon (1) and Stylophorum (2).

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Uses: Poppy seeds (mostly Papaver somniferum and P. rhoeas) are commonly used as a condiment. A paste of ground poppy seeds and sugar is used in Central and Eastern European patisserie. Poppy seeds are a traditional ingredient of breads, bagels and other baked goods. Opiate drugs derived from the opium poppy (Papaver somniferum), including codeine, heroin and morphine, are widely used in medicine as analgesics. Opium poppies were cultivated in Mesopotamia before written history, and images of them appear on 6,000-year-old Sumerian artefacts. Papaver somniferum was associated with several ancient deities, including Demeter, goddess of fertility and agriculture in Greek mythology. Native to Anatolia, opium gave its name to the Turkish city of Afyonkarahisar (meaning ‘opium black castle’), and until the 1960s that region of Turkey was a major producer of raw opium. Opium became infamous due to the Opium Wars between China and Britain and France in the 19th century, when China wanted to prevent import of the drug into China by western traders. Currently there is a huge illicit trade in opiates, fuelling wars and social unrest in Central Asia, and it has a major social cost resulting from problems related to addiction. Poppy seeds used in baking contain small amounts of opiates. The yellow juice of greater celandine (Chelidonium majus) has been used as a wart remedy. Commercially, bloodroot (Sanguinaria canadensis) is used in products for removing moles and in dental hygiene. The root of Sanguinaria yields a red dye that is popular in Native American handicrafts. Many familiar garden plants belong to the family; e.g. Corydalis (birdin-a-bush), Dicentra (western bleeding hearts), Lamprocapnos (eastern bleeding heart), Pseudofumaria (yellow corydalis), Eschscholzia (Californian poppy), Macleaya (plume-poppy), Meconopsis (blue poppy), Papaver (poppy) and Romneya (matilija or tree poppy). Etymology: Papaver is the Latin name for a poppy or poppy seed, referring to pappa, milk, i.e. the latex exuded from the plant.

143. CIRCAEASTERACEAE Witch’s-star family

This is a family of annual and perennial herbs. In the annual Circaeaster the cotyledons are persistent in mature plants, and in perennial Kingdonia a slender rhizome is formed. Leaves are either simple, rosulate and borne on an elongated hypocotyl (Circaeaster) or single, long-petiolate and palmately arranged (Kingdonia). The veins are flabellate-pinnate, (dichotomously) forking. The bisexual flowers are solitary or in fascicles in leaf axils. The two, three, (four), five or six (rarely seven) tepals are Circaeaster agrestis, China (BX) [143]

Kingdonia uniflora, near Emei Shan, Sichuan, China (CD) [143]

RANUNCULALES

EUDICOTS

persistent or not. Stamens are one, two, or (three to) five to eight, and staminodes, if present, can be eight to 13. The anthers have two pollen sacs. Ovaries are superior and composed of one to nine free carpels, with or without a style. The fruits are indehiscent nutlets. Distribution: These enigmatic plants are found in patchy populations in montane habitats from India (Kumaun) through Nepal to western and central China. Phylogeny and evolution: The two genera differ in many characters, and some taxonomists therefore prefer to recognise each in a separate family. However, molecular results show a close relationship between the two, and the species share characters of venation and anatomy. The genera diverged c. 80 million years ago. Circaeasteraceae are most closely related to Lardizabalaceae. Genera and species: This family includes two genera each with a single species: Circaeaster agrestis and Kingdonia uniflora. Etymology: Circaeaster is derived from the Greek goddess of magic, Κίρκη (Circe), known for her vast knowledge of drugs, herbs and witchcraft, and Latin aster, a star.

144. LARDIZABALACEAE Zabala-fruit family

This family consists mostly of lianas, rarely shrubs. The alternate leaves are palmately compound or (in the case of the shrub Decaisnea) pinnate. The three to many leaflets are stalked. The inflorescences are essentially racemose, but sometimes they appear as cymes or umbels or have sessile solitary flowers. The unisexual flowers are usually combined in mixed inflorescences (with the female flowers

Decaisnea fargesii in fruit, Royal Botanic Gardens, Kew, UK [144]

Akebia longeracemosa, National Botanic Gardens of Ireland, Glasnevin [144]

at the base of the inflorescence), but in South American genera (Boquila, Lardizabala) the male and female flowers occur on different plants. Flowers have three or six petal-like sepals. The six petals are absent or strongly reduced and gland-like, petaloid in Lardizabala. The male flowers are smaller than the female flowers and have six stamens and rudimentary carpels. Female flowers have superior free carpels, often three, but can be irregular in number. The fruits are one to several round or sausage-like berries with a leathery skin and sweet slimy flesh in which the black or brown shiny seeds are embedded. Distribution: This disjunctly distributed family is found in temperate East Asia (Kashmir to northern Vietnam, China, Taiwan, Japan) and southern South America (Chile, Juan Fernández Islands). Phylogeny and evolution: Lardizabalaceae were previously thought to be related to or part of Berberidaceae or Menispermaceae. They are closest to the latter together with Circaeasteraceae. Their relationship to Berberidaceae is more distant. Sargentodoxa is sister to the rest of Lardizabalaceae and sometimes segregated as Sargentodoxaceae, but it has many similarities to Lardizabalaceae and is thus maintained in that family here. The current distribution of Lardizabalaceae is widely disjunct, fossils being known from Europe and North America, but the relationship between the Chilean and East

Stauntonia libera (KWJ12218), Crûg Farm Plants, Wales, UK [144]

Asian species is not old enough to warrant a vicariant hypothesis. The two genera in South America are most likely derived from a more recent long-distance dispersal event. Genera and species: Lardizabalaceae include seven genera and c. 40 species: Akebia (6), Boquila (1), Decaisnea (2), Lardizabala (1), Sargentodoxa (1), Sinofranchetia (1) and Stauntonia (c. 28). Uses: In its native Japan, young shoots of ‘akebi’ (Akebia quinata) are used in vegetable tempura. It is commonly grown in gardens in the temperate zones for its exotic appearance and fragrant flowers and naturalises in North America and New Zealand. Some other species, particularly of the genera Akebia, Decaisnea and Stauntonia, are grown in more specialist horticultural collections. The sweet fruit pulp of all species is edible, but especially Lardizabala (zabala fruit) and Akebia are found in local markets in Chile and China, respectively. Fruits of other species are locally consumed, aiding dispersal when seeds are spat out along the path. Etymology: Lardizabala is named for the philosopher Miguel de Lardizábal y Uribe (1744–1824) from Tlaxcala, Mexico, who studied geology and history at the Botanical Garden of Madrid, Spain. He later became a politician and as Minister to the Indies in 1814 he tried to stop aspirations of independence in the Spanish colonies of America, leading to his imprisonment in 1815.

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145. MENISPERMACEAE Moonseed family

EUDICOTS

to male flowers, but sometimes dimorphic and then female flowers with fewer petals, with or without staminodes. The ovary is composed of one, three, six or more (to 21) free or rarely fused carpels. Fruits are drupes, the seeds often with a curved embryo (hence the common name moonseed). Distribution: These occur mostly in Old and New World tropical lowland rainforests, but some are subtropical or warm temperate in North America and East Asia.

These are predominantly lianas, but some are herbs, shrubs and small trees. They usually grow terrestrially (rarely epiphytically), and stems are vining or erect, usually unarmed, sometimes with spines (Antizoma). Phylloclades are found only in Cocculus balfourii. Leaves have petioles but lack stipules, and the petioles are thickened at both ends, allowing leaves to turn towards the light. Blades are usually simple, sometimes lobed, often peltate at the base, with palmate or pinnate venation. Inflorescences are borne in axils or terminate leafless twigs and are usually many-flowered racemes or panicles, sometimes cymes or flowers solitary. The unisexual (rarely bisexual), actinomorphic or zygomorphic flowers have three to 12 free or fused sepals that are in whorls of three. Petals are one to six, sometimes absent, and free or fused. Male flowers have free or fused stamens that can be three to six, rarely one or two or up to 40. Female flowers are usually similar

Phylogeny and evolution: The family is estimated to have diverged from its sister clade c. 124 million years ago, the two subfamilies diverging during the Late Cretaceous, with Laurasian diversification and distribution c. 70–60 million years ago. Palaeocene fossils are known from South America. Genera and species: Menispermaceae comprise 71 genera and c. 440 species: Abuta (32), Albertisia (17), Anamirta (1), Anisocycla (3), Anomospermum (6), Antizoma (2), Arcangelista (2), Aspidocarya (1), Beirnaertia (1), Borismene (1), Burasaia (5), Calycocarpum (1), Carronia (4), Caryomene (4), Chasmanthera (2), Chlaenandra (1), Chondrodendron (3), Cissampelos (20), Cocculus (8), Coscinium (2), Curarea (4), Cyclea (29), Dialytheca (1), Dioscoreophyllum (3), Diploclisia (2), Disciphania (c. 25), Echinostephia (1), Elephantomene (1), Eleutharrhena (1), Fibraurea

(2), Haematocarpus (2), Hyperbaena (19), Hypserpa (8), Jateorhiza (2), Kolobopetalum (4), Legnephora (5), Leptoterantha (1), Limacia (3), Limaciopsis (1), Macrococculus (1), Menispermum (2), Odontocarya (31), Orthogynium (1), Orthomene (4), Pachygone (9), Parabaena (6), Parapachygone (1), Penianthus (4), Pericampylus (3), Platytinospora (1), Pleogyne (1), Pycnarrhena (9), Rhaptonema (4), Rhigiocarya (3), Sarcolophium (1), Sarcopetalum (1), Sciadotenia (19), Sinomenium (1), Sphenocentrum (1), Spirospermum (1), Stephania (36), Strychnopsis (1), Synclisia (1), Syntriandrium (1), Syrrheonema (3), Telitoxicum (6), Tiliacora (22), Tinomiscium (1), Tinospora (33), Triclisia (10) and Ungulipetalum (1). Uses: The South and Central American genus Chondrodendron is the source of the muscle relaxant and arrow poison curare. Species of Abuta, Curarea, Sciadotenia and Telitoxicum in South America and ipos (Anamirta, Cocculus, Coscinium and Tinospora) in Asia have also been used by local tribes as arrow or fish poison. Picrotoxin, used as a parasiticide in modern medicine, is derived from the Indomalaysian Anamirta. A yellow dye derived from the stems of Fibraurea is used in China and India. Etymology: Menispermum is derived from the Ancient Greek μενε (mene), the moon, and σπέρμα (sperma), seed, in reference to the curved seeds.

Stephania brachyandra, female flowers, Kunming Botanical Garden, China [145]

Cocculus balfourii, Royal Botanic Gardens, Kew, UK [145]

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Chondodendron tomentosum, New York Botanical Garden, USA [145]

Menispermum canadense, Ruissalo Botanical Garden, Turku, Finland [145]

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EUDICOTS

Berberis buxifolia, Royal Botanic Gardens, Kew, UK [146]

Berberis haematocarpa in fruit, Rancho Santa Ana Botanical Garden, California, USA [146]

Diphylleia cymosa, Royal Botanic Gardens, Kew, UK [146]

Nandina domestica, Kunming Botanical Garden, China [146]

Epimedium wushanense, Royal Botanic Gardens, Kew, UK [146]

Sinopodophyllum hexandrum, Royal Botanic Gardens, Kew, UK [146]

146. BERBERIDACEAE

of six to nine, free, petal-like sepals in two or three whorls and six free petals that may be hooded, pouched or spurred. Nectaries are sometimes present. The six stamens have two thecae that open by valves or slits. When touched by an insect, the stamens of some taxa (notably some Berberis species) move quickly towards the style, effecting pollen placement on an insect. The superior ovary has one carpel with a terminal, often persistent style (when a style is present). The fruit is a berry, capsule, follicle or utricle with one to many seeds.

from each other c. 90 million years ago. Three subclades can be recognised in Berberidaceae, represented by three wellsupported subfamilies, but how these are related to each other is not certain. Nandina is morphologically distinctive and has been placed in its own family in the past, but it has some similarities to Caulophyllum. Mahonia is included in Berberis, the distinction between the two genera being vague. Aceranthus is merged with Epimedium, and Vancouveria is sister to this genus. Plagiorhegma is a synonym of Jeffersonia, and Podophyllum has been shown to be polyphyletic, resulting in the acceptance of Dysosma.

Barberry family

Berberidaceae include evergreen and deciduous, perennial herbs, shrubs and sometimes small trees. Stems are erect and woody or wholly or partially underground and rhizomatous or tuberous, with or without prickles. The alternate or opposite leaves are simple or pinnately or ternately compound, sometimes with stipules. Venation is pinnate or palmate. The terminal or axillary flowers are solitary or in fascicles, racemes, spikes, umbels, cymes or panicles. The bisexual flowers are radially symmetrical and sometimes have bracts. The perianth is sometimes absent, but is usually composed

Distribution: Berberidaceae occur in temperate climates worldwide, with woody genera (such as Berberis) more diverse in tropical mountains and the temperate regions of the Southern Hemisphere, and herbaceous genera being more diverse in the northern continents. Several genera (Achlys, Caulophyllum, Diphylleia and Jeffersonia) have a disjunct distribution in East Asia and North America. Phylogeny and evolution: Berberidaceae form a clade with Ranunculaceae, separating

Genera and species: This is a family of 14 genera and c. 700 species in three subfamilies. Berberidoideae – Berberis (c. 600), Ranzania (1); Nandinoideae – Caulophyllum (3), Gymnospermium (9), Leontice (3) and Nandina (1); Podophylloideae – Achlys (3), Bongardia (1), Diphylleia (3), Dysosma (c.10), Epimedium (c. 55), Jeffersonia (2), Podophyllum (2), Sinopodophyllum (1) and Vancouveria (2). Plants of the World

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RANUNCULALES Uses: Fruits of barberry (Berberis vulgaris), American barberry (B. canadensis), holly grape (B. repens), Texas mahonia (B. swaseyi), calafate (B. heterophylla and B. microphylla), michay (B. darwinii) and algerita (B. haematocarpa) are high in vitamin C and sometimes made into preserves or used in cooking. A yellow dye was historically extracted from barberry plants, and the fine wood was used for toothpicks. Berberis species are alternative hosts of black stem rust also affecting wheat and other cereals, and eradication of Berberis has been advocated as a control measure for this economically destructive disease since at least the 17th century in Europe and the 18th century in North America. An extract of Podophyllum is used in some laxative preparations. Several genera are important in horticulture, especially Berberis (barberry and mahonia), Epimedium (fairy wings or horny goat weed) and Nandina (sacred bamboo), many of which are highly valued plants for hedging or the woodland garden. Nandina domestica is believed to be extinct in the wild and to only have survived due to cultivation for centuries in temple gardens in East Asia. Etymology: Berberis is the Latinised form of the Arabic word ‘alburbaris’ (‫ )سيرب رابلا‬for the plant.

147. RANUNCULACEAE Buttercup family

This family includes mostly perennial, annual, sometimes aquatic herbs, woody vines and short shrubs. Leaves are alternate (rarely opposite), simple, three-parted or palmately, pedately or once or twice pinnately compound and usually lack stipules. Flowers can be terminal or axillary, solitary, or in

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racemes, cymes or panicles, usually with bracts. The usually bisexual, regularly symmetrical f lowers (actinomorphic or zygomorphic) have a perianth, with variable numbers of parts (sometimes absent) that is differentiated into sepals and petals or all whorls petal-like, often pentamerous. Segments are usually free, but can be clawed, spurred or hooded. Stamens are usually numerous and arranged in spirals or whorls. The usually free carpels are numerous and whorled. Fruits are usually nuts, follicles or berries, sometimes with elongated plumes that are formed by the persistent styles. Most species are insect-pollinated, but some are pollinated by wind or hummingbirds. Distribution: These plants are found in temperate regions worldwide, extending into the tropics with a few species. They are missing from Antarctica and desert regions of Africa and Australia. Clematis and Ranunculus are among the most widespread genera of flowering plants. Phylogeny and evolution: The crown node has been estimated to be c. 50 million years old. A 125–122 million year old (Early Cretaceous) fossil, Leefructus, was found in China and has been assigned to this clade, which, if correct, may provide different insights on eudicot evolution. Eocaltha, 77 million years old, from the Mexican Cretaceous, and Paleoactaea, 58 million years old, from the Late Palaeocene are similar to modern members of Caltha and Actaea, respectively. The evolution of Delphinium probably occurred around the same time as the diversification of bumblebees, 40–25 million years ago. Members of Circaeasteraceae and Paeoniaceae were previously placed in or near this family. Glaucidium, previously placed in Paeoniaceae or in its own family, is close to Hydrastis; together, they are sister to the rest of Ranunculaceae (or form a grade). These two genera do share morphological similarities, but in some analyses the two are not found in the same clade and thus separate subfamilies have been proposed; the similarities between the two have been interpreted as plesiomorphic for the family.

Molecular studies have resulted in major reorganisations of genera in this family. For instance Anemone has been expanded with Barneoudia, Hepatica, Knowltonia, Miyakea, Oreithales and Pulsatilla, but it was recently found that this interpretation was due to incorrect outgroup sampling and in fact these genera form a grade leading up to Clematis. Thus Anemone needs to be divided, accepting Anemonidium, Eriocapitella, Hepatica, Pulsatilla and an expanded Knowltonia. Beckwithia, Ceratocephala, Coptidium, Ficaria, Krapfia, Kumlienia, Laccopetalum and Myosurus are part of a clade including Ranunculus and these genera are merged, but Oxygraphis, Paroxygraphis and Halerpestes are maintained due to the unexpected position of Trautvettera in this clade (formerly in Thalictroideae). Cimicifuga and Souliea are part of Actaea, and Aconitella and Consolida are embedded in Delphinium. Even though Delphinium is polyphyletic with regard to Aconitum, these genera can be maintained when Staphisagria is accepted. Megaleranthis has been merged with Trollius. Anemonella and Paropyrum are now placed in Thalictrum, and Enemion is better placed in Isopyrum. Genera and species: Ranunculaceae are a family of 43 genera and c. 2,346 species in five subfamilies: Glaucidioideae – Glaucidium (1); Hydrastidoideae – Hydrastis (1); Coptidoideae – Coptis (15) and Xanthorhiza (1); Ranunculoideae – Aconitum (c. 300), Actaea (27), Adonis (26), Anemoclema (1), Anemone (c. 75), Anemonidium (14), Anemonopsis (1), Asteropyrum (2), Beesia (2), Calathodes (3), Callianthemum (14), Caltha (12), Clematis (c. 332), Delphinium (c. 350), Eranthis (9), Eriocapitella (6), Halerpestes (c. 10), Hamadryas (6), Helleborus (21), Hepatica (5), Knowltonia (28), Nigella (22), Oxygraphis (5), Paroxygraphis (1), Pulsatilla (c. 33), Ranunculus (c. 625), Staphisagria (3), Traut vetteria (1) and Trollius (31); Thalictroideae – Aquilegia (80), Dichocarpum (20), Isopyrum (2), Leptopyrum (1), Metanemone (1), Paraquilegia (5), Paropyrum (1), Semiaquilegia (1), Thalictrum (c. 250) and Urophysa (2).

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Clematis alpina, private garden, Kingston upon Thames, Surrey, UK [147]

Adonis annua, Royal Botanic Gardens, Kew, UK [147]

Hydrastis canadensis, Sarah Duke Botanical Nigella papillosa near Ronda, Spain [147] Garden, Durham, North Carolina, USA [147]

Pulsatilla slavica, Helsinki Botanical Garden, Finland [147]

Delphinium consolida, Hengelo, the Netherlands [147]

Ranunculus californicus, Point Bonita, California [147]

Glaucidium palmatum, Royal Botanic Gardens, Kew, UK [147]

Anemone nemorosa near Turku, Finland [147]

Xanthorhiza simplicissima, private Helleborus foetidus, Royal Botanic Gardens, Kew, UK [147] garden, Kingston upon Thames, Surrey, UK [147]

Thalictrum aquilegifolium, Helsinki Botanical Garden, Finland [147]

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Uses: Kalonji or kaljeera, Nigella sativa, is used as a spice in baking, although it is toxic if used to excess. Goldenseal (Hydrastis canadensis) has been used extensively by Native Americans as a general medicine and a dye. The plant has been used to treat various ailments, from cancer to ophthalmia. Currently it is used as a natural antibiotic, but it is not sustainably harvested and is therefore threatened in North America. Its international trade is restricted by CITES. Many species are poisonous, and some are deadly; Aconitum species have been

the cause of accidental and intentional poisonings. Despite these unpleasant properties, Ranunculaceae remain among the most popular of garden plants, including Aconitum (monkshood), Actaea (baneberry), Adonis (pheasant’s eye), Anemone (anemone), Aquilegia (columbine), Caltha (marshmarigold), Clematis (traveller’s joy), Delphinium (larkspur), Eranthis (winter aconite), Eriocapitella (Japanese anemone), Helleborus (hellebore), Hepatica (liverleaf), Nigella (love -i n-a-m ist), Pulsat illa (pasquef lower), Ranunculus (buttercup),

Thalictrum (meadow rue) and Trollius (globeflower). Record: Together with a species of Brassicaceae, Ranunculus lobatus, can be found at an elevation of 7,756 m in the Himalayas, the highest elevation at which any seed plant will grow. Etymology: Ranunculus, a name already in use for the plant in classical times, is a diminutive form of the Latin rana, a frog, probably because many species grow in wet places.

PROTEALES Families 148 to 151 comprise Proteales, an unlikely assembly of aquatic herbs, windpollinated trees and shrubs, vines and trees, often with colourful nectar-producing flowers. Sabiaceae have not been found to be a member of Proteales in all analyses, but they share some characters with Proteaceae, such as the nectariferous hypogynous disc. They differ markedly in numbers of floral parts and many other characters, but considering the diversity in the rest of Proteales, Sabiaceae do not add much additional heterogeneity. Characters that are shared among Proteales are the anther connectives extending beyond the anther locules and frequent occurrence of tubular leaf epidermal waxes.

148. SABIACEAE Pao-hua family

Sabia yunnanensis, Guo Ba Yan, Han Bai Yu Shan, Sichuan, China (CD) [148]

Meliosma arnottiana, Royal Botanic Gardens, Kew, UK [148]

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Meliosma dilleniifolia, Royal Botanic Gardens, Kew, UK [148]

These deciduous and evergreen trees, shrubs and woody vines have alternate, simple or once pinnate leaves without stipules. The petioles or petiolules are often pulvinate, and the blades are frequently covered with red glands. Inf lorescences are axillary or terminal, usually cymes or panicles, sometimes the flowers solitary. The bisexual or rarely polygamous-dioecious plants have actinomorphic or zygomorphic flowers that are generally tiny. The usually five sepals are free or fused at the base and are equal or

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Superhydrophobic leaves of sacred lotus, Nelumbo nucifera, Helsinki Botanical Garden, Finland [149]

Nelumbo nucifera, Brooklyn Botanical Garden, USA [149]

Nelumbo nucifera, fruiting, Royal Botanic Gardens, Kew, UK [149]

unequal in size. The usually five petals are equal or the inner two are much reduced. The five stamens are attached to the petals at the base and are often all fertile, or three of them are staminodial. The filaments are filiform or expanded below the anther to form a collar. The anthers have two thecae on either side of a narrow or thickened cup-shaped connective that forms a central pore through which the style grows. The superior ovary is bi- or rarely trilocular. The fruit is a drupe or indehiscent follicle with a single seed.

Genera and species: This family has three genera with about 66 species: Meliosma (c. 40), Ophiocaryon (7) and Sabia (19).

filaments and anthers that open by slits. The connective has an incurved appendage. The superior ovaries are numerous and individually embedded in the flattened top of a turbinate receptacle. The style is short and the stigma nearly sessile. Fruits are indehiscent nuts that are loose in cavities in the receptacle. They are pollinated by insects, usually beetles.

Etymology: Sabia is derived from the Hindi sab-ya, the Indian name for Sabia lanceolata.

149. NELUMBONACEAE Sacred-lotus family

Distribution: Sabiaceae are distributed in warm temperate and tropical Central and South America and East Asia. Phylogeny and evolution: Sabiaceae are sometimes treated as the only family in the order Sabiales, but have recently been found to be sister to the remaining Proteales and included with them. Fossils of Insitiocarpus from the Middle Cretaceous (c. 90 million years old) are believed to be Sabiaceae and Meliosma and Sabia from the Late Cretaceous are also known. The family is estimated to have appeared c. 120 million years ago (stem node). Pollination of Meliosma is remarkable; the anthers open within the bud, enclosed and held under pressure by the staminodes. The bud opens explosively upon rough contact (for instance by a visiting insect), releasing the pollen, although pollen also collects in the broad connectives from where insects can collect it.

This family of perennial aquatic herbs has branched, slender, underground, creeping rhizomes, of which the terminal portions become tuberous late in the growing season. Vegetative parts of the plant have conspicuous air chambers. Leaves arise alternately from the rhizome and are floating or emergent. The petiole is long and warty, the blade round, peltate, and the margin entire. The surface is covered with a layer of water-repellent wax. The bisexual flowers emerge solitarily from the leaf axils and are held above the water surface on a long peduncle. The free petals are numerous, the outermost somewhat reduced, the inner ones larger and more petal-like. The stamens are numerous and have slender

Distribution: The family occurs in temperate and subtropical North America, tropical and temperate southern and East Asia. One species is naturalised throughout the tropics. Phylogeny and evolution: Nelumbonaceae have frequently been included in Nymphaeaceae s.l., although on the basis of the leaf anatomy and flower morphology it had already been suggested that the family must be distantly related. However, gene expression in the flowers of Nelumbo and Nymphaea is remarkably similar. It has been shown by DNA analyses that Nelumbonaceae are most closely related to Platanaceae and Proteaceae, sharing characters of the seed with Proteaceae. Mid Cretaceous fossils known as Nelumbites share the remarkable f lower morphology but have different leaf venation, so this may or may not be associated with this family. An age of over 100 million years is likely for this lineage. Flowers thermoregulate in order to release a scent to attract insects, and the c. 30 ºC temperature rewards visiting insects with a stable environment for mating.

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PROTEALES Genera and species: The family has a single genus, Nelumbo, with three species: N. komarovii, N. lutea and N. nucifera. The last may have to be subdivided on the basis of anatomical characters. Uses: The tubers formed by mature plants of sacred lotus are edible and cultivated as a food crop, especially in tropical Asia. Their seeds are also widely used in Asian cuisine. Nelumbo nucifera is the sacred flower of Buddhism and Hinduism, and it is the national flower of India and Vietnam. Sacred lotus is frequently cultivated in (sub-)tropical water gardens and ponds. The leaves of lotus are superhydrophobic, and the wax of the leaves is now synthetically imitated as a highly waterrepellent wax used in industry and as a paint for cars etc. Etymology: Nelumbo is derived from nelum, the Sinhalese word for the lotus flower.

150. PLATANACEAE Plane-tree family

Platanus racemosa showing flaking bark, Palm Springs, California, USA [150]

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This is a family composed of large deciduous trees, with erect trunks that have smooth bark exfoliating in thin plates to form a mosaic of colours, becoming furrowed when older. Twigs have buds that are hidden by the base of the swollen petiole and often bear simple or compound hairs, the compound ones with whorls of branches, appearing stellate. The alternate, simple leaves are palmately lobed, with three, five or seven lobes or unlobed. The petioles are flanked by sheathing stipules with entire or serrate margins. The leaf bases are cordate, truncate or cuneate, and the blade surface is tomentose with stellate hairs, becoming glabrous with age. The unisexual inflorescences occur on the same plant (monoecious) and are axillary or solitary, crowded into dense heads, and emerge together with the leaves. Male inflorescences are sessile, with one to five, globose heads that soon fall off. Female inflorescences are sessile or stalked, terminal, with one to seven globose heads in pendulous racemes. Individual flowers are usually tri- or tetramerous and minute, the sepals free or fused at the base and the petals vestigial. Male flowers have stamens that are as many as the numbers of sepals, the connective enlarged to a peltate appendage, and pistillodes are sometimes present. Female flowers have three or four staminodes and three to eight free superior carpels that are placed in two or three whorls, with linear styles that have the stigmatic surface on the inner side. Fruits are achenes that are densely crowded in the heads, often Platanus ×acerifolia (P. occidentalis × P. orientalis), Hyde Park, London, UK [150]

persisting on the tree until spring, surrounded by numerous hairs that are basally attached and simple. Flowers are wind-pollinated. Distribution: The family occurs in North America, from Canada and the Great Lakes to central Mexico and Guatemala, southeastern Europe and warm-temperate Asia, south to Laos. Phylogeny and evolution: The family is well represented in the fossil record of North America and Eurasia and was once more widespread across the Northern Hemisphere. The relationship between Platanaceae and Proteaceae may explain why there are so many platanoid leaf fossils in the Southern Hemisphere. Some Proteaceae have wood that is similar to that of Platanaceae, although in general the wood anatomy of the two families is different, which may be due to the different climatic conditions in which these families are found. The family is estimated to have diverged c. 110 million years ago, and fossils of this approximate age, like Platanocarpus, are known. Genera and species: The family includes only the genus Platanus with eight species. Uses: The wood of sycamore (US) or plane (UK) (Platanus) is resistant to splitting, and it is therefore traditionally used to make buttons and butchers’ blocks, but the wood is Grevillea rhyolitica flowers visited by an eastern spinebill (Acanthorhynchus tenuirostris) in the Australian National Botanic Gardens, Canberra [151]

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difficult to work and of limited commercial value. Several species and hybrids are popular shade or avenue trees especially in urban areas because they are tolerant to pollution and respond well to pruning. However, the hairs formed on the new growths can cause irritation and allergic reactions in humans.

or four glands are usually present around the ovary, and these are scale-like or fleshy, sometimes fused. The superior (sometimes semi-inferior) ovary is composed of a single locule, topped by a single simple, persistent style. The fruit is a dehiscent or indehiscent woody or coriaceous follicle, achene, nut or drupe, fused in cones in some cases. Seeds are sometimes winged.

This is a family of creeping to upright shrubs and trees, sometimes appearing herbaceous, but then with persistent woody roots. Roots are often produced in short clusters (proteoid roots, a unique character). Stems are usually covered with short, three-celled hairs. The alternate, or rarely opposite or whorled, leaves are simple or pinnatifid, pinnately or bipinnately compound, rarely palmately so, usually leathery and stiff. They lack stipules and usually have a pinnate venation. The inflorescences are simple or compound, axillary or terminal, racemes, panicles or condensed heads, umbels, corymbs or cones or with solitary flowers. The usually bisexual flowers are zygomorphic or actinomorphic, usually one or two in the axils of bracts, which are sometimes absent. The four petal-like tepals are free or variously fused, and each petal has a slightly expanded valved limb. The four stamens are usually all fertile and oppose the tepals, with the filaments partly or completely fused with these, often forming colourful ‘pollen presenters’, rarely free, the anthers are often sessile on the perianth. Two

Phylogeny and evolution: Proteaceae are known to have been diverse in the Late Cretaceous and Eocene of Australia, and some genera such as Cardwellia and Gevuina may show a distribution related to continental

Leucadendron discolor, San Francisco Botanical Garden, USA [151]

Macadamia integrifolia, Royal Botanic Garden, Sydney, Australia [151]

Persoonia pinifolia, Royal Botanic Garden, Sydney, Australia [151]

Banksia hookeriana, Western Australia [151]

Protea cynaroides, Royal Horticultural Society Garden, Wisley, UK [151]

Telopea speciosissima ‘Corroboree’, Australian National Botanic Garden, Canberra [151]

Etymology: The name comes from πλάτανος ( platanos), the classical Greek name for Platanus orientalis, possibly related to Greek πλάτος (platos), flat.

151. PROTEACEAE Sugarbush family

Distribution: This family has its greatest diversity in the Southern Hemisphere, especially in Australia and southern Africa. Smaller numbers of species are known from Mexico, Central and South America, tropical Africa, Madagascar, India, East and Southeast Asia, Malesia, New Caledonia, New Zealand and Fiji.

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PROTEALES drift, whereas others such as the genus pair Brabejum and Panopsis are certainly a product of more recent long-distance dispersal. Banksia may be c. 60 million years old, and fire may have spurred diversification in this and other Australian genera. Diversification of Proteaceae in the Cape of South Africa may have been more recent than in Australia and is likely a result of edaphic speciation. Some generic reorganisation may be needed in the future. Dryandra has already been included in Banksia, but Grevillea, for example, may have to be expanded to include Hakea and Finschia, and other recircumscriptions of genera are likely when the phylogenetics of Proteaceae become better understood. Genera and species: Proteaceae are a family of 79 genera and about 1,750 species in five subfamilies: Bellendenoideae – Bellendena (1); Persoonioideae – Acidonia (1), Garnieria (1), Persoonia (c. 100), Placospermum (1) and Toronia (1); Grevilleoideae – Alloxylon (4), Athertonia (1), Austromuellera (2), Banksia (169), Bleasdalea (2), Brabejum (1), Buckinghamia (2), Cardwellia (1), Carnarvonia (1), Catalepidia (1), Darlingia (2), Embothrium (1), Eucarpha (2), Euplassa (20), Finschia (3), Floydia (1), Gevuina (1), Grevillea (362), Hakea (149), Helicia (c. 100), Heliciopsis (14), Hicksbeachia (2), Hollandaea (2), Kermadecia

EUDICOTS

(4), Knightia (1), Lambertia (10), Lomatia (12), Macadamia (9), Malagasia (1), Megahertzia (1), Musgravea (2), Neorites (1), Opisthiolepis (1), Oreocallis (1), Orites (8), Panopsis (25), Roupala (33), Sleumerodendron (1), Sphalmium (1), Stenocarpus (21), Strangea (3), Telopea (5), Triunia (4), Turrillia (3), Virotia (6) and Xylomelum (6); Proteoideae – Adenanthos (33), Aulax (3), Beauprea (13), Beaupreopsis (1), Cenarrhenes (1), Conospermum (53), Diastella (7), Dilobeia (2), Eidothea (2), Faurea (c. 15), Franklandia (2), Isopogon (35), Leucadendron (80), Leucospermum (48), Mimetes (13), Orothamnus (1), Paranomus (19), Petrophile (53), Protea (114), Serruria (51), Sorocephalus (11), Spatalla (20), Stirlingia (7), Synaphea (50) and Vexatorella (4); Symphyonematoideae – Agastachys (1) and Symphionema (2). Uses: Seeds of several species can be eaten. Macadamia nuts are perhaps the best known, and Macadamia integrifolia, M. ternifolia and M. tetraphylla are now grown commercially for their seeds, especially in Australia and Hawaii. The delicious and nutritious seeds are also valued in the cosmetic industry, with the oil being considered a botanical alternative to mink oil. Chilean hazel (Gevuina avellana) is commonly consumed in South America and New Zealand. Other genera that produce edible nuts are Floydia prealta (coohoy nut),

Hicksbeachia pinnatifolia (red boppel nut) and Finschia chloroxantha. Nectar of some species is also harvested in traditional societies. Banksia fruit ‘cones’ are woody and sometimes used for carving. Cross-sections of the fruits make attractive decorations. Several species of Banksia, Leucadendron, Leucospermum, Protea and Telopea are popular in the cut-flower industry, and many species are grown as garden ornamentals especially in areas with Mediterranean climates. Warratah (Telopea speciosissima) is the floral emblem of New South Wales, but as a cut flower it is exported as ‘kiwi rose’ from New Zealand. Oldest clone: Lomatia tasmanica is known from a single clone only. All individuals are triploid and sterile, and the plants spread vegetatively. Based on fossil evidence, these clones formed 43,600 or more years ago, and the remaining 500 plants now cover an area of 1.2 km. Even though each individual part of this plant lives for ‘only’ some 300 years, the clone is one of the oldest plants alive. Etymology: Protea is named for Πρωτεύς (Proteus), a half-god of sea and rivers and the oldest son of Poseidon in ancient Greek mythology. Proteus was capable of appearing in many forms, which members of this family do as well.

TROCHODENDRALES This order consists of the single family Trochodendraceae, which has a fossil history dating back to the Late Cretaceous. It was widespread across the Northern Hemisphere, sometimes at high latitudes. Fossils of both extant genera have been known since the Eocene.

Tetracentron sinense, China (YN) [152]

152. TROCHODENDRACEAE Wheel-tree family

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This family of evergreen trees and shrubs has (near) vessel-less wood. Leaves are spirally arranged in false whorls or on elongate branches, without stipules or with a stipule covering the bud and later fused with the petiole. The blades are simple and pinnately or palmately veined. The terminal racemes or panicles bear bisexual flowers subtended by two to five bracts (Trochodendron) or catkinlike spikes in whorls of four (Tetracentron). Flowers have a broadened receptacle and

BUXALES

EUDICOTS

lack a perianth (Trochodendron) or have four sepals only (Tetracentron). In Trochodendron the 40–70 stamens are placed in several whorls around the (four to) six to 17 carpels in a single, laterally fused whorl. In Tetracentron only four stamens surround the four basally fused carpels. The fruit is composed of the laterally fused follicles that open on the inside with short slits. Seeds are winged or not. Distribution: This family is distributed in temperate and subtropical East Asia, from

Japan south to Taiwan and southern China, Nepal and northwestern India.

the Northern Hemisphere (as Nordenskioldia) from the Late Cretaceous.

Phylogeny and evolution: Trochodendraceae are the sole member of the order Trochodendrales; in some previous classifications, each genus was placed in its own family. Previously the genera were of unclear relationships and were sometimes linked with Cercidiphyllaceae (Saxifragales) or Eupteleaceae (Ranunculales). Now restricted to isolated populations in East Asia, fossils are known from around

Genera and species: The family has two genera, each with a single species: Tetracentron sinensis and Trochodendron aralioides.

Tetracentron sinense, China (YN) [152]

Etymology: Trochodendron is derived from Greek τροχός (trochos), a wheel, and δένδρων (dendron), a tree, in reference to the stamen arrangement.

Trochodendron aralioides, Brooklyn Botanical Garden, USA [152]

BUXALES This order diverged probably around 120 million years ago. It consists of the single family Buxaceae.

153. BUXACEAE Box family

Buxaceae are trees, shrubs and rarely herbs that are usually glabrous, sometimes hairy, the hairs simple. Leaves are opposite or alternate and simple, lack stipules and are pinnately veined, but sometimes have three prominent veins from the base. Inf lorescences are bracteate axillary or terminal spikes, racemes or cymes, often congested. The unisexual flowers have an undifferentiated perianth (tepals) or none. Male flowers usually have four free tepals

(none in Haptanthus) and four to six (to many) usually free stamens (two fused stamens in Haptanthus), the filaments absent to enlarged and showy, the anthers opening by lengthwise slits or valves; a pistillode is sometimes present. Female flowers are usually few and larger than the male flowers, with four to six tepals (none in Haptanthus). The superior ovary is composed of two to three fused carpels that are topped with two or three styles. Fruits are loculicidally Plants of the World

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BUXALES dehiscing capsules or drupes, the styles usually persistent and showy. Distribution: The family has a patchy distribution across the world, from the southern USA through Mexico, the Caribbean and the Andes to the Azores, western and southern Europe, North Africa, the Caucasus, Sub-Saharan Africa, Madagascar, southern India and Sri Lanka, the Himalayas to Southeast and East Asia, the Philippines and western Indonesia. Phylogeny and evolution: Madagascan Didymeles and Honduran Haptanthus are sometimes placed in their own families. Didymeles is probably sister to the other genera; Haptanthus is now known to be sister to just Buxus. When Haptanthus was first

EUDICOTS

described, it could not be assigned to a family, but it is clear now that it belongs to Buxaceae. Fossil Didymeles is known from New Zealand. Crown group Buxaceae are at least 111 million years old, a date corroborated by fossils from the Early Cretaceous. The family was widespread in the Northern Hemisphere during the Tertiary. Genera and species: The family has six genera with c. 65 species: Buxus (c. 40), Didymeles (2), Haptanthus (1), Pachysandra (3), Sarcococca (13) and Styloceras (6). Uses: The fine grain of boxwood (Buxus) is good for wood carving, particularly for decorative storage boxes, hair combs and chess pieces. It was the preferred wood for woodblock book printing, and it still is

commonly used to make musical instruments such as string instruments and bagpipes. Buxus sempervirens is commonly planted for garden hedging and topiairy, Sarcococca is planted for winter scent, and Pachysandra terminalis is a common evergreen ground cover in shady gardens. Box branches as a substitute for palm fronds are blessed with holy water in the Catholic church on Palm Sunday. Etymology: Buxus is the classical Latin name for B. sempervirens, which in turn is derived from Ancient Greek πυξός (puksos), the classical name for a box tree. Formerly more widespread in England, B. sempervirens is commemorated in place names including Box Hill (where it still occurs) and Bix Bottom (where it is now absent).

Buxus sempervirens, Box Hill, UK [153] Buxus obtusifolia, near Malindi, Kenya [153]

Sarcococca hookeriana, Royal Botanic Gardens, Kew, UK [153]

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Haptanthus hazlettii, Honduras (AS) [153]

Pachysandra terminalis, Royal Botanic Gardens, Kew, UK [153]

GUNNERALES

EUDICOTS

GUNNERALES Families 154 and 155 form the order Gunnerales. The two genera in this order have been merged into one family by some authors, but their differences are so great that it is deemed better to maintain them in separate families. They share some wood anatomical characters (hydathodes), stipules, excretion of resin and lack of a perianth, but one is often a giant herb of humid habitats, the other a resurrection shrub of arid places, and the hydathodes and stipules are not of similar ontogeny. The age of this lineage (stem node) has been suggested to be somewhere between 118 and 77 million years.

154. MYROTHAMNACEAE Resurrection-shrub family

These aromatic, glabrous shrubs are unisexual (dioecious). Their narrowly winged main branches produce short lateral vegetative shoots that carry the opposite, sessile leaves, which can survive extensive desiccation. The leaves are obtriangular, broadly sheathing at the base and surrounded by a tooth-like stipule. The leaves are flabellate and plicate with all veins emerging from the sheathing base and at their distal end dentate. The catkin-like inflorescences terminate short shoots. The flowers occur in triads at the base of the

Myrothamnus flabellifolius, South Africa (NH) [154]

inflorescence, solitary above, with the flowers or triads opposite each other and subtended by a bract. The sessile flowers sometimes have two bracteoles and two to four scale-like tepals, sometimes tepals absent, usually present in terminal flowers. The male flowers have three to eight stamens, with short filaments and basifixed anthers that open by lengthwise slits. Female flowers have a superior ovary composed of three to four partially fused carpels and free styles and recurved stigmas. The fruits are capsules that open from the tip exposing the numerous small seeds.

Genera and species: Myrothamnus is the sole genus in this family and has two species: M. flabellifolius and M. moschatus. Etymology: Myrothamnus is composed of the Greek μύρων (myron), a scent, and θάμνος (thamnos), a shrub.

155. GUNNERACEAE Giant-rhubarb family

Distribution: This family is restricted to arid regions of southern and tropical East Africa and western Madagascar. Phylogeny and evolution: Myrothamnus is the only woody resurrection plant. Its leaves dry out completely during the dry season, but turn green in a short time after exposure to water. It is most closely related to Gunneraceae, but there is no fossil record.

This family includes usually perennial, rarely annual, rhizomatous and stoloniferous small to gigantic herbs. They have a close association with the nitrogen-fixing cyanobacterium

Gunnera pilosa, Ecuador [155]

Gunnera prorepens, Beth Chatto Gardens, UK [155]

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GUNNERALES Nostoc in their stems and roots. Their leaves are alternate and placed spirally at the tip of the rhizome, emerging in the axils of stipule-like scale-leaves. The blades have a toothed margin, palmately forking venation that is prominent on the lower surface, and a finer reticulate tertiary venation. Inflorescences are usually branched racemes, simple racemes or spikes or panicles. The numerous actinomorphic, bisexual flowers cover the inflorescences. They have two, sometimes three sepal-like tepals and the same number of petal-like tepals that are usually hooded, or the inner whorl sometimes absent. The usually two (rarely one) stamens are fused with the petals. The inferior ovary is composed of two fused carpels forming one locule. The fruits are nut-like drupes. Distribution: This family occurs in mesic habitats in tropical mountains and temperate areas of the Southern Hemisphere, from Mexico to Patagonia and the Falkland Islands, East African mountains from Ethiopia to the

Tetracera indica, Lazarus Island, Singapore [156]

Tetracera loureiri in fruit (WA) [156]

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Cape, northern Madagascar, the Malesian Archipelago, Tasmania, New Zealand and Hawaii. Phylogeny and evolution: The distinctive pollen has been found in sediments as old as the Early Cretaceous and was known at that time from all southern continents, leading some to conclude that this family may have a distribution related to vicariance events after the separation of Gondwana. However, its present-day occurrence on volcanic islands like Juan Fernández and Hawaii indicates that long-distance dispersal is also common. The annual Gunnera herteri is sister to the rest of the genus. Gunneraceae were in the past often associated with Haloragaceae or Saxifragales. They are certainly inedible and not related to rhubarb (Rheum, Polygonaceae) to which the common name refers. Mutualistic association: Glands on the stem just below the leaves secrete mucilage Dillenia suffruticosa, Lazarus Island, Singapore [156]

that contains various sugars attracting the cyanobacterium Nostoc. The motile hormogonia of Nostoc enter the plant via the glands and once inside lose their mobility and form heterocysts; they often do not photosynthesise. Nostoc fixes nitrogen, and in return Gunnera provides Nostoc with sugars. Genera and species: Gunneraceae include only Gunnera, with 63 species. Uses: Gunnera is frequently planted as a pond margin plant in gardens in temperate climates. Etymology: Gunnera is named in honour of Norwegian bishop and botanist Johan Ernst Gunnerus (1718–1773), who was the first to describe the basking shark and published the Flora Norvegica. Like his contemporary Linnaeus, who named the genus for him, he also made an expedition to Lapland and described the habits of the Saami people in detail. Dillenia philippinensis, Singapore Botanical Garden [156]

Hibbertia acerosa, Mt Benia, Western Australia [156]

SAXIFRAGALES

EUDICOTS

DILLENIALES This order has been difficult to place and consists of the single family Dilleniaceae with an estimated age of 114 million years (stem node).

156. DILLENIACEAE Guineaflower family

This family includes trees, shrubs, woody climbers and a few herbs. The alternate (rarely opposite) spirally arranged leaves are simple, rarely pinnatisect or pinnately compound and petiolate. There are no stipules, and petioles are sometimes winged. Blades are often toothed, and venation is pinnate with strong, parallel secondary veins that end in teeth. Inflorescences are racemes, panicles or cymes, but frequently the flowers are formed singly in the leaf axils. The bisexual, rarely unisexual, flowers are mostly actinomorphic, occasionally slightly zygomorphic (Hibbertia) or strongly zygomorphic (Schumacheria). They have three or four to five, sometimes up

to 18, sepals that are leathery or succulent and persistent in fruit. The two or three to five, sometimes to seven free petals are crumpled in bud. Stamens are usually numerous (or one to ten) and free or fused at the base and then in fascicles. Anthers are basifixed and open by lengthwise slits or apical clefts or pores. Staminodes are also often present. The superior ovary is composed of two to seven (or up to 20) free or partially fused carpels, tipped with free styles terminated by the stigma. Fruits are follicles (sometimes compound), berries, or capsules often enclosed by fleshy or leathery sepals. Seeds are often arillate. Distribution: This pantropical family extends into warm-temperate Asia and Australia. Phylogeny and evolution: This is the sole family in the order Dilleniales, which have proved difficult to place in eudicot classification, even with the aid of whole plastid genome sequences and many low-copy nuclear genes. The stem age may be c. 115 million years old, but the crown group diverged c. 52 million years ago. A subfamilial classification has been proposed,

but not all genera are yet placed so it is therefore not adopted here. Previously, the family was viewed as the type of subclass Dilleniidae, but they have no close relatives based on molecular studies, and as mentioned have defied a wellsupported assignment to any major clade of eudicots, which makes their assignment to their own order appropriate. Genera and species: Dilleniaceae include 12 genera with c. 300 species: Acrotrema (10), Curatella (3), Davilla (18), Didesmandra (1), Dillenia (60), Doliocarpus (40), Hibbertia (c. 120), Neodillenia (3), Pachynema (7), Pinzona (1), Schumacheria (3) and Tetracera (c. 44). Uses: Fruits of Dillenia crenatifolia, D. indica and D. salomonensis are edible. Some species of Dillenia and Hibbertia are grown as garden ornamentals. Etymology: Dillenia was named by Carolus Linnaeus in honour of German botanist Johann Jacob Dillenius (1684–1747), who hosted Linnaeus in Oxford in 1736.

SAXIFRAGALES Families 157 to 171 form the diverse order Saxifragales, which are mostly distributed in the temperate zones and rare in the tropics. Relationships within the order have been problematic, and this may be the result of rapid radiation over a period of 3–6 million years during the Mid Cretaceous.

157. PERIDISCACEAE Ringflower family

Peridiscaceae are small trees and large shrubs with alternate, simple leaves. They have stipules in the leaf axils and petioles with a pulvinus at the tip immediately below entire or crenulate leaves. Flowers are formed in axillary clusters of racemes or spikes, sometimes reduced to one or two racemes. Bisexual flowers are regularly symmetrical with four to seven free sepals. The African genera have five petals, whereas the South American species lack them. Stamens are

numerous and arranged around the nectar disc, or (in Medusandra) only ten stamens are present, of which five are staminodial and the disc absent. The superior ovary can appear half inferior due to the size of the disc. A unilocular ovary consists of three or four carpels. The one-seeded fruit is a berry in American Peridiscus and a capsule in the African genera. Distribution: This family is distributed in the Guiana Shield and in West and Central Africa. Plants of the World

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Whittonia guianensis, holotype specimen collected by B. A. Whitton in Guyana in 1959 (Kew Herbarium) [157]

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Medusandra richardiana, Mokoko Forest Reserve, Cameroon (CD) [157]

Medusandra richardiana, Mokoko Forest Reserve, Cameroon (CD) [157]

Paeonia obovata in fruit, Helsinki Botanical Garden, Finland [158]

Paeonia delavayi, private garden, Hengelo, the Netherlands [158]

Paeonia cambessedesii, Royal Botanic Gardens, Kew, UK [158]

Phylogeny and evolution: Peridiscaceae had been restricted to the American genera Peridiscus and the enigmatic Whittonia, but were expanded in APG III to include the African Medusandra (formerly Medusandraceae) and Soyauxia, which in earlier classifications had been placed in Passifloraceae or the now defunct Flacourtiaceae (Malpighiales). The placement of Peridiscaceae in Saxifragales was surprising, given that this order is dominated by families from temperate regions. Some association with Paeonia has been found in molecular analyses. Whittonia is only known from its type specimen collected near the

Kaieteur Falls in Guiana and has not been recollected. It is suggested that this species may be extinct, or, because it shares many characters with Peridiscus, it may have been confused with that genus in the field.

158. PAEONIACEAE

Christenhusz, Fay & Chase

Peony family

Genera and species: This small family has four genera with 11 species: Medusandra (2), Soyauxia (7), Peridiscus (1) and Whittonia (1, possibly extinct). Etymology: Peridiscus is composed of the Greek περί (peri), around, and δίσκος (diskos), a ring.

This family of perennial herbs and shrubs has simple and branched stems, growing from short

SAXIFRAGALES

EUDICOTS

Phylogeny and evolution: In the past Paeonia was included in Ranunculaceae, especially associated with Glaucidium, or it was thought to be related to Dilleniaceae. Neither of these families made a good morphological fit, and molecular studies now place this family in Saxifragales in which an association with Peridiscaceae in some cases has been found.

woody rhizomes and often has tuberous roots. They produce stipule-like scales that clasp the winter bud on the stem. Leaves are alternate, long-petiolate and pinnate, ternate or twice ternately compound or dissected. Terminal inflorescences are usually composed of solitary flowers, but sometimes there are two or three (up to six). Flowers are bisexual with a spirally arranged perianth composed usually of four to six free sepals (sometimes fewer or more) that are unequal in size and more or less leathery. The five to 13 free petals (sometimes four or up to 25 in some cultivars) are large and showy. Stamens are free, numerous, usually 50–200 or so. Anthers are basifixed, upright and opening by lengthwise slits. Staminodes are not present, but the intrastaminal glands are sometimes interpreted as such. The superior ovary is composed of usually five (sometimes less or more) free carpels. Follicle-like fruits open adaxially exposing the large rounded seeds with an outer integument that can be showy and aril-like.

Uses: Seeds of Paeonia officinalis were reputedly eaten in Mediaeval England during Lent. Several species are of medicinal importance in the Himalayas. Many cultivars of especially P. lactiflora and P. suffruticosa are popular garden plants around the temperate zones. The largest species in the genus, P. ludlowii, is also sometimes grown and can develop into a shrub 3.5 m tall.

Distribution: The genus can be found in temperate climates in western North America south to northwestern Mexico, and it is widespread in Eurasia from the Mediterranean through Anatolia, the Caucasus, north to Siberia and the Kola Peninsula, east to Japan and Korea through China and the Himalayas.

Etymology: Paeonia is derived from the classical Greek name for the peony plant, παιονία (paionia), which in turn means ‘of Paion’. The deity Παιών (Paion or Paean) was physician to the gods in Greek mythology, and the name refers to its medicinal use in classical times.

159. ALTINGIACEAE Sweetgum family

Genera and species: Paeonia is the only genus and has 33 species. This family of deciduous and evergreen trees has alternate leaves that are usually arranged in a plane (distichous). Leaves have a simple or three-, five- or seven-lobed blade and linear stipules at the base of the petiole. They have a pleasant aroma when crushed and are pinnately or palmately veined. Unisexual f lowers lack a perianth and are wind pollinated. Male inflorescences are globular or cylindrical many-flowered heads that are grouped in terminal racemes or panicles, each male flower with one to four basal bracts and four to ten (or many) stamens that have anthers opening by lengthwise slits or valves. Female inflorescences are ball-shaped (condensed panicles) of five to 30 flowers formed subterminally on long peduncles or in the lower parts of bisexual inflorescences. Staminodes are sometimes present in female flowers and resemble needles. The (semi-) inferior bicarpellate ovary is surrounded by rudimentary scales (bracts). The fruit is a woody capsule called a ‘gumball’, the carpels opening to release the narrowly winged seeds. Distribution: The family has a relictual distribution in eastern and southern North America, Mesoamerica, southern Turkey and Greece, India, Southeast Asia, China, Taiwan, Peninsular Malaysia, Sumatra and Java.

Liquidambar styraciflua, Royal Botanic Gardens, Kew, UK [159]

Liquidambar formosana, young fruit, Mt Huangshan, Anhui, China [159]

Phylogeny and evolution: Altingiaceae were widespread across the Northern Hemisphere during the Tertiary but went extinct in many localities during the Pleistocene ice ages. They were formerly often included in Hamamelidaceae, to which they are not closely related, as subfamily Liquidambaroideae. Previously two genera were recognised,

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SAXIFRAGALES but apart from the lobed deciduous leaves Liquidambar is similar to Altingia in most characters, and the genera also hybridise. Phylogenetic studies also indicated that there is a single genus. Genera and species: The family is now considered to have only one genus, Liquidambar, with 15 species.

EUDICOTS

Etymology: Altingia is named for Willem Arnold Alting (1724–1800), Governor-General of the Netherlands East Indies. Altingia has been synonymised with Liquidambar, a name that is composed of the Latin liquidus, liquid, and Arabic ambar, amber or balm, referring to the sweet resinous sap.

160. HAMAMELIDACEAE Witch-hazel family

Uses: Levant storax (Liquidambar orientalis) produces a sweet resin, which was the balm of Gilead in the Bible. Resin of sweetgum (L. styraciflua) is antiseptic and used in skin products. Both of these species produce good timber, and the latter is a popular street tree away from its native range due to its spectacular autumn colour. Ransamala (L. excelsa) also produces good timber. Distylium pingpienense in fruit, Kunming Botanical Garden, China [160]

This family includes evergreen and deciduous shrubs and trees. Their leaves are usually alternate, rarely subopposite or opposite, and distichously or spirally arranged. Petioles are flanked by stipules that are usually paired and free, sometimes solitary with an enclosing bud (Mytilaria) or absent (Rhodoleia). Leaf blades are simple and pinnately veined or palmately (tri-)lobed and veined. Axillary or terminal inf lorescences are usually bracteate spikes or heads, rarely racemes, thyrses or panicles. Bisexual or unisexual flowers are often flanked by bracteoles and usually actinomorphic, rarely zygomorphic (Rhodoleia), the floral cup shallow to urnshaped, sometimes lacking. The four or five (sometimes ten) sepals are usually persistent, but absent in some species. Petals are absent or four or five and usually ribbon-like. The

Loropetalum chinense var. rubrum, Royal Botanic Gardens, Kew, UK [160]

Fothergilla major, Bodnant Estate, North Wales, UK [160]

Corylopsis chinensis, Royal Botanic Gardens, Kew, UK [160]

Molinadendron sinaloense, University of California Botanical Garden, Berkeley, USA [160]

Hamamelis virginiana, near Madison, Wisconsin, USA [160]

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EUDICOTS

four, five or numerous free stamens are usually all fertile, but can be arranged in two whorls with a staminodial inner whorl. The basifixed anthers open by one two valves or a simple lengthwise slit with a protruding connective. Disk scales are sometimes present between stamens and carpels. The inferior to superior ovary is composed of two carpels that are apically free, each topped by a style and stigma. Fruits are septicidally or loculicidally dehiscent, woody or leathery capsules with two or four valves. Seeds are winged or not. Distribution: This family is found in eastern North America, Mesoamerica, northern South America, eastern and southern Africa, the Comoros, Madagascar, Turkey, the southern Caspian region, and from the Himalayas through China to Korea and Honshu and south though Southeast Asia, Malesia, northern Australia (Queensland) and several Pacific islands. Phylogeny and evolution: The crown age of the family has been estimated at 26 million years old, but with a much older fossil record: Allonia decandra was described from the Cretaceous of the USA, and many fossils are known from the Early Tertiary. Four subfamilies (Disanthoideae, Exbucklandioideae, Hamamelidoideae and Mytilarioideae) are sometimes recognised, but several genera are not yet placed because they are poorly known and are in need of critical revision.

Dicoryphe (12), Disanthus (1), Distyliopsis (7), Distylium (10), Embolanthera (2), Eustigma (2), Exbucklandia (2), Fortunearia (1), Fothergilla (2), Hamamelis (4), Loropetalum (3), Maingaya (1), Matudaea (2), Molinadendron (3), Mytilaria (1), Neostearia (1), Noahdendron (1), Ostrearia (1), Parrotia (1), Parrotiopsis (1), Rhodoleia (c. 10), Sinowilsonia (1), Sycopsis (3) and Trichocladus (6). Uses: Distylium and Exbucklandia produce a valuable fine-grained timber used for furniture and turning. Witch hazel (Hamamelis virginana) was used for eye lotions in the past and is still used as a treatment for bruising. Many species are grown as garden ornamentals, especially Corylopsis and Hamamelis; the latter has sweetly scented flowers appearing before the leaves in late winter and spring. Etymology: Hamamelis (αμαμελής) is the classical Greek name for the wych elm, Ulmus glabra (Ulmaceae), but is now used for witch

Distribution: The family is restricted to China and Japan, a relictual distribution.

hazel only.

161. CERCIDIPHYLLACEAE Caramel-tree family

Genera and species: A family with 26 genera and c. 86 species: Chunia (1), Corylopsis (7), Cercidiphyllum magnificum, male flower, Royal Botanic Gardens, Kew, UK [161]

This is a family of deciduous trees with two branch types: long vegetative shoots with opposite leaves and short vegetative or reproductive shoots with a single leaf. Leaves are heart-shaped, petiolate with the latter flanked by two small stipules that fall off quickly. Blades are simple with palmate venation. Inflorescences appear before the leaves and are unisexual fascicles in heads. Each flower is usually subtended by a bract, but a perianth is lacking. Male inflorescences are sessile with four or more flowers that are difficult to separate, the inflorescence with 16–35 stamens, perhaps one to 13 per flower. Anthers are basifixed and red, opening by lengthwise slits. Female inflorescences are shortly stalked with two to eight flowers. The ovary is composed of a single naked carpel, tipped with a long-papillate stigma. The fruit is a follicle that opens away from the inflorescence axis.

Phylogeny and evolution: Cercidiphyllaceae were widely distributed across the Northern Hemisphere during the Tertiary. A great number of fossil Cercidiphyllaceae are known from the Palaeocene and Upper Cretaceous. They have an isolated position, but with Daphniphyllaceae form the sister of Hamamelidaceae. Genera and species: The sole genus in this family, Cercidiphyllum, has two similar species: C. japonicum and the smaller C. magnificum.

Cercidiphyllum japonicum, female flowers, Ruissalo Botanical Garden, Turku, Finland [161]

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SAXIFRAGALES Uses: Katsura (Cercidiphyllum japonicum) is the largest tree species in Japan. Its wood is used to make boards for the Japanese board game go. It is a valuable ornamental, the leaves in autumn turning yellow with a caramel-like scent. Etymology: Cercidiphyllum is composed of classical Greek κέρκης (kerkis), a poplar tree, and φύλλων ( fyllon), a leaf. Cercis is the ancient name used by Theophrastus to describe the Judas tree, Cercis siliquastrum (Fabaceae); the leaves of Cercidiphyllum resemble those of Cercis.

162. DAPHNIPHYLLACEAE Laurel-leaf family

EUDICOTS

bracteate racemes of unisexual flowers. The small calyx is composed of three or six parts and sometimes persistent. Petals are absent. Male flowers have five to 12 (–18) stamens in one whorl, with short filaments and moonshaped anthers that open laterally along their length and have an exserted connective. Female flowers sometimes have five to ten staminodes, but these are sometimes absent. The bilocular, superior ovary has a short, two-branched style. The fruit is an ovoid or ellipsoid, tuberculate or rugose, often glaucous fleshy drupe with a hard stone. Distribution: The family is distributed in southern India, Sri Lanka, East and Southeast Asia, and from the Himalayas throughout Indochina and Malesia to the Solomon Islands. Phylogeny and evolution: Daphniphyllaceae have been difficult to place in the past, and associations have been made with a variety of families such as Balanopaceae, Euphorbiaceae and Hamamelidaceae. The last relationship is now confirmed by molecular data.

These are evergreen, unisexual trees and shrubs with alternate leaves that are often clustered or nearly verticillate at the apex of branches. The petiolate simple leaves lack stipules and are often leathery and glaucous beneath. Inflorescences are axillary, solitary

Daphniphyllum macropodum, male flowers, Royal Botanic Gardens, Kew, UK [162]

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Genera and species: The family has a single genus, Daphniphyllum, which has c. 30 species. Uses: The Ainu people of Japan and Siberia used to dry and smoke the leaves of Daphniphyllum humile like tobacco.

Daphniphyllum humile, female flowers, Crûg Farm Plants, Wales, UK [162]

Etymology: Daphniphyllum is composed of Greek δάφνη (dafne), a laurel bush, and φύλλων ( fyllon), a leaf, from the resemblance of the leaves to Laurus nobilis (Lauraceae).

163. ITEACEAE Sweetspire family

This family is composed of trees and shrubs that are sometimes lax climbers. They are usually evergreen, sometimes deciduous, and their leaves are alternate, simple with minute stipules and distinct petioles. Blades are usually pinnately veined and glandularserrate, rarely entire. Inf lorescences are many-flowered terminal or axillary racemes or panicles that are often in groups of two or three, or few-flowered corymb-like cymes. The bisexual flowers are actinomorphic. The five sepals are fused basally into a short, conical tube around the base of the ovary, forming a hypanthium. Five petals are placed between the sepals on the hypanthium and are persistent, triangular or clawed. The five

Daphniphyllum chartaceum, Kunming Botanical Garden, China [162]

SAXIFRAGALES

EUDICOTS

Itea rhamnoides, Moodie Mountains, South Africa (CD) [163]

Itea yunnanenis, Nichols Arboretum, Ann Arbor, Michigan, USA [163]

Ribes sanguineum, planted in a garden in Giethoorn, the Netherlands [164]

stamens are inserted on an annular nectar disc, with short filiform (Itea) or broad and apically toothed filaments (Pterostemon). The anthers are dorsifixed, open by lengthwise slits, and in Itea have a globular protrusion of the connective at the tip. The nearly superior or mostly inferior ovary is composed of two or five fused carpels and is bi- or pentalocular. It is topped with single fused (Pterostemon) or two fused or free (Itea) styles, with capitate, globular stigmas that are coherent in flower, separating in fruit (Itea) or the stigma shallowly five-lobed (Pterostemon). The often woody capsules have a persistent perianth and open by two or five valves. Distribution: Iteaceae are found in temperate eastern North America, southwestern North America (Oaxaca, Mexico), southeastern Africa and temperate and tropical East and

Itea virginica, Hortus botanicus, Leiden, the Netherlands [163]

Ribes roezlii, Royal Horticultural Society Show, London, UK [164]

Southeast Asia, from the Himalayas to China, Japan, Java and the Philippines.

164. GROSSULARIACEAE Gooseberry family

Phylogeny and evolution: The family is known from c. 90 million years old fossil flowers of the Late Cretaceous of North America and from Tertiary fossil pollen from Europe and North America. Iteaceae have been included in Grossulariaceae or Escalloniaceae, but molecular results place Itea sister to the Mexican genus Pterostemon in core Saxifragales. Genera and species: This bigeneric family has 21 species: Itea (18) and Pterostemon (3). Etymology: Itea (ιτέα) is Greek for willow, given to this genus on account of the rapid growth of some species and the glandular serrate leaf margins, similar to those of willows.

Bisexual, rarely unisexual shrubs, that are usually deciduous, sometimes (semi-) evergreen make up this family. They can be upright, creeping or laxly climbing and are frequently covered in simple or ternate spines. Their alternate, simple leaves are usually petiolate with dry, brown, fimbriate stipules. Leaf blades are usually trilobed or

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SAXIFRAGALES subpalmately lobed or cleft, and normally have toothed margins, rarely subentire. Venation is palmate, usually with three main veins. Inflorescences are terminal or axillary racemes, sometimes corymbs or flowers solitary. Flowers are usually bisexual (unisexual in R. diacanthum), and the perianth is placed on a floral tube that is wholly or partially fused with the ovary at the base. The five (rarely four) sepals are fused at the base and can be green or coloured and petallike. The five (rarely four or absent) petals are distinct, green or coloured. The five (rarely four) stamens are all fertile (rarely all staminodial in female f lowers), with filiform filaments that are free or fused to the hypanthium but distinct from each other. Anthers are basifixed and open by lengthwise slits. A well-developed five-lobed nectar disc surrounds the tip of the ovary. The partly or completely inferior ovary is composed of two fused carpels forming one locule and two free or fused styles on top, with two stigmatic papillose branches. The fruit is a soft berry crowned by a persistent perianth, often covered with hairs, prickles or glandular hairs. Distribution: The family is widely distributed in the temperate zones of the Northern Hemisphere, in North America, south to the mountains in Central America and the Andes in South America, throughout temperate, boreal and montane Europe, the Atlas Mountains in North Africa and temperate and montane northern and East Asia. They jump into the Southern Hemisphere in southern South America. Phylogeny and evolution: Grossulariaceae have in the past been part of a broadly circumscribed and heterogeneous Saxifragaceae or Grossulariaceae s.l. (members of which are now placed in Celastraceae, Escalloniaceae, Iteaceae, Montiniaceae, Phyllonomaceae and Tetracarpaeaceae). A relationship with other woody Saxifragales has been assumed, but with no support phytochemically or embryologically. Molecular analyses place Grossulariaceae as sister to herbaceous Saxifragaceae s.s., which is supported by many morphological characters.

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EUDICOTS

Genera and species: The sole genus in Grossulariaceae is Ribes with c. 150 species. Uses: Many species of Ribes are cultivated for their fruits, especially blackcurrant (R. nigrum), redcurrant (R. rubrum etc.) and gooseberry (R. uva-crispa); superior cultivars and hybrids between these and other Ribes species are now generally grown, rather than the wild types. Sour when fresh, the fruits are widely used in cooking and for juice and jam. Redcurrants are rich in pectin and the juice is sometimes mixed with other fruit to ensure a good set in jam. They can also be made into cordial (e.g. Ribena) and syrups, and are an important ingredient of rødgrød, a kissel-like dessert from Denmark. Minor fruit crops of Ribes include whitecurrant (an albino form of redcurrant), greencurrant (a Finnish form of blackcurrant), American blackcurrant (R. americanum), granite gooseberry (R. curvatum), prickly gooseberry (R. cynosbati), Worcesterberry or Western black gooseberry (R. divaricatum), jostaberry (a complex hybrid between R. divaricatum, R. nigrum and R. uva-crispa) and golden currant (R. odoratum). Some species such as R. grossularoides, R. sanguineum and R. speciosum are solely grown as garden ornamentals and their fruit is inedible. Etymology: A grossulus is a small unripe fig in classical Latin, a word later applied in old French as groseille, although the etymology is also probably tied in with Frankish krusil, Old Dutch kroesel and German kruselbeere, all meaning a wrinkled berry, possibly all from the same Indo-European root. Grossularia is a later synonym of Ribes, which is a Latinised form of Semitic ribas, acid-tasting.

165. SAXIFRAGACEAE Saxifrage family

These are usually perennial herbs, rarely annual or biennial, and often have perennating rhizomes. Leaves are usually formed in alternate basal rosettes, sometimes along the inflorescence stems and then also alternate or sometimes opposite; they are usually simple, rarely pinnately or palmately compound, and the margin can be entire or deeply lobed or cleft, crenate or dentate. Leaves are usually petiolate with stipules. Inflorescences are bracteate racemes or cymes. Bisexual or unisexual f lowers are actinomorphic or sometimes zygomorphic, and the perianth is placed on a hypanthium that can be free or partly fused with the ovary (producing a semi-inferior ovary). The sepals are usually five, sometimes three or up to ten, and fused with the hypanthium. The usually five (sometimes four, six or absent) petals are clawed, sometimes cleft at the tip or finely dissected. The five or ten stamens are free and have basifixed anthers that open by lengthwise slits. The inferior or semi-inferior ovary is composed of two, sometimes three, carpels that are fused at the base, and each carpel is topped with a stylodium and capitate stigma. The capsular or follicular fruit typically has numerous small seeds. Distribution: Saxifragaceae are widespread across the Northern Hemisphere, in North America south to central Mexico, throughout Europe and temperate and subtropical Asia, and North Africa, the Andes and the mountains of Ethiopia, Luzon and New Guinea. Phylogeny and evolution: The age of Saxifragaceae has been estimated to be between 54 and 38 million years old, but fossil data are inconclusive, since pollen records for the family may also refer to the similar Hydrangeaceae or other families now excluded from Saxifragaceae. A 90-million year old Late Cretaceous fossil, Tylerianthus, from North America may be a member of the stem lineage of Saxifragaceae, although the authors of that paper indicated it was related to both Hydrangeaceae and Saxifragaceae, which at that time were still thought to be closely related. Nevertheless, the fossil appears to be related to Saxifragaceae s.s.

SAXIFRAGALES

EUDICOTS

Astilbe thunbergii, Royal Botanic Gardens, Kew, UK [165]

Bergenia crassifolia var. pacifica, Ruissalo Botanical Garden, Turku, Finland [165]

Saxifragaceae used to include a great number of unrelated taxa, such as Parnassia (now in Celastraceae), Escalloniaceae, Hydrangeaceae and Vahliaceae. Mitella has been found to be polyphyletic, representing several distinct lineages and Saxifraga is paraphyletic. The taxonomy has not yet been resolved. Micranthes used to be part of Saxifraga, but it does not fall in the clade that includes typical Saxifraga. Generic recircumscription is greatly needed.

Saxifraga aizoides, above Wasdale Head, Lake District, UK [165]

in the temperate zones, especially Astilbe (false buck’s-beard), Bergenia (elephantears), Darmera (Indian rhubarb), Heuchera (coralbells), Mukdenia, Rodgersia, Saxifraga (saxifrage, londonpride), Tellima (fringecups) and Tiarella; some are houseplants such as the piggyback plant (Tolmiea menziesii) and mother-of-thousands (Saxifraga stolonifera).

Genera and species: The family has 35 genera and c. 640 species: Astilbe (25), Astilboides (1), Bensoniella (1), Bergenia (10), Bolandra (2), Boykinia (6), Brachycaulos (1), Cascadia (1), Chrysosplenium (c. 55), Conimitella (1), Darmera (1), Elmera (1), Heuchera (c. 35), Hieronymusia (1), Jepsonia (3), Leptarrhena (1), Lithophragma (10), Micranthes (c. 70), Mitella (20), Mukdenia (1), Oresitrophe (1), Peltoboykinia (1), Rodgersia (5), Saniculiophyllum (1), Saxifraga (c. 370), Saxifragodes (1), Saxifragopsis (1), Suksdorfia (2), Sullivantia (3), Tanakaea (1), Telesonix (2), Tellima (1), Tetilla (1), Tiarella (3) and Tolmiea (2).

Carnivory: Carnivory of plants with glandular hairs was studied by Charles Darwin, who observed that the glands of meadow saxifrage (Saxifraga rotundifolia) and Pyrenean saxifrage (S. umbrosa) were able to absorb a range of substances. Some saxifrages have glands that are capable of trapping insects, and these same glands have absorptive properties. The exudates from the glands have not been demonstrated to have digestive properties, and it is unlikely that these plants are true carnivores because their habitat preferences do not appear to be those associated with the classic cases of carnivory. However, there is always a chance that an insect is caught and products of its decaying body could be absorbed by the plant via the glands or the roots.

Uses: The leaves of Chrysosplenium oppositifolium (golden saxifrage) and Saxifraga nelsoniana (Nelson’s saxifrage) are eaten fresh as salad greens. The rhizome of Astilboides tabularis has been used to make wine and produces tannin. Several genera include highly valued ornamentals

Etymology: Saxifraga is derived from Latin saxum, a rock, and frango, to break, and two possible reasons for the name have been suggested. Some species grow in rock crevices and appear to break rocks, but alternatively it may refer to the former medicinal use of breaking up kidney stones.

Chrysosplenium davidii, private garden, Kingston upon Thames, Surrey, UK [165]

166. CRASSULACEAE Stonecrop family

These terrestrial, perennial and annual herbs, sometimes shrubs, rarely tree-like, aquatic, scandent or epiphytic, are always more or less succulent. Their stems are succulent, may form rhizomes, underground stems or corms and often have bulbils along the stem or on leaf margins. Many grow easily into new plants from vegetative parts that have fallen off the parent plant. Leaves are alternate or opposite, sessile or petiolate, without stipules, and can be placed along the stem or spirally crowded at the tips of stems, or in a basal rosette. The simple or rarely pinnately divided blades are usually entire or broadly lobed, sometimes dentate or more deeply incised and flat or round in crosssection. Inflorescences are usually terminal and most often many-flowered thyrses composed of cymes, rarely true panicles, racemes or spikes, often many branched and bracteate. The bisexual, rarely unisexual, flowers are actinomorphic or rarely zygomorphic and usually pentamerous, although variation in numbers of flower parts is great. The four to 20 sepals are

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SAXIFRAGALES

EUDICOTS

Sedum caeruleum, Sicily, Italy [166]

Graptopetalum paraguayense, National Botanic Garden of Ireland, Glasnevin [166]

Aichryson laxum, Royal Botanic Gardens, Kew, UK [166]

Kalanchoë fedtschenkoi, The Living Desert, Palm Desert, California, USA [166]

free or fused at the base and sometimes clearly unequal in size. The (3–)4–20(–32) petals are free or fused and sometimes form a tube. Stamens are as many as or twice the number of petals, the filaments free or fused with the corolla tube. Anthers are basifixed and open lengthwise. The superior (to partially inferior) ovary has as many carpels as petals, the carpels usually free or nearly so and each forming a single locule, at the base with a nectary scale. Fruits are follicles that open along the carpel suture and are usually many-seeded. Distribution: The family occurs worldwide, but is absent from some areas. It occurs in North America from the Arctic to tropical Mesoamerica and the Caribbean, in western and southeastern South America, across Eurasia south to the Himalayas and southern China, north and Sub-Saharan Africa,

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Crassula ovata, private garden, San Francisco, USA [166]

Madagascar, southern Arabia, Luzon, southern Australia and New Zealand and on Antarctic islands. There are particular areas with species radiations in the Macaronesian Islands and southern Africa. Phylogeny and evolution: Crassulaceae are estimated to have originated in East Africa between 60 and 100 million years ago, and some authors place the age more specifically around 70 million years. There is a deep split in the family between Crassuloideae and the rest. The taxonomy of Crassulaceae is complicated because morphological characters used to describe genera in the past do not seem to follow clades, and moreover species readily hybridise across genera in the wild and in cultivation, making identification contentious and classification problematic. Sedum is widely polyphyletic even when

Umbilicus rupestris, South Wales, UK [166]

segregate genera are accepted, and perhaps the best solution in the future may be to unite the entire Sempervivoideae into a single genus or at least merge all of tribe Sedeae into Sedum s.l. (including Dudleya, Echeveria, Graptopetalum, Lenophyllum, Pachyphytum, Prometheum, Rosularia, Sedella, Thompsonella and Villadia), all Telephiae in Orostachys (including Sinocrassula, Kungia, Meterostachys and Hylotelephium) and expand Aeonium and Sempervivum to include a couple of Sedum species placed there by molecular data. This may, however, cause problems in recognising these genera morphologically and thus a broad Sedum may be a better option, especially because other genera such as Orostachys and Umbilicus are also polyphyletic in the traditional sense. Regardless, a revised generic reclassification and new combinations will be needed.

SAXIFRAGALES

EUDICOTS

Genera and species: Crassulaceae include 7–35 genera (depending on the status of Sedum) and c. 1,400 species in three subfamilies: Crassuloideae – Crassula (c. 195) and Hypagophytum (1); Kalanchoideae – Andromischus (c. 26), Cotyledon (11), Kalanchoë (c. 144) and Tylecodon (46); Sempervivoideae, which are probably better united into the single genus Sedum (then with c. 979 species and to be included in Kalanchoideae), otherwise – Aeonium (c. 36), Afrovivella (1), Aichryson (14), Chiastophyllum (1), Dudleya (c. 47), Echeveria (c. 139), Graptopetalum (18), Hylotelephium (c. 27), Kungia (2), Lenophyllum (7), Meterostachys (1), Monanthes (9), Orostachys (11), Pachyphytum (15), Perrierosedum (1), Petrosedum (7), Phedimus (13), Pistorinia (3), Prometheum (8), Pseudosedum (12), Rhodiola (c. 58), Rosularia (17), Sedella (3), Sedum (c. 420), Sempervivum (c. 63), Sinocrassula (7), Thompsonella (6), Umbilicus (12) and Villadia (21). Uses: Wall pepper, Sedum acre, has a peppery taste and was used in Europe as a spice and is excellent added to salads. Trip-madame, Petrosedum rupestrum, has also been used as a salad green and pot-herb. Many species were used as a cure for burns and probably for a similar reason common houseleek, Sempervivum tectorum, was planted on roofs as a magical protection against thunder and lightning. A tincture of the roots of roseroot, Rhodiola rosea, was used in earlier times to elevate the spirits. It has proved to be medically effective in treating depression and bad moods. Many species of Crassulaceae are cultivated as garden or rockery ornamentals. The jade or money plant (Crassula ovata) and Kalanchoë blossfeldiana are especially popular pot plants around the world and are produced in large quantities. CAM photosynthesis: The family is the source of the name of a particular pathway of photosynthesis, crassulacean acid metabolism (CAM), which was first discovered in this family. CAM photosynthesis evolved independently in many clades (and all members of Crassulaceae have it) as an adaptation to arid environments. In CAM plants the leaf guard

cells remain shut during the day to reduce water loss. At night, they open to absorb carbon dioxide, which is stored as malate and used as a substrate for photosynthesis during the day. Etymology: Crassula is a diminutive form of Latin crassus, thick, referring to the fleshy leaves.

167. APHANOPETALACEAE Gum-vine family

petals and stamens to form a short floral tube (hypanthium). The four petals are minute but can be absent even in the same individual. Eight stamens have nearly basifixed anthers that open by lengthwise slits. The semiinferior ovary is composed of four laterally fused carpels into a tetralocular, four-ribbed pistil topped by a four-lobed style. The fruit is a hard nut with persistent enlarged sepals. Distribution: This family is restricted to Australia; in Queensland and New South Wales it is found in riparian scrub and in Western Australia it is found locally in limestone crevices. Phylogeny and evolution: On morphological grounds the placement of Aphanopetalum has been difficult. It was previously placed in Cunoniaceae, Iteaceae and Saxifragaceae, but does not agree with several characters of those families. Molecular evidence places this family near Crassulaceae in Saxifragales, and the clade is estimated to be c. 60 million years old.

A family of scrambling and climbing shrubs, these plants have stems with prominent lenticels. Leaves are opposite, simple and shortly petiolate. They lack stipules but have minute toothed structures around the internodes. Blades are serrate to almost entire and have pinnate venation. Inflorescences are axillary lax panicles enclosed by two prophylls. The actinomorphic flowers are bisexual and have four persistent white sepals and no or reduced petals. The base of the sepals is fused with the basal portion of

Etymology: Aphanopetalum is composed from Greek αφανώς (afanos), inconspicuous, and πετάλων (petalon), a petal.

Aphanopetalum resinosum, Mt Cordeaux, Queensland, Australia (JC) [167]

Aphanopetalum resinosum, Mt Cordeaux, Queensland, Australia (JC) [167]

Genera and species: The sole genus in this family is Aphanopetalum with two species: A. clematideum and A. resinosum.

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SAXIFRAGALES

Tetracarpaea tasmanica, Mt Field National Park, Tasmania, Australia (CD) [168]

EUDICOTS

Penthorum sedoides, private garden, Kingston upon Thames, Surrey, UK [169]

168. TETRACARPAEACEAE Delicate-laurel family

Haloragodendron glandulosum, Australian National Botanic Garden, Canberra [170]

Phylogeny and evolution: The placement of Tetracarpaeaceae has long been contentious, and this species has been suggested to belong in Cunoniaceae, Escalloniaceae and Saxifragaceae. Molecular evidence has placed it as sister to Haloragaceae and Penthoraceae. Genera and species: The only species in this family is Tetracarpaea tasmanica.

Low, bushy shrubs with upright branches make up this family. Their alternate, petiolate leaves lack stipules, and the blades are simple, crenate or serrate and have pinnate venation with secondary veins terminating near the margin. Inflorescences are terminal, erect, bracteate racemes with small, bisexual, actinomorphic flowers. The four sepals are free and persistent, the four petals are free, spreading, clawed at the base and spathulate. The four or eight stamens have free filaments and basifixed anthers. The superior ovary is composed of four (rarely five) free, stalked carpels with sessile stigmas. Fruits are follicles that open along the carpel suture exposing numerous seeds. Distribution: This family is endemic to Tasmania, where it is restricted to subalpine habitats.

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Etymology: Tetracarpaea is composed of Greek τετρα (tetra), four, and καρπός (carpos), a fruit, in reference to the four-carpellate ovaries.

169. PENTHORACEAE Ditch-stonecrop family

Glischrocaryon aureum, Mt Benia, Western Australia [170]

sharply serrate or doubly serrate margins. Terminal inflorescences are scorpioid racemes with actinomorphic, bisexual flowers that have a hypanthium to which sepals and petals are attached. The usually five (sometimes up to eight) sepals are fused, and one to eight petals are free or absent. The ten stamens are free from each other but are placed on the hypanthium rim, appearing fused to the ovary. The basifixed anthers open by lengthwise slits, and there are no nectaries at the base of the stamens. The superior or semi-inferior ovary is composed of usually five (sometimes four or up to eight) carpels that are fused basally and laterally and are partially fused to the hypanthium, and each carpel is tipped with a distinct short style and capitate stigma. The fruit is a circumscissile capsule that opens at the top, containing up to 400 seeds. Distribution: This family is distributed in eastern North America and temperate East Asia.

This family consists of perennial herbs with simple or branched stems. Cauline leaves are alternate and lack stipules. Petioles are sometimes present, and the simple blades have

Phylogeny and evolution: Placement of Penthorum has been disputed extensively in the past, as it was sometimes considered it to be transitional form between Crassulaceae and Saxifragaceae. Classification of the genus based on morphological, anatomical or embryological traits did not lead to agreement,

SAXIFRAGALES

EUDICOTS

but molecular studies indicated that the genus is sister to Haloragaceae. Even though the stem group of Penthoraceae has been dated to be c. 45 million years old, the split between the North American and East Asian species happened less than 6.5 million years ago. Genera and species: The sole genus is Penthorum with two species, P. chinense and P. sedoides. Uses: All parts of Penthorum are edible after cooking, but overconsumption may function as a laxative or respiratory sedative. Etymology: Penthorum is derived from Greek πέντε (pente), five, in reference to the five-parted fruits.

170. HALORAGACEAE Water-milfoil family

This is a family composed of small trees, shrubs and perennial and annual terrestrial and aquatic herbs. Stems are upright or creeping and rooting at the lower nodes. Stems can be condensed to form turions for overwintering in aquatic species, and sometimes filiform appendages are found in leaf axils and elsewhere along the stem. Leaves are opposite or in whorls (verticillate), without stipules and sessile or petiolate. Blades are simple or deeply pinnately dissected, the margin entire or toothed, and heterophylly occurs in the aquatic, partially submerged taxa. Inflorescences are compound thyrses, panicles or spikes, or the flowers can be solitary in the leaf axils. The bisexual or unisexual flowers are actinomorphic and dimerous. The two or four sepals are fused to the ovary (absent in female flowers of Myriophyllum), and the usually two or four, rarely eight, petals are free,

keeled or hooded (absent in female flowers of some taxa). There are two, four or eight stamens with short filaments and basifixed anthers that open by slits. The inferior ovary is composed of four carpels, and each is topped with a free style and a capitate, sometimes fimbriate stigma. The fruit is usually a one- to four-seeded nutlet or capsule that splits into two or four parts, the outside of which is often winged, ribbed or tuberculate. Distribution: The family has a nearly global distribution and occurs in North America, most of South America, Sub-Saharan Africa, Eurasia, Malesia, Australia, New Zealand and the Pacific. Phylogeny and evolution: Previously thought to be part of Myrtales, where they do not fit well morphologically, molecular analyses have now placed them in Saxifragales, sister to Penthoraceae. The earliest fossils, known from the Upper Cretaceous, are fossil fruits from Mexico and fossil pollen from Europe. Tertiary pollen is common in Europe, North America and New Zealand. Proserpinaca macro-fossils are known from Pliocene Europe and Asia where it is no longer found. Molecular results also show that Gonocarpus and Haloragis are not monophyletic in their traditional circumscription, resulting in the acceptance of Trihaloragis and Meionectes, respectively.

Cynomorium coccineum, Morocco (HR) [171]

Genera and species: This is a family of 11 genera and c. 145 species: Glischrocaryon (5), Gonocarpus (40), Haloragis (26), Haloragodendron (5), Laurembergia (4), Meionectes (3), Meziella (1), Myriophyllum (c. 60), Proserpinaca (2), Vinkia (1) and Trihaloragis (1). Uses: Some species of Myriophyllum are cultivated as aquarium or pond plants and may cause havoc when they escape and naturalise in watercourses. Etymology: Haloragis is the Latinised form of the Greek άλας (halas), salt, and ρόγες (rhoges) grapes or berries.

171. CYNOMORIACEAE Tarthuth family

These perennial, bisexual herbs are parasites on other plants and lack chlorophyll. The entire plant has a reddish-brown colour. The roots are fleshy, forming a rhizome that is attached to the host, and the stem is usually simple,

Cynomorium coccineum, with fly pollinator, Morocco (HR) [171]

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SAXIFRAGALES rarely branched. The scale-like brown leaves are arranged spirally along the stem, which is topped with a terminal spadix of flowers. The four to six (sometimes up to eight) tepals are usually fused basally, rarely free. Flowers are unisexual, and male flowers have a single stamen fused to the perianth with the ovary reduced to a nectary. Female flowers are composed of an inferior uniloculate ovary, topped by a single long, channelled style. Fruits are nutlets. Plants parasitise the roots of various hosts, mainly Amaranthaceae, Cistaceae, Nitrariaceae and Tamaricaceae. Distribution: Cynomoriaceae can be found in deserts and arid regions around the Mediterranean region, from Lanzarote in the Canary Islands and Mauritania in North Africa through to Egypt, south into

EUDICOTS

Phylogeny and evolution: Previously Cynomoriaceae were thought to belong to Balanophoraceae, another family of holoparasites, but there are several morphological differences. Molecular analyses place this family in Saxifragales, albeit without a well-supported placement among those families. Other analyses have placed them in other orders (e.g. Rosales), so the correct relationships and taxonomic placement is still a matter of debate.

Uses: Cynomorium coccineum, known in Arabic as tarthuth, or in English as Maltese mushroom, grows in the desert after rains and has been harvested for thousands of years for food and medicine and as a dye for fabric. Bedouins clean the freshly picked spikes, peel off the outer skin and eat the flavourful white interior, which is sweet tasting. It is edible raw, with a pleasant crisp, succulent texture. In the ‘doctrine of signatures’, it was believed that the phallic shape of the inflorescences would mean that it is a cure for erectile dysfunction and other sexual health issues. It has been used for these purposes throughout its range, probably to no avail.

Genera and species: The sole genus is Cynomorium with two species: C. coccineum and C. songaricum.

Etymology: Cynomorium is composed of classical Greek κυνός (kynos), a dog, and μοριων (morion), a penis.

the Arabian Peninsula to Oman and north to Malta, Greece and Iraq, and in Central Asia to Mongolia and north-central China.

VITALES Relationships of this order have long been uncertain, but it is now known that they are sister to all rosids. They include a single family.

172. VITACEAE Grapevine family

Vitaceae are a family of bisexual and unisexual woody climbers, vines, shrubs and small trees. Stems often have lenticels, and the bark may be shedding, with branches often swollen at the nodes, usually unarmed or with rows of prickles. Tendrils are present or not, but can be simple, forked or multiplebranched, sometimes with adhesive discs

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at the tips of each branch (Parthenocissus), usually placed opposite the leaves. Stipules are present, normally two and interpetiolar or sheathing the petiole margins with stipular wings (Leea). Leaves are petiolate, simple, lobed or palmately compound, trifoliate or one to three times pinnate, alternate, but usually opposite tendrils or inflorescences, often with structures called ‘pearl glands’ on the leaf margins or blade surfaces. Inflorescences are panicles, corymbs or rarely spikes, usually composed of cymes, usually leaf-opposed, or axillary (Cayratia, Tetrastigma). The actinomorphic, unisexual or bisexual flowers have a fused often cupulate calyx with four or five (or up to seven) teeth or lobes, glandtipped in Leea. The four, five or up to seven (Rhoicissus) petals are free or basally fused or sometimes fused to form a calyptrum (Vitis). Stamens are as many as and placed opposite

the petals, and anthers are nearly basifixed and open by lengthwise slits. The floral nectary disc is placed inside the stamens and is ring-shaped, cupular, tubular or glandular. The superior ovary is composed of two or three fused carpels making two or four to six locules, which are usually topped with a short or elongate style and a capitate, discoid or four-lobed stigma. The fruit is a one- to four-seeded, juicy or dryish berry. Distribution: Vitaceae are distributed across the warm temperate and tropical regions of the world. They are found in North America north to the Great Lakes and New England south through Central and South America to Tierra del Fuego. They occur from the Sahel region to southern Africa, in Madagascar, Yemen, Italy and southeastern Europe, the Caucasus, northern Iran to Central Asia, India, Southeast

VITALES

EUDICOTS

Leea coccinea, Brooklyn Botanic Garden, New York, USA [172]

Parthenocissus vitacea, New Mexico, USA (DZ)

Clematicissus angustissima, Western Australia [172]

Vitis vinifera, Transylvania, Romania [172]

and East Asia, north to Sachalin and the Russian Far East, and south to Australia and northern New Zealand.

Eocene and Oligocene from the Neotropics, where the genus is now absent.

Vitis species, such as bush grape (V. acerifolia), canyon grape (V. arizonica), skunk grape (V. labrusca), mountain grape (V. monticola), cat grape (V. palmata), river grape (V. riparia), muscadine (V. rotundifolia), sand grape (V. rupestris), frost grape (V. vulpina) etc., many of which are locally eaten or made into local wines, liqueurs or jellies. Several wild species have been used for hybridising with common grapes, for different flavours, vigour, climatic and disease tolerance. Cream of tartar (potassium hydrogen tartrate) crystallises out of wine on the sides of barrels and bottles. It is a component of most baking powder. Leaves of some Cissus species are edible, and C. gongylodes is commonly cultivated and harvested by local tribes in South America. Cayratia geniculata is used to make ropes. Some species are cultivated as ornamentals, such as Ampelopsis, Cissus, Leea, Parthenocissus, Rhoicissus and Vitis coignetiae. Tetrastigma is the host plant for the endoparasitic Rafflesia (Rafflesiaceae), the genus with the largest flowers.

[172]

Phylogeny and evolution: Vitaceae are the sole family in Vitales, an order often positioned as sister to all other rosids. Relationships of Vitaceae have long been considered uncertain, and the family was often associated with Rhamnaceae or even Proteaceae because all have stamens opposite the petals. Leeaceae have in all analyses been found to be sister to Vitaceae s.s. and because the two share numerous characters they are now merged. Generic delimitation in Vitaceae will need some attention by future taxonomists because Cissus appears to be polyphyletic and Tetrastigma is embedded in Cayratia. Pterisanthes has nomenclatural priority over Ampelocissus, but combinations have not been made. Late Cretaceous fossil leaves have been assigned to Vitaceae. The distinctive seeds of Vitaceae are found frequently in Tertiary deposits in North America and Europe. Ampelocissus fossils are known from Mesoamerican and Peruvian Oligocene sediments (c. 30–28 million years old). Leea fossils are known from the Late

Genera and species: Vitaceae include 14 genera and about 910 species in two subfamilies; Leeoideae – Leea (34); Vitoideae – Acareosperma (1), Ampelocissus (c. 100), Ampelopsis (25), Cayratia (c. 65), Cissus (c. 350), Clematicissus (1), Cyphostemma (c. 150), Nothocissus (4), Parthenocissus (10), Pterocissus (1), Rhoicissus (10), Tetrastigma (c. 95) and Vitis (c. 65). Uses: Grapes (Vitis vinifera) can be eaten fresh or dried (raisins, currants), made into jellies or fermented into wine. The leaves are also edible, often stuffed with meat, rice and vegetables. Traditionally a Mediterranean crop, grapes have been widely cultivated, especially in France, Spain, Germany, Austrlia, Greece, Crimea, California, Chile, South Africa, Australia, New Zealand and China, and recent vineyards can be found as far north as Michigan, England and Sweden, this hardiness probably due to hybridisation of French varieties with Vitis riparia. Many other species produce edible fruits, especially Ampelocissus, Cayratia, Tetrastigma harmandii and other

Etymology: Vitis is Latin for a grape vine. It is derived from Proto-Indo-European weytis, referring to something that twines, winds, bends or turns.

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ZYGOPHYLLALES

EUDICOTS

ZYGOPHYLLALES Families 173 and 174 form the order Zygophyllales, a relatively isolated order of two closely related families. The lineage may have evolved c. 108 million years ago, whereas the families diverged somewhere between 70 and 64 million years ago. Zygophyllales are sister to the rest of the rosid I (fabid) clade.

173. KRAMERIACEAE Ratany family

This is a family of parasitic shrubs and perennial herbs with rhizomes and haustorial roots that parasitise a variety of other flowering plants. They have green, alternate, spirally arranged leaves without stipules. Leaf blades can be sessile or petiolate and simple or trifoliate with an entire margin and reticulate venation. Inflorescences are terminal racemes, panicles or axillary single flowers. The bisexual zygomorphic flowers have (four or) five free, showy, colourful sepals. There are (four or) five petals of which two are reduced to glandular structures secreting oil, and the other three variously clawed or lanceolate, clustered on one side of the ovary. The four (rarely three) stamens

have stout filaments that are fused at the base. Anthers are tetralocular, tubular and the same diameter as the filaments and open by membranous pores. The superior ovary is composed of two carpels, of which one is suppressed to form a single locule topped by a style and small stigma. Fruits are globose or slightly flattened, indehiscent, spiny capsules with a single globose seed. Distribution: This family can be found in North America, from the southwestern North America to Florida, through Mesoamerica, the Lesser Antilles and dry regions in South America. Phylogeny and evolution: The highly specialised genus Krameria is the only member of the family. Its affinities have historically been uncertain, and it has been placed variously in Fabaceae and Polygalaceae; more recently it has been accorded familial status, and it was demonstrated that it is the sister to Zygophyllaceae, with which it shares few obvious synapomorphies. Krameriaceae grow in the same habitats as many Zygophyllaceae and have the ability to withstand similarly dry conditions. However, they are unlike

Krameria bicolor, fruit, Andreas Canyon, Palm Springs, California, USA [173]

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Zygophyllaceae in many other respects, notably in having extremely zygomorphic flowers and being root parasites, including some that parasitise species of Larrea (Zygophyllaceae). All species are pollinated by only female oil-collecting solitary bees of the genus Centris (Apidae). Genera and species: The sole genus in this family is Krameria with 18 species. Uses: Due to its astringent properties, ratany (Krameria triandra) has minor economic importance as a medicinal plant, especially for enteritis and angina, but treatment has been proven to be ineffective. It is most commonly used in dental products such as mouthwash and herbal toothpaste, helping to heal gum irritations and minor infection. It is occasionally used as a dye and as an ingredient in cosmetics. Etymology: Krameria is named for Wilhelm Heinrich Kramer (died 1765), a German naturalist and physician, who described the plants and animals of Lower Austria in 1756, which was one of the first works to apply the Linnaean binomial system.

Krameria bicolor, Andreas Canyon, Palm Springs, California, USA [173]

ZYGOPHYLLALES

EUDICOTS

174. ZYGOPHYLLACEAE Twinleaf family

This family of trees, shrubs, perennial and annual herbs often have jointed branches with swollen nodes that are sometimes armed with axillary or stipular thorns. Opposite, rarely alternate, leaves have stipules that are free or fused across the node. Blades are usually bifoliate, trifoliate or pinnate, rarely simple, and leaflets are usually asymmetrical and have an entire margin, usually flat, sometimes terete, often fleshy. Inflorescences are few-flowered cymes that are usually reduced to solitary or paired flowers. The bisexual, actinomorphic to zygomorphic flowers have four to six free or basally fused sepals. The four to six (rarely absent) petals are free and are often clawed. A nectary disc is often present between petals and stamens. Stamens are as many as or twice as many as petals. Filaments sometimes have scales or appendages at their base, anthers are tetralocular, dorsifixed and dehiscent via a Kallstroemia grandiflora, New Mexico, USA (DZ) [174]

Zygophyllum fabago, Ani, Turkey [174]

lengthwise slit. The superior ovary is usually tetra- to pentalocular, or sometimes has fewer (two or three) or up to 12 locules. The style is apical or gynobasic (Zygophyllum), filiform or subulate, and stigmas are capitate, clavate or somewhat lobed or ridged. Fruits are capsules, splitting into mericarps that may be winged, lobed, angled, spined, tuberculate or, in Balanites, a drupe. Distribution: Zygophyllaceae can be found in dry and warm-temperate, tropical to temperate areas of the Americas (Minnesota to Patagonia), Mediterranean Europe, Africa, Madagascar, western, southern, central and eastern Asia, Malesia and Australia, mostly in arid or saline habitats. Phylogeny and evolution: Nitraria, Peganum and Tetradiclis were originally included in Zygophyllaceae, but molecular studies have revealed the relationships of these genera to be among other eurosid families. They are now placed in their own family Nitrariaceae (Sapindales). Balanites has a distinctive morphology with alternate leaves and a calyx that envelops the flower when young. It was previously placed in its own family, but molecular evidence places it close to Zygophyllum. Five subfamilies are sometimes recognised: Larreoideae, Morkilioideae, Seetzenioideae, Tribuloideae and Zygophylloideae. Larrea tridentata, Andreas Canyon, Palm Springs, California, USA [174]

Genera and species: This is a family of 22 genera and c. 220 species: Augea (1), Balanites (9), Bulnesia (8), Fagonia (c. 30), Guaiacum (6), Kallstroemia (17), Kelleronia (3), Larrea (6), Metharme (1), Morkillia (2), Neoluederitzia (1), Pintoa (1), Plectrocarpa (3), Porlieria (6), Seetzenia (1), Sericodes (1), Sisyndite (1), Tetraena (40), Tribulopsis (5), Tribulus (c. 25), Viscainoa (1) and Zygophyllum (c. 50). Uses: Lignum vitae (Guaiacum) is the hardest wood of all. Resin from Guaiacum sanctum has been used medicinally, especially in the 16th century to treat syphilis, and its populations were nearly exterminated for that purpose. This species is now listed in the CITES appendices. It is currently used as an antioxidant food additive (E314). Oil of guaiac is derived from Bulnesia sarmientoi, which is a fragrance used in soap. Retamo wax, harvested from B. retama, is used in cosmetics and polishing. Balanites fruits have high nutritional value (called ‘desert dates’), and their oil is also made into soap. Zygophyllum and Larrea flower buds have been used as caper substitutes. Etymology: Zygophyllum is derived from the Greek ζυγόν (zygon), yoke, and φύλλων ( fyllon), leaf, in reference to each leaf having two leaflets. Balanites aegyptiaca, Kenya [174]

Zygophyllum fruticulosum, Western Australia [174]

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FABALES Families 175 to 178 comprise the order Fabales, which includes nearly ten percent of eudicot diversity. The bulk of this is made up of Fabaceae, a dominant family in many ecosystems around the world. The order is well supported, although relationships among the families in the order are still disputed. The crown group is dated between 87 and 72 million years old.

175. QUILLAJACEAE Soapbark-tree family

These evergreen trees have saponaceous bark. Alternate, simple leaves are leathery and petiolate. Stipules are small and fall off early, and leaf blades are entire with pinnate venation. Inf lorescences are terminal or axillary clusters of a few flowers, the terminal ones bisexual, the lateral ones male; pedicels have prophylls. The five sepals are free and valvate, and the five petals are spathulate and white or cream. The nectary disc is thick and showy; it lines the receptacle and has five lobes fused to the sepals. The ten stamens

are in two whorls, one inserted near the tips of the disc lobes on the sepals, the other around the base of the ovary. Filaments are subulate, and the anthers have two thecae that open by lengthwise slits. The superior ovary is composed of five carpels that are basally fused, each with a terminal stylodium. Fruits are star-shaped follicles that open on the upper side, each carpel into two lobes exposing longwinged seeds. Distribution: This family is almost entirely restricted to the northern Andes in Chile with a disjunct population in northern Argentina, Uruguay and southeastern Brazil. Phylogeny and evolution: Despite uncertain relationships among families in Fabales, Quillajaceae are generally found to be sister to the rest. Until recently Quillaja was included in Rosaceae without question because it shares many characters with certain genera in that family (e.g. Kageneckia). Apart from molecular evidence showing that it is not

Quillaja saponaria, University of Talca Botanical Garden, Chile (CD) [175]

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related to Rosaceae, it has a base chromosome number of 14 and scalariform perforation plates, which do not occur in Rosaceae. Genera and species: The sole genus in the family, Quillaja, includes three species. Uses: The inner bark of the soapbark tree (Quillaja saponaria) contains saponins, which can be used as soap. The Andean peoples used it also for treatment of various chest infections, the saponin helping to produce more mucus in the airways and eliciting coughing, thus removing phlegm. It is also used as a humectant in various processed foods and foaming agent in fizzy drinks, whipping cream and fire extinguishers. It can also be used for the preparation of veterinary vaccines. Etymology: Quillaja is a Latinised form of the Araucani name for the plant, quillai (or killai). The scientific name is thus to be pronounced as ‘killaya’ in both English and Spanish.

Quillaja saponaria, fruit, San Francisco Botanical Garden, USA [175]

FABALES

EUDICOTS

are actinomorphic or slightly or completely zygomorphic. They usually have five (sometimes three or six) sepals that are free or fused into a tube, sometimes bilabiate, rarely reduced or vestigial. Petals are generally as many as the sepals (usually five), seldom fewer or none, and are distinct and often (Faboideae) highly differentiated into a papilionaceous corolla: an outermost upper petal (standard); innermost in Cercis and related to former Caesalpinoideae, two lateral petals that are more or less parallel to each other (wings) and the lower two innermost petals usually fused by their lower margins and forming a keel. Stamens are mostly ten, sometimes fewer or more numerous (especially in Mimosoideae), free or often fused by their filaments to form a closed or open sheath. The bilocular anthers open lengthwise or by pores and are uniform or dimorphic and then alternately basifixed and dorsifixed. The superior ovary is nearly always composed of a solitary carpel (rarely two or more free carpels), and it is unilocular or chambered (septate). The fruit is a pod (legume) that opens by one or both sutures, sometimes indehiscent or jointed and breaking up into single-seeded segments, sometimes winged.

176. FABACEAE Pea family

This large family consists of trees, shrubs, vines and perennial and annual herbs. Stems can be self-supporting and erect, with or without spines, and climbing species can be twining or have tips of branches forming tendrils (Bauhinia). Roots often bear nodules that harbour nitrogen-fixing bacteria. Their leaves are usually alternate, rarely opposite or whorled, and stipules are usually present, sometimes developed into spines or absent. Leaves are usually pinnate or bipinnate, sometimes palmately compound or trifoliolate, seldom unifoliolate or simple, and in some cases they are modified into narrow phyllodes or the terminal leaflets are converted into tendrils; petioles are usually present. Inflorescences are usually racemes, corymbs, spikes, heads or panicles, rarely flowers solitary or clustered in the leaf axils. The bisexual or rarely unisexual flowers

Distribution: This is a more or less globally distributed family, with woody genera more prominent in the tropics, subtropics and

Terminology of papilionaceous flower. Caragana pygmaea [176]

pedicel

Southern Hemisphere, and herbaceous genera more diverse in temperate regions, especially in mild winter-rain and dry-summer climates. Phylogeny and evolution: The crown group of Fabaceae is c. 75 million years old. This is a species-rich group, and diversification may in some clades be related to genome duplication early-on in the evolution of these lineages. This genome duplication is also thought to be related to the evolution of N-fixing bacterial nodules in their roots. Biogeography of the family involves a combination of vicariance and long-distance dispersal. Genera such as Hymenaea (resin of which made amber deposits) probably crossed the Atlantic during the Tertiary, and most other bicontinental genera have divergence times that are too young to be explained by continental drift. The classic division into the three traditional subfamilies (or families) does not hold up, due to the polyphyly of Caesalpinioideae. A recent classification of the family now recognises six subfamilies: Duparquetioideae, Cercidoideae, Detarioideae, Dialioideae, Faboideae and Caesalpinioideae. Not all species have been sequenced and further progress is still to be made. Faboideae are frequently herbs or vines and often have once compound leaves and

Vachellia drepanolobium, Kenya [176]

calyx

standard

wings

stamens style keel

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249

FABALES usually zygomorphic, usually papilionaceous flowers (as described above), although there are also genera that are trees with regular flowers included in this subfamily. Stamens are usually fused, and fruits are often explosively dehiscent, with the two valves twisting. This clade is estimated to have diversified c. 30 million years ago. Mimosoids (fomerly subfamily Mimosoideae, now part of Caesalpinioideae), are mostly woody plants with usually bipinnate leaves and nectaries on their petioles. They have actinomorphic flowers that have long, coloured filaments, and sepals and petals are fused. Seeds have a u-shaped line on both sides. Early divergence of this group occurred in Africa some 21 million years ago, but older ages have been suggested due to recent fossil finds.

Genera and species: This is a large family consisting of about 745 genera and c. 16,020 species, with over a quarter of all species in five genera (Acacia, Astragalus, Crotalaria, Indigofera and Mimosa). A formal classification has recently been published, with the following six subfamilies mentioned above: Duparquetioideae (1 genus) – Duparquetia (1); Cercidoideae (13 genera;

313 species) – Adenolobus (2), Barklya (1), Bauhinia (c. 125), Brenierea (1), Cercis (10), Gigasiphon (5), Griffonia (4), Lasiobema (c. 17), Lysiphyllum (c. 9), Phanera (c. 85), Piliostigma (c. 4), Schnella (45) and Tylosema (5); Detarioideae (84 genera, 755 species) – Afzelia (11), Amherstia (1), Annea (2), Anthonotha (c. 30), Aphanocalyx (14), Augouardia (1), Baik iaea (c. 6), Barnebydendron (1), Berlinia (21), Bikinia (10), Brachycylix (1), Brachystegia (26), Brandzeia (1), Brodriguesia (1), Brownea (12), Browneopsis (6), Colophospermum (1), Copaifera (c. 35), Crudia (c. 53), Cryptosepalum (c. 11), Cynometra (c. 85), Daniellia (c. 9), Detarium (3), Dicymbe (c. 18), Didelotia (c. 11), Ecuadendron (1), Elizabetha (c. 11), Endertia (1), Englerodendron (1), Eperua (14), Eurypetalum (3), Gabonius (1),

Paubrasilia echinata, Recife, Pernambuco, Brazil [176]

Delonix regia, Réunion [176]

Parkinsonia aculeata, Isabela, Galápagos Islands [176]

Dichrostachys cinerea, cultivated in Guadeloupe [176]

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EUDICOTS

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The rest (previously called “Caesalpinioideae”) are woody plants that have slightly zygomorphic f lowers (to more strongly zygomorphic and papilionaceous when Cercis and relatives are included). These often have a well-developed hypanthium, but do not form a natural unit. A number of genera await revision, and generic delimitations of some are not clear.

Mimosa pudica, Guadeloupe [176]

FABALES

EUDICOTS

Acacia spectabilis, Durran Durra, New South Wales, Australia [176]

Cercis siliquastrum, Lebanon [176]

Gilbertiodendron (c. 27), Gilletiodendron (5), Goniorrhachis (1), Gossweilerodendron (2), Guibourtia (c. 14), Hardwickia (1), Heterostemon (7), Humboldtia (6), Hylodendron (1), Hymenaea (14), Hymenostegia (c. 15), Icuria (1), Intsia (3), Isoberlinia (5), Julbernardia (c. 11), Kingiodendron (6), Lebruniodendron (1), Leonardoxa (1), Leucostegane (2), Librevillea (1), Loesenera (4), Lysidice (2), Macrolobium (c. 75), Maniltoa (c. 23), Michelsonia (1), Micklethwaitia (1), Microberlinia (2), Neoapaloxylon (3), Neochevalierodendron (1), Normandiodendron (2), Oddoniodendron (3), Oxystigma (5), Paloue (4), Paloveopsis (1), Paramacrolobium (1), Pellegrinodendron (1), Peltogyne (c. 25), Plagiosiphon (5), Polystemonanthus (1), Prioria (1), Pseudomacrolobium (1), Saraca (11), Schotia (4), Scorodophloeus (3), Sindora (c. 19), Sindoropsis (1), Stemonocoleus (1), Talbotiella (3), Tamarindus (1), Tessmannia (c. 12), Tetraberlinia (7) and Zenkerella (5); Dialioideae (20 genera, 714 species) – Androcalymma (1), Apuleia (3), Baudouinia (6), Cassia (c. 30), Chamaecrista (c. 330), Dialium (c. 28), Dicorynia (2), Distemonanthus (1), Eligmocarpus (1), Kalappia (1), Koompassia (3), Labichea (14), Martiodendron (4), Mendoravia (1), Petalostylis (2), Poeppigia (1), Senna (c. 300), Storckelia (4), Uittienia (1) and Zenia (1); Faboideae (484 genera, 13,483 species) – Abrus (c. 17), Acmispon (8), Acosmium (1), Adenocarpus (15),

Adenodolichos (c. 17), Adesmia (c. 240), Aenictophyton (1), Aeschynomene (c. 177), Afgekia (3), Aganope (7), Airyantha (2), Akschindlium (1), Aldina (c. 14), Alexa (9), Alhagi (3), Alistilus (3), Almaleea (5), Alysicarpus (c. 27), Amburana (3), Amicia (c. 7), Ammodendron (4), Ammopiptanthus (1), Ammothamnus (2), Amorpha (c. 15), Amphicarpaea (5), Amphimas (4), Amphithalea (42), Anagyris (2), Anarthrophyllum (15), Andira (29), Angylocalyx (7), Antheroporum (4), Anthyllis (22), Antopetitia (1), Aotus (c. 17), Aphyllodium (7), Apios (c. 7), Apoplanesia (1), Apurimacia (2), Arachis (69), Argyrocytisus (1), Argyrolobium (c. 80), Arthroclianthus (c. 30), Aspalathus (278), Astragalus (c. 2,400), Ateleia (20), Austrodolichos (1), Austrosteenisia (4), Baphia (47), Baphiastrum (1), Baphiopsis (1), Baptisia (c. 16), Barbieria (1), Barnebyella (1), Behaimia (1), Bergeronia (1), Biserrula (1), Bituminaria (2), Bobgunnia (2), Bocoa (3), Bolusafra (1), Bolusanthus (1), Bolusia (5), Bossiaea (c. 60), Bowdichia (2), Bowringia (4), Brongniartia (c. 63), Brya (4), Bryaspis (2), Burkilliodendron (1), Butea (2), Cadia (7), Cajanus (34), Calia (4), Calicotome (3), Callerya (c. 20), Callistachys (1), Calobota (16), Calophaca (c. 7), Calopogonium (5), Calpurnia (7), Camoensia (2), Camptosema (10), Campylotropis (c. 37), Canavalia (c. 60), Candolleodendron (1), Caragana (c. 75), Carmichaelia (23), Carrissoa (1), Cascaronia (1), Castanospermum (1), Centrolobium (7),

Bauhinia tomentosa, Kenya [176]

Centrosema (c. 36), Chadsia (9), Chaetocalyx (13), Chapmannia (7), Chesneya (c. 30), Chorizema (27), Christia (c. 10), Chrysoscias (4), Cicer (43), Cladrastis (7), Clathrotropis (6), Cleobulia (4), Clianthus (2), Clitoria (c. 62), Clitoriopsis (1), Cochlianthus (2), Codariocalyx (2), Collaea (7), Cologania (c. 12), Colutea (c. 28), Cordyla (c. 7), Corethrodendron (4), Coronilla (9), Coursetia (c. 35), Craibia (10), Cranocarpus (3), Craspedolobium (1), Cratylia (c. 7), Cristonia (1), Crotalaria (c. 690), Cruddasia (2), Cullen (c. 34), Cyamopsis (4), Cyathostegia (1), Cyclocarpa (1), Cyclolobium (1), Cyclopia (23), Cymbosema (1), Cytisophyllum (1), Cytisopsis (2), Cytisus (c. 65), Dahlstedtia (2), Dalbergia (c. 250), Dalbergiella (3), Dalea (c. 165), Dalhousiea (3), Daviesia (135), Decorsea (6), Deguelia (c. 17), Dendrolobium (18), Derris (c. 57), Desmodiastrum (4), Desmodium (c. 275), Dewevrea (1), Dichilus (5), Dicraeopetalum (3), Dillwynia (c. 40), Dioclea (c. 40), Diphyllarium (1), Diphysa (15), Diplotropis (12), Dipogon (1), Dipteryx (c. 12), Discolobium (8), Disynstemon (1), Dolichopsis (1), Dolichos (c. 60), Dorycnium (8), Dorycnopsis (2), Droogmansia (5), Dumasia (c. 10), Dunbaria (20), Dussia (9), Dysolobium (4), Ebenus (c. 20), Echinospartum (5), Eleiotis (2), Eminia (4), Endosamara (2), Eremosparton (3), Erichsenia (1), Erinacea (1), Eriosema (c. 150), Erophaca (1), Errazurizia (4), Erythrina (c. 120), Etaballia (1), Euchilopsis (1), Euchresta (4), Eutaxia Plants of the World

251

FABALES

Swainsona formosana, South Australia [176]

(10), Eversmannia (4), Eysenhardtia (c. 14), Exostyles (4), Fiebrigiella (1), Fissicalyx (1), Flemingia (c. 33), Fordia (18), Galactia (c. 57), Galega (6), Gastrolobium (109), Geissaspis (2), Genista (c. 90), Genistidium (1), Geoffroea (2), Gliricidia (5), Glycine (19), Glycyrrhiza (c. 20), Gompholobium (44), Gonocytisus (3), Goodia (2), Grazielodendron (1), Gueldenstaedtia (c. 10), Guianodendron (1), Halimodendron (1), Hammatolobium (2), Hanslia (2), Haplormosia (1), Hardenbergia (3), Harleyodendron (1), Harpalyce (24), Hebestigma (1), Hedysarum (c. 160), Hegnera (1), Herpyza (1), Hesperolaburnum (1), Hesperothamnus (5), Hippocrepis (c. 34), Hoita (3), Holocalyx (1), Hosackia (11), Hovea (37), Humularia (c. 35), Hylodesmum (14), Hymenocarpos (1), Hymenolobium (c. 17), Hypocalyptus (3), Indigastrum (c. 8), Indigofera (c. 700), Inocarpus (3), Isotropis (10), Jacksonia (74), Kebirita (1), Kennedia (c. 15), Kotschya (31), Kummerowia (2), Kunstleria (8), Lablab (1), Laburnum (2), Lackeya (1), Ladeania (2), Lamprolobium (2), Lathyrus (c. 160), Latrobea (6), Lebeckia (15), Lecointea (4), Lembotropis (2), Lennea (3), Lens (5), Leptoderris (c. 20), Leptodesmia (3), Leptolobium (10), Leptosema (13), Lespedeza (c. 35), Lessertia (c. 50), Leucomphalos (1), Limadendron (2), Liparia (20), Lonchocarpus (c. 120), Lotononis (c. 150), Lotus (c. 125), Luetzelburgia (8), Lupinus (c. 225), Luzonia (1), Maackia (c. 8), Machaerium (c. 130), Macropsychanthus (2), Macroptilium (c. 17), 252

Christenhusz, Fay & Chase

EUDICOTS

Cadia purpurea, a legume with regular flowers, Nairobi, Kenya [176]

Macrot yloma (24), Maraniona (1), Margaritolobium (1), Marina (38), Mastersia (2), Mecopus (1), Medicago (83), Meizotropis (2), Melilotus (c. 20), Melliniella (1), Melolobium (15), Microcharis (36), Mildbraediodendron (1), Milletia (c. 150), Mirbelia (32), Monarthrocarpus (1), Monopteryx (4), Montigena (1), Mucuna (c. 105), Muellera (2), Muelleranthus (3), Mundulea (12), Myrocar p u s (5), Myrospermum (3), Myroxylon (2), Mysanthus (1), Neocollettia (1), Neoharmsia (2), Neonotonia (2), Neorautanenia (3), Neorudolphia (1), Nephrodesmus (6), Nesphostylis (4), Nissolia (13), Nogra (3), Oberholzeria (1), Ohwia (2), Olneya (1), Onobrychis (c. 130), Ononis (c. 75), Ophiocarpus (1), Ophrestia (c. 16), Orbexilum (8), Oreophysa (1), Ormocarpopsis (6), Ormocarpum (c. 18), Ormosia (c. 130), Ornithopus (5), Oryxis (1), Ostryocarpus (2), Otholobium (61), Otion (c. 8), Otoptera (2), Ottleya (13), Ougeinia (1), Oxylobium (6), Oxyrhynchus (4), Oxytropis (c. 350), Pachyrhizus (5), Panurea (2), Paracalyx (6), Paraderris (13), Paramachaerium (5), Paratephrosia (1), Parochetus (2), Parryella (1), Pearsonia (13), Pediomelum (22), Peltiera (2), Periandra (6), Pericopsis (4), Petaladenium (1), Peteria (4), Petteria (1), Phaseolus (c. 63), Philenoptera (12), Phylacium (2), Phyllodium (8), Phyllota (11), Phylloxylon (7), Physostigma (4), Pickeringia (1), Pictetia (8), Piptanthus (2), Piscidia (c. 7),

Pisum (c. 3), Plagiocarpus (1), Platycelyphium (1), Platycyamus (2), Platylobium (4), Platymiscium (19), Platypodium (2), Platysepalum (8), Podalyria (19), Podocytisus (1), Podolobium (6), Podolotus (1), Poecilanthe (c. 11), Poiretia (11), Poissonia (5), Poitea (12), Polhillia (7), Pongamiopsis (3), Pseudarthria (4), Pseudeminia (4), Pseudoeriosema (4), Pseudolotus (1), Pseudovigna (2), Psophocarpus (c. 10), Psoralea (c. 50), Psoralidium (3), Psorothamnus (9), Pterocarpus (c. 37), Pterodon (3), Ptycholobium (3), Ptychosema (2), Pueraria (c. 18), Pultenaea (104), Pycnospora (1), Pyranthus (6), Rafnia (19), Ramirezella (7), Ramorinoa (1), Requienia (3), Retama (4), Rhodopis (2), Rhynchosia (c. 230), Rhynchotropis (2), Riedeliella (3), Robinia (4), Robynsiophyton (1), Rothia (2), Rupertia (3), Sakoanala (2), Salweenia (1), Sarcodum (3), Sartoria (1), Schefflerodendron (4), Scorpiurus (2), Securigera (13), Sellocharis (1), Sesbania (c. 60), Shuteria (5), Sinodolichos (2), Smirnowia (1), Smithia (c. 20), Soemmeringia (1), Sophora (c. 50), Spartidium (1), Spartium (1), Spathionema (1), Spatholobus (29), Sphaerolobium (22), Sphaerophysa (2), Sphenostylis (7), Sphinctospermum (1), Spirotropis (3), Spongiocarpella (c. 7), Staminodianthus (3), Stauracanthus (3), Stirtonanthus (3), Stonesiella (1), Streblorrhiza (1, possibly extinct), Strongylodon (12), Strophostyles (3), Stylosanthes (c. 25), Styphnolobium (9), Sulla (7), Sutherlandia (5),

FABALES

EUDICOTS

Swainsona (84), Swartzia (c. 180), Sweetia (1), Sylvichadsia (4), Syrmatium (14), Tadehagi (c. 6), Taralea (c. 7), Taverniera (15), Templetonia (10), Tephrosia (c. 350), Teramnus (9), Tetragonolobus (6), Teyleria (3), Thermopsis (c. 23), Thinicola (1), Tibetia (4), Tipuana (1), Trifidacanthus (1), Trifolium (c. 250), Trigonella (c. 55), Tripodion (1), Trischidium (5), Uleanthus (1), Ulex (c. 15), Uraria (c. 20), Uribea (1), Urodon (4), Vandasina (1), Vatairea (8), Vataireopsis (4), Vatovaea (1), Vaughania (11), Vavilovia (1), Vicia (c. 160), Vigna (c. 104), Viminaria (1), Virgilia (2), Wajira (5), Weberbauerella (2), Wiborgia (9), Wiborgiella (9), Wisteria (6), Xanthocercis (3), Xeroderris (1), Xiphotheca (9), Zollernia (10), Zornia (c. 75) and Zygocarpum (6); Caesalpinioideae (139 genera, c. 3,725 species) – Arapatiella (2), Acrocarpus (1), Aroa (1), Balsamocarpon (1), Batesia (1), Burkea (1), Bussea (7), Caesalpinia (c. 25), Campsiandra (19), Cenostigma (3), Ceratonia (2), Chidlowia (1), Colvillea (1), Conzattia (1), Cordeauxia (1), Coulteria (10), Delonix (11), Dimorphandra (26), Diptychandra (1), Erythrophleum (10), Erythrostemon (12), Gleditsia (c. 14), Guilandina (c. 7), Gymnocladus (6), Haematoxylum (3), Hoffmannseggia (24), Jacqueshuberia (7), Lemuropisum (1), Libidibia (7), Lophocarpinia (1), Melanoxylon (1), Mezoneuron (c. 26), Moldenhawera (9), Clitoria ternatea, Royal Botanic Gardens, Kew, UK [176]

Mora (6), Moullava (1), Orphanodendron (2), Pachyelasma (1), Parkinsonia (12), Paubrasilia (1), Peltophorum (c. 6), Poincianella (c. 35), Pomaria (16), Pterogyne (1), Pterolobium (11), Recordoxylon (3), Schizolobium (1), Stachyothyrsus (2), Stahlia (1), Stenodrepanum (1), Stuhlmannia (1), Sympetalandra (5), Tachigali (c. 65), Tetrapterocarpon (2), Tara (3), Umtiza (1), Vouacapoua (3) and Zuccagnia (1); mimosoid clade (now a subclade under Caesalpinioideae) (82 genera, 3,301 species) – Abarema (46), Acacia (c. 1,075), Acaciella (15), Adenanthera (13), Adenopodia (c. 7), Alantsilodendron (10), Albizia (c. 130), Amblygonocarpus (1), Anadenanthera (2), Archidendron (94), Archidendropsis (14), Aubrevillea (2), Blanchetiodendron (1), Calliandra (c. 135), Calliandropsis (1), Calpocalyx (11), Cathormion (1), Cedrelinga (1), Chloroleucon (10), Cojoba (12), Cylicodiscus (1), Desmanthus (c. 24), Dichrostachys (14), Dinizia (1), Ebenopsis (3), Elephantorrhiza (9), Entada (c. 28), Enterolobium (11), Faidherbia (1), Falcataria (3), Fillaeopsis (1), Gagnebina (8), Guinetia (1), Havardia (5), Hesperalbizia (1), Hydrochorea (3), Indopiptadenia (1), Inga (c. 300), Kanaloa (1), Lemurodendron (1), Leucaena (22), L e u c o chloron (5), Lysilo m a (9), Macrosamanea (11), Marmaroxylon (c. 11), Microlobius (1), Mimosa (c. 500), Trifolium pratense, Turku, Finland [176]

Mimozyganthus (1), Neptunia (12), Newtonia (15), Painteria (3), Parachidendron (1), Parapiptadenia (6), Paraserianthes (1), Parkia (c. 34), Pentaclethra (3), Piptadenia (c. 21), Piptadeniastrum (1), Piptadeniopsis (1), Pithecellobium (18), Pityrocarpa (3), Plathymenia (1), Prosopidastrum (c. 5), Prosopis (c. 44), Pseudopiptadenia (11), Pseudoprosopis (7), Pseudosamanea (2), Samanea (3), Sanjappa (1), Schleinitzia (4), Senegalia (c. 230), Serianthes (c. 18), Sphinga (3), Stryphnodendron (c. 30), Tetrapleura (2), Thailentadopsis (3), Vachellia (c. 160), Viguieranthus (c. 23), Wallaceodendron (1), Xerocladia (1), Xylia (9), Zapoteca (20) and Zygia (c. 47). Uses: Fabaceae have a wide range of uses, including food, aphrodisiacs, agroforestry, beads, biofuel, boats, boxes, bridges, brooms, buttons, cabinetry, canoes, carpentry, char coal, climate mitigation, construction, coppicing, cosmetics, crates, dental floss, docks, dyes, ecological restoration, fertiliser, fibre, firewood, flooring, fodder, furniture, garden ornamentals, glue, gums, honey, insecticides, lacquers, lubricants, medicines, musical instruments, paper, perfumes, poisons, reforestation, rope, roof shingles, shade trees, shore protection, soap, soil stabilisation, sorcery, sewing needles, spices, tanning, utensils, veneers, Abrus precatorius, pods and seeds, Seychelles [176]

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Saraca indica, Hong Kong, China [176]

weaponry, witchcraft etc. Here, we have selected economically important and some remarkable usages and grouped the species accordingly. Pulse and vegetable crops: soybean (Glycine max) was an important crop in China before written records and was domesticated from wild G. soja in East Asia, the oldest records being from 2,000-year-old archaeological sites in Korea. It is now the most economically important legume crop in the world. The USA, Brazil and Argentina are the biggest soybean producers, but only a small proportion of the crop is directly consumed by humans, most being used as animal feed usually on an industrial scale. However, soya is used in a great number of processed foods (soy lecithin as a stabiliser), and of course it forms the basis of soy sauce, soy milk, tofu, miso, natto and tempeh, foods of increasing importance in vegetarian diets. The marama bean (Tylosema esculentum) from southern Africa is also eaten and has oil-rich seeds that have a similar amount of protein as soybeans. Being perennial, droughtand poor-soil-tolerant, this species has great potential for cultivation in semi-arid lands as a sustainable, erosion-preventing, high-yield crop. When roasted the seeds taste like cashew or chestnut. Second to the soybean, the most important legume is the peanut or groundnut (Arachis hypogea). It was domesticated from the Neotropical A. monticola and was already cultivated in pre-Colombian times. Until 254

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Tamarindus indica, China (HS) [176]

1930, it was mostly used as animal fodder, after which use for human consumption was promoted in Europe and North America. Introduced into China in the 17th century, it is now a major part of Chinese cuisine, and China is the largest producer of the crop, followed by India and the USA. Eaten roasted or boiled, often ground into flour, as peanut butter (an Aztec invention popularised in the late 19th century), or pressed into oil, it finds a great variety of applications in cooking, soaps, cosmetics, polishes, paints and lubricants. Of course peanuts are also commonly used in snacks and confectionery such as candy bars, peanut butter cups and peanut brittle. The common or garden pea (Pisum sativum) is a major pulse and vegetable crop. Originally collected from the wild in Neolithic times, it was soon domesticated and became a staple of the vegetable garden. The dried seeds could be kept for a long time and were ground into flour or boiled into pea soup, keeping famine at bay during Mediaeval times. Fresh garden peas and immature pods (mange-tout or snow peas) were a luxury food in early modern Europe (15th to 18th centuries), and pea shoots are a recent culinary novelty. The village of Peasenhall in Suffolk, England, celebrates an annual Pea Festival in honour of this famous legume. The type species of the family, the broad or fava bean (Vicia faba), is native to the southern Mediterranean and southwestern and southern Asia but is now cultivated

Amherstia nobilis, cultivated in Singapore (WA) [176]

worldwide. It was an important part of the Mediterranean diet c. 6,000 years ago, together with lentils, peas and chickpeas. There are many varieties, those with larger beans being eaten when young and tender, and those with smaller harder seeds (often called field or horse beans) being used as animal food or in some Middle Eastern dishes. They can also be deep fried as a savoury, crunchy snack, known in Latin America as ‘habas’. Broad beans are an important part of local cuisine in many parts of the world, but the main broad bean producers are China, Ethiopia and England. Of American origin, Phaseolus species were already widely cultivated before Columbus reached the hemisphere. Most important is the common bean (Phaseolus vulgaris), which includes varieties that produce brown, white or yellow beans, kidney beans, black turtle beans, borlotti beans, flageolet beans, haricots, string beans, pea beans and pinto beans. Some are eaten dried, whereas others are eaten while the pods are still young as a vegetable (e.g. haricots verts). They are often canned or made into soups or sauces and are important in many traditional cuisines in the New and Old World. Other commonly cultivated Phaseolus species of which seeds and/or pods are eaten are the scarlet runner bean (P. coccineus), lima or butter bean (P. lunatus), year bean (P. dumosus) and tepary bean (P. acutifolius). The mainly Old World genus Vigna includes a number of bean species. Most

FABALES

EUDICOTS

important are the black-eyed pea (Vigna unguiculata var. unguiculata) and yardlong bean (V. unguiculata subsp. sesquipedalis), which are important in African and Asian cuisines. Other more locally used beans are the moth bean (V. aconitifolia), adzuki bean (V. angularis), urd bean (V. mungo), mung bean (V. radiata) and rice bean (V. umbellata). High in protein, the groundnut or bambara bean (Vigna subterranea) is a staple food in West Africa and is currently also frequently grown in Spain, Pakistan, China and Australia. Lentils (Lens culinaris) have been widely cultivated since Neolithic times and are still an important pulse crop. Seeds are eaten cooked or ground into flour or dhal. The largest producers are Canada, India and Australia. Lentils come in a number of varieties and colours including green, yellow, orange-red, brown and black. Chickpeas (Cicer arietinum) are a major crop also cultivated since the Neolithic (c. 3500 BC), and wild chickpeas have been carbon-dated to c. 6800 BC after being found in a Mesolithic cave in France. Chickpeas were widely grown in Ancient Greece and throughout the Roman Empire and have been popular ever since. Seeds can be eaten freshly cooked or made into flour or paste and are a key ingredient of hummus, falafel and other Middle Eastern, Iberian, Jewish, Burmese and Indian recipes. Yeheb nuts (Cordeauxia edulis), from Cassia fistula, Seychelles [176]

the Horn of Africa, taste like sweet chestnuts and are a good arid-land food crop. Other pulse and/or vegetable crops eaten locally are pigeon bean (Cajanus cajan), jack bean (Canavalia ensiformis), Moreton Bay chestnut (Castanospermum australe), Tahitian chestnut (Inocarpus fagifer), bonavist bean (Lablab purpureus), chickling vetch (Lathyrus sativus), lupine bean (Lupinus albus and L. luteus), pearl lupine (L. mutabilis), Kersting’s groundnut (Macrotyloma geocarpum), yam bean (Pachyrhizus erosus), Goa bean (Psophocarpus tetragononolobus), African yam bean (Sphenostylis stenocarpa) and asparagus pea (Tetragonolobus purpureus). The seeds of carob (Ceratonia siliqua), Kentucky coffee tree (Gymnocladus dioicus) and Bauhinia petersiana can be roasted and used as a coffee substitute. Seeds of “flamboyant” (Delonix) can be crushed and eaten as a snack, and seeds of the South African boer-bean (Schotia) can be eaten after cooking. Young sataw beans (Parkia speciosa) and néré (P. biglobosa) are frequently eaten in the Old World tropics as a vegetable. Seedlings of Medicago sativa are eaten as alfalfa sprouts, and the bean sprouts common in Asian cuisine are from Phaseolus aureus and other species. Edible pulp: many legumes produce pods that contain edible pulp surrounding the seed. Tamarind (Tamarindus indica) is native to East Africa, but was introduced into Asia in ancient times. The pods have an acid-sweet

pulp around the seeds that can be eaten raw but is frequently used in confectionery and as an ingredient of Asian and African cuisine, especially curries, sauces and pickles. The pulp is also fermented into drinks, and seeds are also edible, raw, cooked or pressed into oil. The bark and leaves can be used to produce a dye, it produces good wood and is a good bee fodder. Tannin yields are also high. It truly is a plant with many uses. The fruit of velvet tamarind (Dialium spp.) is similar to tamarind and used in chutneys. The icecream bean (Inga edulis) has an edible white pulp that is often eaten in the tropics and used to flavour desserts. Guayamochil (Pithecellobium dulce) and rain tree (Samanea saman) are frequently planted for shade and their edible pulp, which can be made into drinks. Fruits and seeds of Chilean palo verde or kumbaru (Geoffroea decorticans) are sweet and replace molasses in local cuisines. Beans of mesquite (Prosopis spp.) can be ground into flour and added to bread or made into jelly or wine. Carob (Ceratonia siliqua) is a cultigen originating in Arabia (derived from C. oreothauma) that has pods containing sugary pulp and gum, which were formerly sold as sweets and now as an alternative for chocolate; they are used as a food additive and in cosmetics, medicines, photographic film, adhesives, paints, ink and polishes. The pods are commonly used as fodder and pet food (for hamsters, rabbits etc.) and sometimes made into a flour for

Labichea lanceolata, Australian National Botanic Garden, Canberra [176]

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255

FABALES

Genista tinctoria, Ruissalo Botanical Garden, Turku, Finland [176]

EUDICOTS

Phaseolus coccineus, private allotment Kingston upon Thames, Surrey, UK [176]

diabetics. The seeds were highly valued and were the locust beans of the Bible, used as a measure of weight and the origin of the carat (200 mg) of jewellers, due to their regular size and weight. The fruit pulp of honey locust (Gleditsia triacanthos) is edible and used in locally brewed beers, and the edible leaves and sweet pulp of datach (Detarium senegalense) are eaten locally in Sub-Saharan Africa. Edible roots: tubers of jicama (Pachyrhizus erosus) are popular in Mexican cuisine and delicious eaten fresh or cooked. Tubers of potato bean (Apios americana), hog potato (Hoffmannseggia glauca) and prairie turnip (Pediomelum esculentum) are roasted and eaten in North America, and tubers of some Lathyrus species are also edible (e.g. L. montanus, L. ochrus, L. tuberosus). Kudzu (Pueraria spp.) has starchy edible tubers that are popular in Japan, but elsewhere it is often invasive, for example causing ecological havoc in southeastern North America. Spices and f lavourings: fenugreek (Trigonella foenum-graecum) is an important condiment for flavouring food, especially Indian curries. Liquorice roots (Glycyrrhiza glabra) have a somewhat sweet flavour and are used in confectionery, drinks and tobacco. Liquorice root was often sold by herbalists and was chewed to release the sweet juice. In candy, liquorice extract is commonly mixed with aniseed oil and sometimes with 256

Christenhusz, Fay & Chase

Pisum sativum, private allotment, Kingston upon Thames, Surrey, UK [176]

salmiak (ammonium chloride), especially in the Netherlands (drop), Denmark (lakrids) and Finland (lakritsi, salmiakki). In England, liquorice was first mixed with sugar to make Pontefract cakes. In its natural form, liquorice is frequently used in Italy and Spain as a mounth freshener and made into ice-cream and liqueurs. Bark and leaves of bumba (Scorodophloeus zenkeri) are used as a garlic substitute in Africa. Teas: grown on a commercial scale in South Africa, the chopped and fermented stems and leaves of redbush or rooibos (Aspalathus linearis) are used as an infusion (to calm the stomach, especially of babies) and sold as a herbal tea. Similarly, honeybush or heuningbos (Cyclopia intermedia and C. subternata) is marketed in health food shops as an alternative to tea. Edible flowers: leaves, flowers and pods of the orchid tree (Bauhinia variegata) are edible. It is a sacred plant of Buddhists and the floral emblem of Hong Kong. Flowers of redbud (Cercis canadensis) can be eaten fresh in salads or pickled. Flowers and young leaves of the pride of Burma (Amherstia nobilis) are also edible. This plant has only been found in the wild twice and is possibly extinct, but it is a highly valued ornamental tree and planted throughout the tropics. Gums: several species can be tapped for their resin or gum, most notably gum

arabic, the sap of Senegalia senegal, used in sweets, lozenges, thickeners, adhesives, inks, watercolour paints etc. Other species of Senegalia (e.g. Amritsar gum, S. modesta) and species of Acacia (A. dealbata, A. pycnantha), manna (Alhagi graecorum), Burkea africana, guar gum (Cyamopsis tetragonoloba) and Vachellia (V. gummifera, V. horrida, V. nilotica) also produce edible gums, often used as food additives. Copal (Copaifera sp.) and gum copal (Daniellia oliveri) produce a highquality resin used in medicine, varnishes, paint and lacquer and as biodiesel. Gum tragacanth (Astragalus gummifer) is used in a wide range of industries. Wallaba oil (from Eperua oleifera) and other oleo-resins from, for instance Gossweilerodendron, Guibourtia, Kingiodendron, Myrospermum, Myroxylon and Prioria, can be used to make incense. Seeds of Adenanthera pavonina produce an industrial lubricant. Soap and perfume: seeds of Gleditsia sinensis and Gymnocladus chinensis contain saponins and are used in Asia to make soap and for washing clothes. Flowers of needle bush, Vachellia farnesiana, produce a perfume called ‘cassie’, highly valued in the perfume industry. Flowers of a number of broom species (Genista, Cytisus and relatives) are also used to produce perfume. The fragrant seeds of cumaru or tonka bean (Dipteryx odorata), are high in coumarin and used as a flavouring.

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Dyes: indigo (derived from Indigofera arrecta, I. articulata, I. suffruticosa and I. tinctoria) is probably the best known vegetable dye. It was domesticated originally in India from where it was exported as a luxury item to the Roman Empire. It was used to dye silk and in early book printing. Indigo remained rare due to the availability of woad (Isatis tinctoria, Brassicaceae), which gives a similar blue. A traditional dye for tuareg robes, batik and other fabrics, it was taken to the Carolina Settlement in North America, where it was used to dye clothes, and from where it has been exported since the 18th century. Blue jeans, invented in the USA in the 1870s, were originally dyed with natural indigo. Dyer’s broom (Genista tinctoria) was formerly used in Europe to produce a bright yellow dye. Brazilwood, Paubrasilia (Caesalpinia) echinata, was harvested on a large scale giving the name to the country Brazil (a name given in reference to the colour of glowing coal). Sappanwood (Caesalpinia sappan), also sometimes called brazilwood, is also used as a dye, but originates in tropical Asia. Logwood

(Haematoxylum campechianum) contains haematoxylin, a source of a dark violet dye used in dying cotton, fur, leather, silk, wool and synthetic fibres; it is used additionally to stain nuclei in biological microscope slides. Peachwood (H. brasiletto) yields brasilin, a red dye. Many species yield dyes that are used locally, such as jeheb nut (Cordeauxia edulis, purple), yellow flamboyant (Peltophorum pterocarpum, yellow), Zuccagnia punctata (yellow), Griffonia spp. (black), sangre de drago (Pterocarpus tinctorius, red) etc. Tanning: a good number of species produce tanniferous bark, but especially divi-divi (Libidibia coriaria) and guayacán (L. paraguariensis) are used on an industrial scale for tanning leather. Other species used for tanning are Balsamocarpon brevifolium, Bauhinia variegata, Burkea africana, Dimorphandra mollis, Elephantorrhiza spp., Melanoxylon brauna, Piliostigma thonningii, Tachigali tinctoria, Tara spinosa, etc. Fodder, forage and green manure: due to the ability to fix nitrogen in their root nodules, many Fabaceae are employed to fertilise the

soil. Commercially, a number of species are available as green manure, plants grown and then ploughed into the soil as natural fertiliser. Well-known species for this purpose are bird’s-foot trefoil (Lotus corniculatus), yellow lupine (Lupinus luteus), lucerne (Medicago sativa), serradella (Ornithopus sativus) and clover (Trifolium spp.). Clover and lucerne (called alfalfa in North America) are also important fodder and forage plants, being cultivated to produce high-protein greens to feed to animals. Other popular fodder plants are calopo (Calopogonium mucunoides), creeping indigo (Lotononis bainesii), jigal tree (Lysiphyllum cunninghamii), sainfoin (Onobrychis viciifolia), Brazilian lucerne (Stylosanthes guianensis), sulla clover or Italian sainfoin (Sulla coronaria), bitter vetch (Vicia ervilla), common vetch (V. sativa), fodder vetch (V. villosa) etc. Some species of forage legumes can cause the disease known as bloat if animals are allowed to eat them in large quantities, particularly in spring. In this disease, proteins in the forage can cause the formation of a stable foam in the

Plants at war — Augustin Pyrame de Candolle (1778–1841) In 1824 Swiss botanist Augustin de Candolle started a world f lora called the Prodromus systemtatis naturae regni vegetabilis. Although it was never finished, 161 families and 58,000 species were described, and it was later continued by his son Alphonse and his grandson Casimir Pyrame de Candolle. Both were famous botanists in their own right and they also passed this tradition on to a fourth generation, as his great-grandson Richard Emile Augustin de Candolle became a botanist too. Augustin de Candolle believed that there were sharp discontinuities between natural catagories, contrary to some contemporary researchers like Jussieu, and he also advocated the struggle between plant species for nutrients and light, which he called ’nature’s war’. This later influenced Charles Darwin in developing his principle of natural selection as

the driving force behind evolution. He also discovered that several species could develop similar characteristics that were not present in their ancestors, a term later called analogy. This was of great importance in his classification of plants as he distinguished between morphological and physiological characteristics, allowing him to come to a better understanding of relationships. He also studied movement of plants, suggesting that an internal biological clock exists, a finding many scientists at the time were sceptical about, but which was proven to be correct nearly a century later. De Candolle described over 10,000 new species, more than any botanist. At least six times a genus Candollea was described during the 19th century, the oldest having been based on a species of Pyrrosia (Polypodiaceae), so Candollea is now a synonym of that genus. Candolleodendron brachystachyum is used for a species of Fabaceae. Candollea is also

Engraving of Augustin Pyramus de Candolle by Jules Pizzetta, Galerie des Naturalistes de Jules Pizzetta, ed. Hennuyer, 1893 (public domain)

the name of the botanical journal of the Botanical Garden of the city of Geneva, in honour of the important contributions of this botanical dynasty.

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Vicia faba, private allotment, Kingston upon Thames, Surrey, UK [176]

Hoffmannseggia glauca, New Mexico, USA (DZ) [176]

Glycine mas, private allotment, Kingston upon Thames, Surrey, UK [176]

rumen, stopping the animal being able to release the gases formed by fermentation/ digestion. If caught in time, the gas can be released by puncturing the rumen (as seen in the film Far from the madding crowd, based on the book by Thomas Hardy). In severe cases, the rumen can burst, leading to death of the animal. Species containing relatively high concentrations of condensed tannins (e.g. Onobrychis sativa and some Trifolium species) are sometimes advocated as a way of avoiding bloat, as the tannins precipitate the soluble proteins, but they also give a bitter taste to the forage making them less attractive to the animals. Agroforestry: many Fabaceae are important shade trees, especially for coffee plantations and other shade-loving crops. A special type of agroforestry is alley cropping, for which species of Inga (e.g. I. edulis) are especially suitable in Latin America, and trials with other genera such as Milletia and Lysiloma are under way in Africa. Alley cropping, in which Inga (or other Fabaceae) tree seedlings are planted in a series of hedgerows, is a sustainable alternative to slash and burn cultivation. The fallen Inga leaves create a thick layer of mulch, shading out weeds and exotic grasses, and the nitrogen-fixing nodules on the roots enrich the soil. After two years, the Inga hedgrows are coppiced, the leaves used as mulch, the branches for firewood near the homestead (tackling further deforestation for that purpose), and a crop can then be planted in the alleys between the coppiced hedgerows. Once the crop is harvested, the

Inga plants grow tall until the next planting season, hence recycling the nutrients and preventing erosion at the same time. For more information, see the webpages of the Inga Foundation: www.ingafoundation.org. Brooms and fibre: Cytisus scoparius, or common broom, is grown as an ornamental and soil stabiliser and for perfume and dyes, but it received its name from the broom-like branches that can be easily made into brooms and were used frequently for that that purpose in the past. Other species of Cytisus, Genista, Spartium and Ulex have also been used as brooms. Sunn hemp (Crotalaria juncea) yields a high-quality bast fibre for cordage and fine paper, and there are numerous other species that are locally important fibre crops. Wood: as many species are dominant members of tropical forests, the family is an important source of wood for local communities, used for construction, turning, furniture, firewood and charcoal. Many species are cultivated commercially for their hard wood, the species being too numerous to list here. Plantations of Robinia pseudoacacia in the temperate zones supply these regions with durable hardwood to reduce the global demand for tropical hardwood timber and hopefully indirectly preserve some rainforests. However, some tropical species are still extensively harvested for their hard and durable wood. Truncheons of London policemen were once made of West Indian ebony (Brya ebenus) because it takes a smooth, high, black polish. The oily wood of umthiza, Umtiza listerana, could

be turned into self-lubricating propeller shafts. Rosewood (Dalbergia) is harvested extensively from the wild for its scented wood valued by the perfume industry. Plantations have now been established, but threats to wild populations remain. International trade of D. nigra, the most threatened species, is now controlled by CITES. Beads: several species have attractive seeds, often bright red or red with a black spot, and are used to make beads and buttons. Most popular species are the red bead tree (Adenanthera pavonina), the prayer bead vine (Abrus precatorius), chamfuta (Afzelia quanzensis), sea hearts (Entada spp.), the lucky bean tree (Erythrina spp.), the nicker bean (Guilandina bonduc), jumby bead (Ormosia spp.) and the rosary bean (Rhynchosia spp.). Some of these are extremely poisonous (e.g. Abrus precatorius), so care should be taken if jewellery made with these is handled. Hallucinogens, medicine and poison: despite the large number of species with edible seeds, Fabaceae include many species containing complex compounds, many of which are medicinal, hallicinogenic or poisonous. Seeds of cohoba (Anadenanthera peregrina), and to a lesser extent Dimorphandra parviflora, are crushed to make an intoxicating snuff in Latin America, frequently used in shamanic rituals. The seeds of Madagascan Lemuropisum edule are edible when young, but become poisonous when ripe. Sweet peas (Lathyrus odoratus) are grown for their flowers, but the seeds are poisonous and should not be confused with edible peas.

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EUDICOTS

Kennedia, Lablab, Laburnum, Lathyrus, Lespedeza, Lotus, Lupinus, Maackia, Mimosa, Neptunia, Parkinsonia, Robinia, Samanea, Saraca, Senna, Sophora, Strongylodon, Styphnolobium, Swainsona, Thermopsis, Virgilia and, of course, Wisteria are cultivated as ornamentals. Acacia dealbata is sold as a cut flower called ‘florist’s mimosa’.

Pachyelasma tessmannii and Erythrophleum suaveolens were used as fish poison and the latter also as a penal punishment in the past. Roots of Abrus precatorius (crab’s eye or prayer beads) can be used as a drink sweetener or alternative to liquorice but are mildly toxic. Additionally, many species contain insecticidal alkaloids, such as Derris elliptica and Gymnocladus dioica, and are used to protect crops and kill mosquitoes. Several species produce medicinally important compounds, useful in treatments of many diseases, including cancer, diabetes and malaria, but these are too numerous to list here. Ornamentals: many species of Fabaceae are grown as ornamentals, in perennial borders and as street and shade trees. Best known for its scented flowers (but poisonous seeds!) is perhaps the sweet pea (Lathyrus odoratus). Most commonly, members of the genera Acacia, Albizia, Amherstia, Amorpha, Anthyllis, Argyrocytisus, Baptisia, Bauhinia, Brownea, Caesalpinia, Calliandra, Caragana, Carmichaelia, Cassia, Ceratonia, Cercis, Chorizema, Cladrastis, Clianthus, Clitoria, Coronilla, Cytisus, Dalea, Delonix, Dorycnium, Erythrina, Erythrostemon, Galega, Gleditsia, Gliricidia, Gymnocladus, Hardenbergia, Hippocrepis, Hovea,

Giant beans: There are record holders among Fabaceae. Tualang (Koompassia excelsa) is, at 88 metres, one of the tallest eudicots, only surpassed by Eucalyptus regnans (Myrtaceae). The monkey ladder (Entada gigas) has pods that can grow up to two metres long and 12 cm across, holding up to 15 seeds, each c. 6 cm across. However, these are not the largest seeds, giant nato (Mora megistosperma) has the largest seed of any eudicot, measuring c. 12 by 18 cm. The seeds of oil nato (Mora oleifera) have the largest embryo of any eudicot seed. It can be up to a kilogram in weight and is as such similar to that of the monocot coco-de-mer (Lodoicea maldivica, Arecaceae). Remarkably, the large seeds of Mora and Entada are distributed by water currents. They float due to an air-filled cavity between the cotyledons; in contrast, the largest but heavy seeds of coco-de-mer (Lodoicea, Arecaceae) sink.

Lupinus nootkatensis, Helsinki Botanical Garden, Finland [176]

Ceratonia siliqua, Gibraltar [176]

Plant movement: Many species of Fabaceae have ‘sleeping’ leaves that fold and droop when night falls and revive in the morning. Not many plants move quickly enough to enable plant movement to be observed by the human eye, but the sensitive plant or touch-me-not (Mimosa pudica) has leaves that do this quickly in response to being touched or shaken, reopening minutes later. This movement is caused by an electric current that causes the turgor in cells of the petioles to change so that the leaflets fold inwards. It is not exactly known why this has evolved, but it is thought to be a response to predation by herbivores. Water mimosa (Neptunia oleracea) is an aquatic legume that also has leaves that close after touching. Another species with rapid movement is the semaphore plant (Codariocalyx motorius), but the leaves of this species move in response to the intensity of sunlight, not touch. Etymology: Faba is the Latin form of the Proto-Indo-European bhabh, a bean. Faba vulgaris is a later synonym of Vicia faba, the currently accepted name for broad bean. An alternative name for this family is Leguminosae, based on the type of fruit called a legume or bean pod. Indigofera ammoxylum, Réunion Botanical Garden [176]

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FABALES

EUDICOTS

Suriana maritima, Yucatán, Mexico [177]

Guilfoylia monostylis in fruit, Royal Botanic Gardens, Melbourne, Australia (CD) [177]

Suriana maritima in fruit, Guadeloupe [177]

Stylobasium spathulatum, Karijini National Park, Western Australia [177]

177. SURIANACEAE

clawed. The ten stamens are all fertile or the inner whorl of five sterile staminodes often reduced in number. Filaments are free, and the basifixed anthers open by a lengthwise slit. The superior ovary is sessile or stalked (in Recchia) and composed of one to five distinct carpels, each with a gynobasic style topped with a clavate to capitate stigma. Fruits are composed of one to five drupe- or nut-like monocarps (drupetum or achenetum).

well. Molecular analysis revealed that they are sister to Polygalaceae in Fabales; they share an apocarpous gynoecium with Quillajaceae, which is reduced to a single carpel in Fabaceae. A single fossil of Suriana from the Eocene of Wyoming is known, but molecular dating estimates that the family is c. 40 million years old. Stylobasium is windpollinated and was previously placed in its own family due to lack of synapomorphies with any taxon. Molecular analyses have placed it here.

Bay-cedar family

These are trees and shrubs with simple or pinnately compound alternate leaves that are petiolate or sessile. Stipules are small or absent. Inflorescences are terminal or axillary cymes or panicules, sometimes solitary in the leaf axils or borne on branches (cauliflorous), usually with bracts and bracteoles. The actinomorphic flowers are bisexual, sometimes unisexual, and have usually five (to seven) free, persistent sepals. The usually five petals (absent in Stylobasium) are free and sometimes 260

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Distribution: Due to the wide distribution of Suriana maritima along tropical coasts, the family occurs in the Caribbean, Indian Ocean islands, Malesian Archipelago and Pacific islands. Recchia is endemic to Mexico, and the remaining genera are only found in Australia. Phylogeny and evolution: Previously assigned to Simaroubaceae or Chrysobalanaceae, they were found to have numerous characters that did not match these families

Genera and species: Surianaceae include five genera with a total of eight species: Cadellia (1), Guilfoylia (1), Recchia (3), Stylobasium (2) and Suriana (1). Etymology: Suriana is named for French physician and apothecary Joseph Donat Surian (died 1691), who collected plants with Michel Bégon and Charles Plumier during an expedition to Haiti and Martinique.

FABALES

EUDICOTS

This is a family of perennial and annual herbs, shrubs, vines, trees (up to 50 m

in Xanthophyllum) and achlorophyllous mycoheterotrophic herbs (Epirixanthes). Stems are mostly round, but sometimes angular or winged, and branches can be tipped with spines. Leaves are alternate, opposite or in whorls, simple, petiolate or not, and blades have pinnate venation and entire margins. They are rarely reduced and scale-like (Epirixanthes). Stipules are absent, rarely spine- or scale-like. Inflorescences are terminal or axillary, simple or compound racemes or panicles (rarely f lowers can be solitary), with bracts and bracteoles subtending flowers. The zygomorphic flowers

Polygala vulgaris, Ireland [178]

Comesperma calymega, Mt Lesueur, Western Australia [178]

178. POLYGALACEAE Milkwort family

Polygala ehlersii, Taita Hills, Kenya [178]

are bisexual, pedicellate or sessile. The five sepals are free, partly fused at the base or fused into a tube, the outer three small, inner two (wings) large, petal-like, or all five nearly equal and petal-like. The three or five petals are free or basally fused, the lower one boat-shaped (keel), entire or trilobed, sometimes with an apical crest or fimbriate/ lamellate appendages. Stamens are usually five to eight (sometimes as few as two or upto ten), with free or variously united filaments and then forming a sheath open on the upper side, fused to the corolla lobes. The basifixed anthers usually open by a single apical pore.

Monnina crassifolia, Ecuador [178]

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FABALES A nectary disk is usually absent, but if present it is annular or glandular. The superior ovary is composed of two to eight carpels fused into one or two locules. The single style is erect or curved with one or two capitate stigmas. Fruits are capsules that open by valves, unilocular samaras or a fleshy drupes. Distribution: This family has a nearly worldwide distribution (absent from the Sahara and higher latitudes). They are especially diverse in tropical and subtropical regions of both hemispheres. Phylogeny and evolution: Previously placed either in their own order or in Malpighiales, the latter now known not to be correct. Molecular studies placed this family close to Surianaceae and Fabaceae in Fabales, with which they share few morphological characters, apart maybe from floral development. The family diversified during the Triassic, probably in response to the evolution of elaiosomes, which allow mutualism with ants for seed

EUDICOTS

dispersal. The genera are not all well defined. Bredemeyera and Polygala are polyphyletic and are in the process of being recircumscribed. Xanthophyllum, in the past often placed in its own family, is sister to the rest of Polygalaceae. Epirixanthes is mycoheterotrophic, otherwise unknown in the family and order; mycoheterotrophy is rare in eudicots in general. Genera and species: Polygalaceae include c. 26 genera (possibly more) and about 900 species: Acanthocladus (8), Asemeia (28), Atroxima (2), Badiera (c. 25), Balgoya (1), Barnhartia (1), Bredemeyera (c. 60), Caamembeca (15), Carpolobia (4), Comesperma (40), Diclidanthera (4), Epirixanthes (5), Eriandra (1), Gymnospora (2), Hebecarpa (9), Heterosamara (17), Monnina (c. 150), Moutabea (8), Muraltia (119), Phlebotaenia (3), Polygala (c. 275), Polygaloides (1), Rhinotropis (17), Salomonia (3), Securidaca (80) and Xanthophyllum (94).

Uses: The family is of little economic importance, apart from use in local herbal medicine. The beni seeds of Polygala butyracea, after heating and frying, can be made into malukang butter added to soups and meat dishes. Fibre of the bark of this species is made into thread used for weaving and basketry. Seeds of Securidaca longipedunculata are ground and used in soup in West Africa. Roots of Polygala arillata are fermented into an alcoholic drink in Nepal. Drupes of Carpolobia and Muraltia are sometimes eaten in Africa, and berries of Monnina have antifungal properties useful as a natural anti-dandruff shampoo and can be used for dyeing. Xanthophyllum produces a fine wood. Etymology: Polygala (πολυγαλα) is the classical Greek name for the plant. It is derived from πολύς ( polys), much, and γάλα (gala), milk, because it was assumed that animals that ate this plant would give more milk.

ROSALES Families 179 to 187 make up Rosales, the sister clade to Fagales and Cucurbitales. They are dated to have diversified c. 76 million years ago, but older estimates (up to 103 million years) are also published. It is a large order containing c. 2% of eudicot diversity. The order shows a clear development toward the loss of petals and wind pollination, occuring independently in several lineages. Most species have associations with ectomycorrhizal fungi and many with nitrogen-fixing bacteria.

179. ROSACEAE Rose family

These are annual and perennial herbs, shrubs and trees, often with spiny branches. Leaves are usually alternate, sometimes in

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basal rosettes, or distichous, rarely opposite (Lyonothamnus, Rhodotypos). Blades are entire to pinnately or palmately compound, often toothed or lobed along the margin with pinnate or palmate venation. Stipules are usually present and often fused with the petiole. Inf lorescences are usually terminal compound racemes but can be variously cymes, corymbs, false umbels or solitary flowers in leaf axils. The usually bisexual (sometime unisexual) flowers are actinomorphic, with a receptacle forming a flat, concave or tubular hypanthium bearing sepals, petals and stamens on the outer or upper margin. An epicalyx formed of fused

bracts is often present. The usually five (sometimes four to six) sepals are free or partly fused to the ovary. Petals are as many as sepals or absent in some genera. Stamens are usually numerous, rarely reduced to one or two, the filaments are normally free and anthers open by lengthwise slits. The usually semi-inferior, sometimes inferior or superior, ovary is usually adnate to the calyx tube and composed of one to many (often five), fused or free carpels forming one to several locules. The styles are free or fused into a single branched style. Fruits are variable, fleshy or dry, of one or more achenes, drupes, pomes, hips, follicles or capsules, the hypanthium

ROSALES

EUDICOTS

sometimes coloured and fleshy, sometimes the dry fruits bearing a feathery, persistent style for wind dispersal. Distribution: This cosmopolitan family is only absent from permanently frozen regions and dry habitats in Africa and Australia. They are most diverse in the temperate zones and less diverse in the lowland tropics. Phylogeny and evolution: The family is c. 76 million years old. Eocene Prunus seeds are known from China; the stem group of Pyrinae has been dated to c. 60 million years, and there was substantial divergence in that group during the Eocene and Oligocene. The taxonomy of the family has been problematic due to apomixis and hybridisation (difficult species concepts) and excessive splitting at the generic level of temperate genera of economic importance. Many genera such as Sorbus and Potentilla are polyphyletic in their traditional sense, due to the separation of economic genera such as Malus, Pyrus and Fragaria. Hybrids occur often between genera, making these difficult to keep separate. Genera are therefore in great need of recircumscription. A broad generic concept would be the easiest solution to the convoluted nomenclature in these groups, as in the formerly highly divided genus Prunus (now including the former genera Amygdalus, Armeniaca,

Rosa ‘Centifolia’, Royal Botanic Gardens, Kew, UK [179]

Cerasus, Laurocerasus, Maddenia, Padus, Persica and Pygeum). Mespilus is embedded in Crataegus, with which it makes fertile hybrids, and Neillia includes Stephanandra. The status of Poterium as separate from Sanguisorba and acceptance of Bencomia, Marcetella, Dendriopoterium and Sarcopoterium are not at all clear. Geum includes Acomastylis, Coluria, Novosieversia, Oncostylus, Orthurus, Taihangia and Waldsteinia. Potentilla should include Alchemilla, Aphanes, Comarella, Comarum, Dasiphora, Dr ymocallis, Duchesnea, Fragaria, Horkelia, Horkeliella, Ivesia, Lachemilla, Pentaphylloides, Potaninia, Purpusia, Schistophyllidium, Sibbaldia, Sibbaldianthe, Sibbaldiopsis, Stellariopsis, Tormentilla and Zygalchemilla, which would make this one of the larger genera of vascular plants (c. 1,350 species). Also Pyrus should be expanded to comprise c. 465 species and include Aria, Aronia, Chaenomeles, Chamaemelum, Chamaemespilus, Cormus, Cotoneaster, Cydonia, Dichotomanthus, Docynia, Docyniopsis, Eriobot r ya, Eriolobus, Hesperomeles, Heteromeles, Malus, Macromeles, Micromeles, Osteomeles, Photinia, Pseudocydonia, Pyracantha, Rhaphiolepis, Stranvaesia, Torminaria and Sorbus (to avoid a polyphyletic Sorbus), but these nomenclatural changes are highly unpopular due to the common application

Potentilla (Fragaria) virginiana, Helsinki Botanical Garden, Finland [179]

of many of these names. Taxonomic combinations have often not yet been made. Genera and species: Rosaceae include about 54–75 (to c. 90, depending on delimitation) genera with about 2,950 species (excluding the thousands of apomictic species in some genera). Following molecular phylogenetics, they are divided into three subfamilies: Rosoideae – Acaena (c. 100), Agrimonia (c. 13), Alchemilla (c. 1,000), Aremonia (1), Bencomia (7), Chamaerhodos (5), Cliffortia (120), Fallugia (1), Filipendula (15), Geum (c. 55), Hagenia (1), Leucosidea (1), Margyricarpus (8), Parageum (6), Polylepis (c. 20), Potaninia (1), Potentilla (c. 330), Rosa (c. 125), Rubus (c. 250), Sanguisorba (c. 15), Sarcopoterium (1), Sieversia (1) and Spenceria (1); Dryadoideae – Cercocarpus (5), Chamaebatia (2), Dryas (2) and Purshia (7); Spiraeoideae – Adenostoma (2), Amelanchier (c. 20), Aronia (c. 15), Aruncus (1), Chaenomeles (3), Chamaebatiaria (1), Chamaemeles (1), Coleogyne (1), Cotoneaster (c. 260), Crataegus (142), Cydonia (1), Dichotomanthes (1), Docynia (1), Eriobotrya (c. 17), Eriogynia (1), Eriolobus (1), Exochorda (1), Gillenia (2), Hesperomeles (11), Heteromeles (1), Holodiscus (1), Kageneckia (3), Kelseya (1), Kerria (1), Lindleya (2), Lyonothamnus (1), Macromeles (4), Malus (c. 40), Neillia (15), Neviusia (1), Oemleria

Potentilla erecta, Lake District, England, UK [179]

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ROSALES

EUDICOTS

(1), Osteomeles (1), Petrophytum (3), Photinia (c. 50), Physocarpus (10), Prinsepia (4), Prunus (c. 200), Pseudocydonia (1), Pyracantha (3), Pyrus (c. 15), Rhaphiolepis (5), Rhodotypos (1), Sibiraea (4), Sorbaria (4), Sorbus (c. 135), Spiraea (c. 80), Spiraeanthus (1), Vauquelinia (3) and Xerospiraea (1). Uses: The economic importance of this family lies mainly in the fruits of many species. Apples, peaches, pears and cherries are among the most commonly grown tree fruits and are popular around the world. Almonds (Prunus dulcis) have sweet or bitter seeds that have been cultivated in the eastern Mediterranean since ancient times, domesticated almonds appearing in Early Bronze Age archaeological sites (c. 2,500 years old). Sweet seeds (var. dulcis) are used raw or toasted for confectionery, desserts, snacks, baked goods, marzipan, macaroons, almond milk, almond butter etc. Cheap processed food that includes almonds often have this adulterated with the more bitter seeds of apricot or peach. Sweet almonds are the most commonly grown nut for human consumption, the largest production being in California, the Mediterranean and Iran. Bitter almond (P. dulcis var. amara) is used medicinally, for eardrops and in hair lotion, but this has led to some accidental cases of poisoning. Almond oil is made from either Rubus phoenicolasius in fruit, Manhattan, New York, USA [179]

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sweet or bitter almonds and used for cooking, a massage oil and medicinally. The seeds (like many other species of Rosaceae) contain the glycoside amygdalin, which after crushing or chewing of the seeds is transformed into the deadly prussic acid (hydrogen cyanide). This compound is found in low concentrations in modern sweet almond cultivars, but in high concentrations in bitter almonds, which can cause cyanide poisoning when eaten. Edible seeds of wild almond (Prunus webbii) were used in Greece before sweet almonds were introduced. Prunus also includes a number of commonly grown fruits. Best known is the peach (P. persica), which is one of the most widely grown tree fruits. It is a cultigen probably derived in China from P. davidiana, and there are many cultivars, including P. persica ‘Saturn’, the doughnut peach or paragueiro. Similar to almonds, the seeds are ground and used in Italian sweets and liqueur (amaretto). Nectarine (P. persica var. nucipersica) originated as a spontaneous mutant of peach trees, producing fruits with smooth skins. The apricot (P. armeniaca) has been cultivated in northern China since 2000 BC, although this has been disputed and a less likely Indian or Armenian origin has also been suggested. The fruit is rich in vitamin A, and it is eaten fresh, tinned or dried and

Rosa canina, Wavrons, France [179]

is made into jams and cakes, or used as flavouring for liqueur or brandy. The oil of the seed is commonly used in the cosmetics industry. Similarly used is the scented oil of Briançon apricot (P. brigantina). The plum (P. domestica) is also a cultigen of complex hybrid origin, probably involving cherry plum (P. cerasifera) and sloe (P. spinosa), but it is often hybridised in America and Asia with local native species such as P. salicina. Damson or bullace (Prunus insititia) is often considered a subspecies or variety of P. domestica, but sweet forms are sometimes called mirabelles and should not be confused with the cherry plum. Mirabelles (or myrobalan plum = ‘fragrant acorn’) or cherry plum (P. cerasifera) are native to Eurasia and also frequently planted and locally eaten, either unripe or ripe, often cooked or stewed into jams or preserves. Greengage (P. domestica subsp. italica), a delicious fruit on its own, is hybridised with apricots to create plumcots or pluots. The sweet cherry (P. avium) is usually eaten fresh and is commonly available. Sour cherry or morello (P. cerasus) is the cooking cherry, usually made into jams, pies, drinks and juices and used in certain Belgian beers (kriek). The species is of unknown origin, but it is hybridised with sweet cherries to give Duke cherries (P. ×gondouinii), which are sweeter but cook better. Traverse City (Michigan, USA) is nicknamed the ‘Cherry Rosa amblyotis in fruit, Helsinki Botanical Garden, Finland [179]

ROSALES

EUDICOTS

Sarcopoterium spinosum, Lebanon [179]

Cydonia oblonga, Ioannina, Greece [179]

Capital’, due to the large numbers of cherry orchards in that region. Minor fruits of Prunus include American plum (P. americana), chicasaw plum (P. angustifolia), Oregon cherry (P. emarginata), hortulan plum (P. hortulana), beach plum (P. maritima), ume or Japanese apricot (P. mume), wild goose plum (P. munsoniana), Canada plum (P. nigra), Chinese plum (P. salicifolia), rum cherry (P. serotina), apricot plum (P. simonii), sloe (P. spinosa), Nanking cherry (P. tomentosa) and chokecherry (P. virginiana). Sloes (P. spinosa) are still widely collected in Britain and made into sloe gin. Ume fruit is often salted in East Asia. The leaves and flowers of several cherry species are pickled in salt in Japan or are used to flavour sweets or tea. Many wild apples are known from Neolithic times, and they were often stored dried as food during the winter. The orchard apple (Malus pumila), now one of the most widely grown fruit trees, is derived from various wild species. There are currently some 2,500 cultivars of apples, of which ‘Braeburn’, ‘Bramley’, ‘Cox’s Orange’, ‘Elstar’, ‘Fuji’,

Petrophytum cinerascens, Royal Botanic Gardens, Kew, UK [179]

‘Gala’, ‘Golden Delicious’, ‘Granny Smith’, ‘Jonagold’, ‘McIntosh’ and ‘Red Delicious’, are among the most widely grown. Asian crab apple, Malus baccata, is sometimes used in hybridisation to enhance cold-hardiness of apples. Apples have a variety of uses: they are eaten fresh or cooked in baked goods and confectionery, boiled into syrup, made into calvados, cider or vinegar or dried. Malic acid and pectin, derived from apples, are common food additives. Pears (Pyrus communis) are also a widely grown fruit with over 1,000 cultivars. They are native to Eurasia, especially the Caucasus, and can be distinguished from apples (Malus) by having stone cells in their flesh, making the flesh gritty. Pears are often eaten fresh as a table fruit and are sometimes dried or cooked into purée, juice or syrup. Perry, the equivalent of apple cider made from pears, was previously popular in Britain. Vinegar is produced from pears in Western Australia. The Asian or nashi pear (P. pyrifolia) is a species from subtropical China often grown in the tropics and subtropics.

Sorbus species are more commonly used for their wood, but several species have edible fruits, most notably the Whitty pear or true service tree (S. domestica) and the wild service tree (S. torminalis), which have fruit edible after bletting (exposure to frost), whitebeam (S. aria), the fruits of which are used as a flavouring for brandy, and rowan or mountain ash (S. aucuparia), the berries of which can be cooked into jellies, although these can be too astringent for most people. Rowan jelly is a traditional accompaniment for venison. The common strawberry is Potentilla ×ananassa (formerly Fragaria), an octaploid hybrid of P. chiloensis from western North and South America and P. virginiana from the east. Many species are hybridised with other species of Potentilla to create numerous cultivars with different flavours. The garden strawberry in Europe before discovery of the Americas was the hexaploid musk strawberry (P. moschata), frequently depicted on Mediaeval tapestries. The woodland strawberry (P. vesca) is rarely cultivated but Plants of the World

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ROSALES

EUDICOTS

is commonly collected in northern Europe. Hybrids with the garden strawberry have resulted in large fruited cultivars with the wild taste (P. ×vescana). The Indian strawberry (P. indica, Duchesnea indica) produces insipid berries but is grown for ornament. Roots and leaves of silverweed (Potentilla anserina) were formerly used cosmetically to reduce skin spots and in suntan lotion; leaves were placed in shoes to reduce sweating. Rubus is another important fruit genus, which includes raspberries (R. idaeus), blackberries (including R. fruticosus, R. corylifolius, R. plicatus, R. ulmifolius and their apomictic derivatives) and cultivars, many of which are hybrids with other species (e.g. boysenberry, loganberry, silvaberry, sunberry, tayberry, tummelberry and veitchberry). Minor fruits usually collected in the wild include Alleghany blackberry (R. alleghaniensis), Arctic raspberry (R. arcticus), European dewberry (R. caesius), cloudberry (R. chamaemorus), cheeseberry (R. ellipticus), American dewberry (R. flagellaris), Andes berry (R. glaucus), Mysore raspberry (R. niveus), black raspberry (R. occidentalis), wineberry (R. phoenicolasius), roseleaf bramble (R. rosifolius), salmonberry (R. spectabilis) and Pacific dewberry (R. vitifolius). Fruits are eaten fresh or used to make jams, juices, confectionery, baked goods, flavourings and liqueurs. Cercocarpus traskiae, Santa Catalina Island, California, USA [179]

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The quince (Cydonia oblonga) is native to Anatolia and has been cultivated since ancient times. It makes a good jelly because of its high pectin content. Quinces can also be eaten after bletting. In antiquity the quince was considered a love-token and probably is the source of the golden apples of the Hesperides in Greek mythology, used in the judgment of Paris and causing the Trojan wars. The name marmalade was originally used for quince jam, derived from the Portuguese name for this fruit (marmelo). It is also fermented into a sweet, alcoholic wine and is the main ingredient for ‘mostarda di fruta’ in Italy and ‘membrillo’ in Spain. The astringent fruit of Chinese quince (Pseudocydonia sinensis) can be used like European quince. Fruit of other species including Japanese quince (Chaenomeles speciosa) and C. cathayensis can be made into jellies or added to apple sauce. Medlar (Crataegus germanica, formerly Mespilus germanica) can be eaten after frost when it is slightly rotted (bletted). Fruit of azarole (C. azarolus) tastes like apple, Chinese hawthorn (C. pentagyna) is grown as a fruit tree in China and black hawthorn (C. douglasii) is used for jelly in North America. Japanese medlar, loquat or nispero (Eriobotrya japonica) has fruit that is often eaten fresh or made into preserves. Other minor fruits are serviceberry, juneberry

Dryas octopetala, Royal Botanic Gardens, Kew, UK [179]

or saskatoon (Amelanchier spp.) and black chokeberry (Aronia melanocarpa), which are often eaten fresh or dried. Oso-berry (Oemleria cerasiformis) also has edible fruit. Redbead cotoneaster (Cotoneaster racemif lorus) is the source of a sweet substitute for manna that is high in dextrose and used in Iran and India. Inflorescences of burnet (Sanguisorba officinalis) were formerly used to make wine in England. Kageneckia lanceolata leaves yield a black dye, and the bark of Rhaphiolepis umbellata is a source of brown dye. Some species produce good wood, e.g. Cercocarpus, Crataegus, Eriobotrya, Malus, Polylepis, Prunus, Pyrus and Sorbus. Sarcopoterium spinosum is a spiny bush common around Jerusalem and was possibly used to make the crown of thorns worn by Jesus Christ. A sugar alcohol, sorbitol (E420), is found in many Rosaceae and only slowly metabolises in the human body, making it a good alternative to sugar. It is commonly found in apples, pears etc., but is now commercially made from corn syrup and commonly used in diet foods and sugar-free products. Another well-known compound originally extracted from Rosaceae (meadowsweet or swampspiraea, Filipendula ulmaria) is acetylsalicylic acid, better known as aspirin (“a” from acetyl and “spir” from Spiraea). Prunus persica, in fruit, Santa Barbara, California, USA [179]

ROSALES

EUDICOTS

Filipendula ulmaria, Lake District, UK [179]

Gillenia trifoliata, private garden, Kingston upon Thames, Surrey, UK [179]

Essential oils of roses are used for perfume and scent-making, and a jam is made of the flowers, especially R. ×centifolia. Musk-rose (Rosa moschata) is used for rose water in Iran and R. ×odorata (R. chinensis × R. gigantea) is used in scented teas. Roses became symbols of nationalism, as in the War of the Roses, the red rose of Lancaster (R. gallica ‘Officinalis’) and the white rose of York (R. ×alba ‘Semiplena’). The burnet rose (R. spinosissima) is a symbol of midsummer in the Nordic countries. Rose hips used in jam, tea and syrup are harvested from dog rose (R. canina) and eglantine (R. rubiginosa), although care must be taken to remove the seeds as these are covered in irritating hairs. Locally, fruits of other rose species are eaten as well, notably the hips of R. woodsii and Japanese rose (R. rugosa). Roses are well known as ornamental plants, and a great number of cultivars have been produced, varying from bushy and creeping to tall and climbing varieties, some scented, some not, some short stemmed for gardens, some long-stemmed and important in the cutflower industry (currently mostly concentrated in the Netherlands, Kenya, Ethiopia, Colombia and Ecuador). Roses were early symbols of secrecy, mystery and virginity. They have been in cultivation since at least 484 BC, when Herodotus discussed double-flowered

forms, but they were already grown in ancient China and are figured on Minoan murals at Knossos (R. ×richardii). The thousands of cultivars are of such complex origins that a formal classification of roses is difficult, if not impossible. Rosa aside, many other rosaceous genera are popular garden plants, some with numerous horticultural cultivars, especially the genera Acaena, Alchemilla, Aronia, Aruncus, Chaenomeles, Cotoneaster, Crataegus, Dryas, Exochorda, Geum, Gillenia, Holodiscus, Kerria, Malus, Neillia, Photinia, Potentilla, Prunus, Pyrus, Rhaphiolepis, Rubus, Sanguisorba, Sorbaria, Sorbus and Spiraea. Flowering cherries (Prunus ×yedoensis and P. ‘Sato-Zakura Group’) are the national flower of Japan, and many additional cultivars are derived from P. serrulata. Laurel cherries (P. laurocerasus and P. lusitanica) resemble bay (Laurus nobilis, Lauraceae) and are often planted to the same effect; they are so similar to the leaves of laurel that they are even used in “laurel” wreaths, but they are poisonous and should not be used in cooking. Record: At 5,100 m in the Bolivian Andes, trees of Polylepis tarapacana can be found, which is the highest elevation for any tree to grow.

Pyrus amygdaliformis, Royal Botanic Gardens, Kew, UK [179]

Carnivory: Many members of Rosaceae are covered with glandular, often sticky hairs or extraf loral nectaries. Insects often become entrapped in these, and it has widely been assumed that these glands have a defensive capability. However, members of the Potentilla arguta complex (sometimes placed i n Dr ymocallis, including P. glandulosa and P. rupestris) appear capable of not only trapping insects but also of digesting them and absorbing the released nutrients. These species occur in habitats that support other carnivores, especially Drosera, and fit the syndrome of conditions associated with carnivory, but surface microbes as the source of the detected digestive enzymes cannot be ruled out. Rosehip cruelty: Until at least the 1960s, school children in northern England used to torment each other by putting seeds from rosehips down the backs of their shirts, taking cruel advantage of the irritating hairs. Etymology: Rosa is the Latin name for a rose, possibly derived from the Greek rhodon (ρόδον), a rose, but how this was derived remains a mystery. It possibly has an ancient Indo-European root. Plants of the World

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Barbeya oleoides, female flower, Saudi Arabia (TM) [180]

EUDICOTS

Barbeya oleoides, male flowers, Barbeya oleoides in fruit, Saudi Saudi Arabia (TM) [180] Arabia (TM) [180]

180. BARBEYACEAE Elm-olive family

With greyish opposite lanceolate leaves, it has a superficial resemblance to the cultivated olive (Olea europaea, Oleaceae), but it is not related. The flowers are wind-pollinated. Genera and species: This family includes the single species, Barbeya oleoides.

These are unisexual trees with opposite petiolate leaves without stipules. Blades are oblong-lanceolate and white-hairy below. The unisexual flowers are actinomorphic and have three to four nearly free tepals. Male flowers have six to 12 stamens with short free filaments and basifixed anthers that open lengthwise. Female flowers have a superior ovary that is sometimes shortly stalked and is composed of a single carpel or of two or three fused carpels. The apical style is simple with a linear papillate stigma. Fruits are dry nutlets enclosed in the persistent tepals. Distribution: The family is found in dry forested slopes on both sides of the Gulf of Aden in Yemen, Somalia, Eritrea and Ethiopia. Phylogeny and evolution: In the past, the single genus Barbeya was placed in Urticales due to similarities with Ulmaceae, but molecular evidence placed it close to Dirachmaceae.

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Etymology: Barbeya is named for Swiss botanist and politician Wiliam Barbey (1842– 1914). He botanised in the Mediterranean region and was founder of the journal Bulletin de l’Herbier Boissier.

181. DIRACHMACEAE Rachman family

Dirachma socotrana, illustration based on herbarium specimens [181]

hypanthium, together with the same number of free, white petals that bear appendages at the base inside the flower. Stamens are the same number as petals and basally fused to them. Anthers are basifixed and open by lengthwise slits. The semi-inferior ovary has as many locules as sepals and is densely hairy and radially lobed. The style is glabrous at the top and has a club-shaped to cylindrical stigma. The fruit is a septicidal capsule with long hairs inside and smooth seeds. Distribution: This family is restricted to Somalia and the island of Socotra, where it often grows on limestone soil. Both species are rare and highly endangered. Phylogeny and evolution: The placement of Dirachma has been considered puzzling on morphological grounds; Malvaceae, Flacourtiaceae (Samydaceae) and Geraniaceae have previously been proposed as related. Molecular phylogenetics placed Dirachma as sister to the similarly puzzling Barbeya in Rosales, each in their own family.

This is a family of shrubs and trees with simple, glandular-peltate hairs. They have simple, alternate, petiolate leaves with lineartriangular stipules. Blades have serrate to lobed margins, and venation is pinnate. The bisexual, actinomorphic flowers are borne singly in the leaf axils on a bracteate pedicel. The five, six or eight sepals are free, but placed on a

Genera and species: The single genus Dirachma contains two species: D. socotrana and D. somalensis. Etymology: Dirachma is possibly derived from rachman, a Socotran vernacular name for this scented shrub, although no derivation was given when the genus was described.

ROSALES

EUDICOTS

basal part of the hypanthium and therefore seemingly inferior, with a single locule. The single style terminates the ovary, and the stigma is on one side of the style. Fruits are achenes that are enveloped by the persistent hypanthium, which becomes fleshy or mealy and often has a hard inner layer, resembling a drupe or berry with a single seed.

182. ELAEAGNACEAE Oleaster family

These are deciduous and evergreen shrubs and small trees that are sometimes laxly climbing and usually have nitrogen-fixing root nodules. Most parts of these plants have distinctive silvery or coppery peltate scales and/or stellate hairs, and branches are sometimes spine-tipped. The petiolate simple leaves are alternate or opposite (rarely whorled) and lack stipules. Blades have entire margins and are densely covered in peltate hairs below with pinnate venation. Inflorescences are small racemes or fascicles, or the flowers are solitary in the leaf axils. The actinomorphic flowers are usually bisexual, sometimes unisexual and then the plants are dioecious. The hypanthium is constricted above the ovary. Two to six (to eight) sepals are fused to the hypanthium and often petal-like, the petals being absent. Four to eight stamens are inserted in the hypanthium tube, in bisexual flowers as many as the lobes, in male flowers twice as many. Filaments are free, and anthers are dorsifixed or basifixed, opening by lengthwise slits. The ovary is superior but tightly enclosed by the

Hippophaë rhamnoides in fruit, Royal Botanic Gardens, Kew, UK [182]

Distribution: This family of temperate and Arctic North America and temperate Europe and Asia extends into tropical Malesia, Sri Lanka, the Mascarenes and northern Australia. Phylogeny and evolution: Previously this family was placed in Rhamnales, but this order is now part of an expanded Rosales. They are indeed closely related to Rhamnaceae. The oldest fossil pollen attributed to Elaeagnaceae is known from the Eocene of Central Asia. Several Oligocene and Miocene fossils from Europe and North America are known.

or oleaster (Elaeagnus angustifolia), goumi (E. multiflora) and buffaloberry (Shepherdia argentea). Several species are also grown as ornamental garden shrubs. Their roots are able to fix atmospheric nitrogen using Frankia bacteria, making it possible for plants to grow well on poor soils. Therefore some species have been used for land reclamation and soil stabilisation, and they easily naturalise, although due to their beneficial qualities they are not often considered problematic. Etymology: Elaeagnos (ελαίαγνος) is a Greek name for a type of willow tree and is in turn derived from ελώδες (helodes), growing in swamps, and αγνός (agnos), pure, in reference to the white fruits of a willow. The name was later applied to the oleaster (E. angustifolia), which superficially resembles a willow.

183. RHAMNACEAE Buckthorn family

Genera and species: This is a family of three genera and c. 50 species: Elaeagnus (c. 40), Hippophaë (5) and Shepherdia (3). Uses: Sea buckthorn (Hippophaë rhamnoides) fruits are rich in vitamin A, C and E and one of the highest valued for health foods. They have been used for centuries in Europe and Asia to make jams, jellies, juices and drinks. Fruits of most other species are edible, although often astringent. Other species that are sometimes eaten are Russian olive

Elaeagnus umbellata, Royal Botanic Gardens, Kew, UK [182]

A family of deciduous (mostly) and evergreen trees and shrubs, they are rarely herbs (Crumenaria) or climbers, sometimes twining or tendrillate. Stems are sometimes spiny, or

Shepherdia canadensis, Helsinki Botanical Garden, Finland [182]

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ROSALES

EUDICOTS

Colletia armata, Royal Botanic Gardens, Kew, UK [183]

Zizyphus jujuba, Bucharest Botanical Garden, Romania [183]

Alphitonia neocaledonica, New Caledonia [183]

Rhamnus alaternus in fruit, Sicily, Italy [183]

short branches can be spine-tipped. Leaves are simple, usually alternate, sometimes opposite, and stipules are usually free, sometimes fused across the petiole or between petioles or transformed into spines, absent in most Phylica species. Tendrils are circinnate when present. Inflorescences are usually axillary cymes, sometimes compound panicles or reduced to fascicles or single flowers. The bisexual or unisexual flowers are actinomorphic and often small (< 6 mm). A hypanthium is usually present, cup-shaped or tubular. The four or five sepals are fused with the hypanthium rim. The four or five free petals are inserted in the mouth of the hypanthium, usually smaller than the sepals and sometimes absent, often forming a hood over the stamens. The four

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Ceanothus cyaneus, Rancho Santa Ana, California, USA [183]

Phylica pubescens, Adelaide Botanic Garden, South Australia [183]

or five stamens have thin filaments fused to the base of the petals with small anthers that open by lengthwise slits. A fleshy disc is usually present between the stamens on the hypanthium. The superior to inferior ovary is bi- to tetra-loculate and tipped with a shortly lobed style. Fruits are usually drupes, sometimes capsules with wings. Distribution: The family has a nearly cosmopolitan distribution, but is absent from the great deserts and boreal zones. Phylogeny and evolution: Because rhamnaceous pollen is known from c. 90 million-year-old deposits, the assumption can be made that the family was already

cosmopolitan before the continents were widely separated, which may explain some of the wide geographical disjunctions in some clades. The existence of Phylica species on several volcanic islands of different ages in the Atlantic and Indian Oceans allowed the radiation in this group to be dated using one of the early well-documented examples of a calibrated molecular clock. It also shows that long-distance dispersal is not uncommon in this family. Genera and species: Rhamnaceae include 55 genera and c. 1,040 species: Adolphia (1), Alphitonia (c. 13), Alvimiantha (1), Ampelozizyphus (1), Auerodendron (7), Bathiorhamnus (2), Berchemia (c. 20), Berchemiella (2),

ROSALES

EUDICOTS

Blackallia (1), Ceanothus (55), Colletia (5), Colubrina (33), Condalia (18), Crumenaria (6), Cryptandra (c. 55), Dallachya (1), Discaria (6), Doerpfeldia (1), Emmenosperma (3), Gouania (c. 50), Granitites (1), Helinus (5), Hovenia (7), Jaffrea (2), Karwinskia (16), Kentrothamnus (1), Krugiodendron (2), Lasiodiscus (7), Maesopsis (1), Nesiota (1, extinct), Noltea (1), Paliurus (5), Phylica (188), Pleuranthodes (2), Pomaderris (c. 75), Pseudoziziphus (2), Reissekia (1), Retanilla (4), Reynosia (c. 15), Rhamnella (10), Rhamnidium (12), Rhamnus (c. 120), Sageretia (35), Sarcomphalus (32), Schistocarpaea (1), Scutia (4), Siegfriedia (1), Smythea (10), Spyridium (45), Stenanthemum (c. 35), Trevoa (1), Trichocephalus (1), Trymalium (13), Ventilago (c. 40) and Ziziphus (c. 66). Uses: Several species produce edible fruit. Chinese jujube or zǎo (Ziziphus jujuba) and Indian jujube or ber (Z. mauritiana) are grown commercially and usually sold dried, resembling dates. Ziziphus lotus is the lotus fruit of the ancients, eaten by the ‘lotophagi’ mentioned in the Odyssey and ‘sidr’ (‫ةردس‬ ‫ )هتنملا‬or lote-tree of the Quran. Other species of Ziziphus, Condalia, Reynosia and Sageretia and Karwinskia humboldtiana also have edible fruits. Mistol fruits (Ziziphus mistol) are brewed into an alcoholic drink in the Andes. The raisin tree (Hovenia dulcis) has swollen fruit stalks that turn red after frost and are edible. Leaves of Chinese sweet plum (Sageretia thea) are used as a tea in Vietnam. Ventilago calyculata seeds can be pressed for cooking oil. Several species have saponins; leaves of the Australian soap tree (Alphitonia

Ulmus laevis fruits, Turku, Finland [184]

excelsa) are used as a soap substitute, and some Gouania species are an alternative to commercial shampoo. Ampelozizyphus, Colletia and Colubrina also yield soap. Dyes are also common in this family. Several Rhamnus species yield yellow or green dyes, traditionally used in Europe and East Asia. Ventilago madraspatana bark yields a red dye, and kauila (Alphitonia ponderosa) bark yields a bluish dye. Wood of the latter was also used for carving and weapons in Hawaii. Some species have extremely hard and heavy wood. Others produce fine timber for construction, woodworking etc. Charcoal of alder buckthorn (Rhamnus frangula) was traditionally used when making gunpowder. Ziziphus spinacristi is one of the contenders for the tree from which Jesus’ crown of thorns could have been made. The shoots of the rattan vine (Berchemia scandens) are sometimes used for wicker work in the United States, and several species of Ceanothus, Colletia, Noltea and Pomaderris are grown as ornamental garden shrubs. Phylica arborea (Tristan da Cunha and Amsterdam Island) is the only woody native species on Tristan da Cunha (South Atlantic Ocean) and the other islands in the Archipelago, and it is known as the island tree and has been used for firewood etc. Its dispersal between the islands in the archipelago and to Ile Amsterdam (southern Indian Ocean) represent amazing repeated inter-island dispersals, the more so because the seeds do not survive in sea water. Etymology: Rhamnos (ραμνος) is the Greek name for a prickly shrub, such as a buckthorn.

184. ULMACEAE Elm family

These trees and shrubs have watery sap and alternate and opposite leaves that are arranged in a plane along the stem (distichous). Stipules grow in pairs on either side of the petioles, and leaf blades are simple, strongly serrate and basally asymmetrical. Venation is pinnate and, in all but Ampelocera, secondary veins terminate in teeth. Inflorescences are axillary cymes or fasciculate aggregates of flowers in the leaf axils. The unisexual or bisexual flowers are green or brown, the perianth spirally arranged with (two to) four to eight (or nine) fused or free tepals. Stamens are the same number as the tepals (rarely more) with dorsifixed, often versatile anthers that open by lengthwise slits. The superior ovary is composed of two fused carpels forming a unilocular pistil topped with two linear styles that can be simple or bifurcate and a stigma on the inner surface. Fruits are flattened nuts, drupes or samaras. Distribution: Ulmaceae are primarily found in temperate areas in the Northern Hemisphere, but species extend into the

Ulmus laciniata, Helsinki Botanical Garden, Finland [184]

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ROSALES American and African tropics and subtropical East Asia to Sumatra, Sulawesi and the Sunda Islands. Phylogeny and evolution: Fossilised fruits and leaves of Ulmus are known from 50 million-year-old Eocene deposits in northeastern China, suggesting a greater age of the family than initially assumed. The family has two clades, one predominantly tropical and the other mostly temperate. Some genera of the former subfamily Celtidoideae are now part of Cannabaceae. Genera and species: Ulmaceae include seven genera and c. 45 species: Ampelocera (10), Chaetachme (1), Hemiptelea (1), Phyllostylon (2), Planera (1), Ulmus (c. 25) and Zelkova (4). Uses: Elm wood (Ulmus spp.) is rot-resistant and therefore was often used in waterworks, wells, coffins etc. Due to Dutch elm disease (caused by the Asian fungus Ophiostoma ulmi, dispersed by the elm bark beetle Scolytus multistriatus), large plantations are not viable, and elm trees have largely disappeared from the landscape and as street trees in Europe and North America in the latter part of the 20th century. Resistant strains have, however, now been found but are much more expensive to propagate. Keaki (Zelkova

EUDICOTS

serrata) is also cultivated for ornament and wood. The wood of Chaetachme aristata is sometimes made into musical instruments, and the fine-grained wood of baitoa (Phyllostylon brasiliensis) is sometimes used for turning. Etymology: Ulmus is the classical Latin name for an elm tree. It originated from the Akkadian u’ulum, to bind, or from ProtoIndo-European el, brown.

185. CANNABACEAE Hemp family

This is a family of trees, shrubs, perennial and annual herbs and vines with watery sap. Plants are unisexual, bisexual or polygamous. The petiolate leaves are alternate or opposite, usually in two ranks, simple, deeply lobed or palmately compound with paired stipules. Venation is palmately pinnate. The terminal

or axillary inflorescences are cymes, panicles or fascicles, or sometimes the flowers solitary. The brown or green bisexual or unisexual actinomorphic flowers usually have four to eight (sometimes fewer or more) fused tepals. Stamens are usually as many as tepal lobes. Anthers are basifixed or dorsifixed and open by lengthwise slits. The superior ovary is composed of two fused carpels topped with two linear, simple or bifurcating styles with the stigmatic area along their inner surfaces. Fruits are nuts, drupes, achenes and samaras. Distribution: This worldwide family is found throughout the Americas, Europe and North Africa, Sub-Saharan Africa, Madagascar, Yemen, Turkey, Caucasus, Central Asia throughout tropical Asia, Australia and Pacific islands. Phylogeny and evolution: Cannabaceae have always been associated with Moraceae and Urticaceae, with which they share many characters. Molecular results have shown that Ulmaceae in the wider sense (based on an interpretation of their morphology) were polyphyletic, resulting in several former genera of Ulmaceae (mainly from subfamily Celtidoideae) being placed here. The oldest fossil Cannabaceae are known from Tertiary deposits.

Cannabis sativa, legal medicinal marijuana plantation in Portland, Humulus lupulus, male, Canbury Gardens, Humulus lupulus, female, Canbury Oregon, USA (DH) [185] Kingston upon Thames, UK [185] Gardens, Kingston upon Thames, UK [185]

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Lozanella enantiophylla, San Francisco Botanical Garden, USA [185]

ROSALES

EUDICOTS

Genera and species: Cannabaceae include 9 genera and c. 100 species: Aphananthe (3), Cannabis (1), Celtis (c. 60), Gironniera (6), Humulus (3), Lozanella (2), Parasponia (5), Pteroceltis (1) and Trema (c. 15). Uses: Use of cannabis (Cannabis sativa and its many varieties) as a recreational drug, due to the psychoactive resin tetrahydrocannabinol (THC), can be dated back to at least 440 BC. Herodotus, for example, mentioned its use: ‘The Scythians ... take some of this hempseed and ... throw it upon the red-hot stones; immediately it smokes and gives out such a vapour as no Grecian steam-bath can exceed. The Scyths delightedly shouted for joy.’ However, hemp has been cultivated for 8,500 years for its fibre, used in fabric and rope, and oil in its seeds, for food, varnish, soap and fuel, although because of legislative restrictions it is much less frequently cultivated for these purposes nowadays. Cannabis is currently the largest cash crop in the United States, although mostly grown illegally. Nevertheless, legalisation of cannabis is progressing (several countries and states have now legalised the drug) and this has proven to help lift the cultivation, trade and use of mild drugs out of the criminal circuit. Taxes collected from this trade can then be used to alleviate addictions to this and more damaging addictive “soft” drugs (like sugar, alcohol and tobacco). Hops (Humulus lupulus) were already used to flavour beer in Europe in the 8th century, gradually replacing the use of other plants such as bog myrtle (Myrica gale, Myricaceae); hops have been in cultivation since the 1200s. Hops contain lupulin, a pseudo-oestrogen causing the infamous beer belly. The young shoots of hops were Silk moth caterpillars eating mulberry (Morus alba) leaves, market in Shanghai, China [186]

harvested and eaten like asparagus since Roman times, and this is still done in Mediterranean cuisine. Celtis produces strong wood (e.g. beaver wood) that is used for furniture, and the rough leaves of Aphananthe aspera can be used as sand paper. Quickly growing guacimilla (Trema micrantha) was used for pre-Columbian bark cloth and is now harvested for export and tourism. Etymology: Cannabis is a Latinised form of the Greek name of the plant, κάνναβης (kannabis), which originally came from Scythian into Greek. It is possibly a compound of a Fenno-Ugric word for hemp, kene, and the Proto-Germanic pish, to burn. Its IndoEuropean roots (qunabu, hanapiz) may be the source of the English words canvas and hemp.

186. MORACEAE Mulberry family

leaving a scar on the stem when dehiscing. Inflorescences are bisexual or unisexual axillary racemes or cymes, often fused into heads or cup- or urn-shaped structures with the flowers on the inside, sometimes subtended by bracts; flowers sometimes solitary. The unisexual flowers have a simple perianth with usually four (sometimes up to ten) fused tepals or perianth absent. Male flowers have (one to) four (to six) stamens with straight or curved, free or fused filaments. Anthers open explosively when the stamens are curved outward, or the anthers are fused into peltate structures with a circumscissile opening. Pistillodes are often present in male flowers. Female flowers are without staminodes, the superior or inferior ovary is topped with one or two styles and stigmas. The fruit is a drupe, rarely a dry achene, usually enveloped in a fleshy perianth and often immersed in the flashy receptacle, sometimes the inflorescence fused (e.g. a syncarp in Artocarpus, Ficus). Distribution: This widespread family occurs worldwide, but is absent from northern and northwestern North America, northern Eurasia, the Sahara, southern Australia, New Zealand and Antarctica.

These are terrestrial and epiphytic trees, shrubs, climbers and perennial herbs, usually with milky sap. The usually alternate (rarely opposite or whorled) leaves are simple, sometimes palmately or pinnately compound, and blades are entire, toothed or deeply pinnately or palmately lobed; venation is pinnate, palmate or three-veined. Stipules are usually present and fused around the bud,

Phylogeny and evolution: Moraceae are closely related to Urticaceae, and indeed some genera such as Cecropia have been moved between the two families. Together with Cannabaceae and Ulmaceae, they form the ‘urticalean’ clade in Rosales. The heterogeneous genus Ficus has diversified together with its specialised pollinator, the fig wasp (superfamily Chalcidoidea), with many fig species having specialised wasps only found in association with their host.

Dorstenia christenhuszii, Royal Botanic Gardens, Kew, UK [186]

Broussonetia papyrifera, Royal Botanic Gardens, Kew, UK [186]

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ROSALES

Artocarpus altilis, Moorea, French Polynesia [186]

Ficus austrocaledonicus, New Caledonia [186]

Ficus benghalensis, a strangler fig, Tahiti, French Polynesia [186]

Genera and species: Moraceae include 37 genera and c. 1,180 species: Antiaris (1), Antiaropsis (2), Artocarpus (45), Bagassa (1), Batocarpus (3), Bleekrodea (3), Bosqueiopsis (1), Brosimum (15), Broussonetia (8), Castilla (3), Clarisia (3), Dorstenia (107), Fatoua (2), Ficus (c. 850), Helianthostylis (2), Helicostylis (7), Hullettia (2), Maclura (11), Maquira (4), Mesogyne (1), Milicia (2), Morus (13), Naucleopsis (22), Parartocarpus (2), Perebea (9), Poulsenia (2), Prainea (2), Pseudolmedia (9), Scyphosyce (2), Sorocea (14), Sparattosyce (2), Streblus (14), Treculia (3), Trilepisium (1), Trophis (9), Trymatococcus (2) and Utsetela (2).

Captain William Bligh was sent on the H.M.S. Bounty to bring plants from Tahiti to Jamaica to establish a plantation there. Crew members married Tahitian women and were upset when they were forced to sail for the West Indies, resulting in the infamous mutiny on the Bounty. Captain Bligh managed to get to Indonesia in a longboat, whereas the mutineers retrieved their wives from Tahiti and settled on Pitcairn Island. On a second voyage, the breadfruit finally made it to the West Indies, where the slaves refused to eat the fruit. It is still commonly cultivated in Jamaica. The related jackfruit, Artocarpus heterophyllus, is commonly cultivated around the tropics, and the sweet pulp is sometimes canned. Chempedak (A. integer) is used like breadfruit in Malaysia. Seeds of breadnut (Brosimum alicastrum) are eaten in tropical America, and elephants distribute African breadfruit (Treculia africana), which has large seeds that are eaten locally by people. Mulberries are also commonly grown for their fruit, especially southern mulberry (Morus australis) and black mulberry (M. nigra), both cultivated for millennia. Broussonetia luzonica inflorescences are used in Philippine cuisine. Fruit of Clarisia is also eaten, and the fruit of Maclura tricuspidata is valued in China and Korea. Delicate paper is prepared from the paper mulberry, B. papyrifera, in East Asia, and the fibre is used to make cloth in many Pacific islands. Kozo, B. kazinoki, is used in Japan for paper making, often erroneously called ‘rice paper’. Its fruits and leaves can be eaten after cooking. The white mulberry (Morus alba), which also has edible fruit, is the foodplant for farmed caterpillars of the silk moth (Bombyx mori), and the bark of this

species was used to make paper money during the Ming Dynasty in China. Many species yield valuable timber, especially ipoh (Antiaris toxicaria), jak (Artocarpus heterophyllus), letterwood (Brosimum guianense), satiné (B. rubescens), iroko (Milicia excelsa) and osage orange (Maclura pomifera). Ulé rubber (Castilla elastica) and the rubber fig (Ficus elastica) were formerly important rubber sources. Buddha had his true insights beneath a peepul tree, Ficus religiosa, which is now sacred to Buddhists and Hindus, and its leaves are used for miniature paintings. Bark of Helicostylis is hallucinogenic and used for witchcraft in the Guianas. The motile stamens and tepals of Morus alba move at half the speed of sound, releasing the pollen in the wind, being the most quickly moving parts of any plant. Many species are cultivated as ornamentals, especially Ficus benjamina, which is the most common leafy houseplant. Many species of figs are planted as shade trees in the tropics. The oldest known planted tree is a sacred fig (Ficus religiosa) in Sri Lanka, called Jaya Sri Maha Bodhi, which was planted in 288 BC. Several Dorstenia species are grown in specialist collections for their intriguing inflorescences, resembling figs turned inside out.

Uses: The common fig, Ficus carica, is frequently grown as a fruit tree. It was probably already cultivated in pre-pottery Neolithic times in the Levant, c. 11,300 years ago. It naturalised early around the Mediterranean, where it commonly grows on old masonry and in archaeological sites. The sycamore of the Bible, or mulberry fig, Ficus sycomorus, had been domesticated for its fruit in Ancient Egypt (and is believed to be the sycamore that Zacchaeus climbed to get a better view of Jesus, as reported in the New Testament). Figs are now cultivated in many parts of the world, and in the tropics the fruits of many other Ficus species are also eaten, sometimes on a commercial scale. The common breadfruit, Artocarpus altilis, is an important food source in tropical Asia and the Pacific. The value of the fruit in the Pacific was first observed by Captain James Cook in Tahiti in 1769, and in England it was thought to be a useful crop for feeding slaves in the British colonies in the West Indies. 274

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Etymology: Morus is the Latin name for the black mulberry tree, M. nigra. It is derived from Ancient Greek μορον (moron), a mulberry (Morus) or blackberry (Rubus, Rosaceae). The Spanish mora is used for both fruits and can cause confusion where both kinds of fruit occur.

ROSALES

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187. URTICACEAE Nettle family

This family includes terrestrial and epiphytic, bisexual and unisexual, annual and perennial herbs, shrubs, lianas and trees, sometimes with arial and stilt roots. Opposite or alternate, spirally arranged leaves have free and lateral or interpetiolar and fused, often amplexicaul, stipules that fall when the leaf develops. Blades are simple or pinnately or palmately lobed, the margins entire and venation pinnate or palmate. Petioles can be basally or centrally attached and then the blade peltate, or the petiole absent and the blade sessile. Stinging hairs are present in some species. Inflorescences are often

Obetia ficifolia, Réunion [187]

Cecropia hispidissima, Ecuador [187]

unisexual in pairs in the leaf axils and can be cymes, racemes, heads, false umbels or spikes, clustered and sometimes subtended by a bract. The unisexual, rarely bisexual, f lowers are actinomorphic or (especially female flowers) zygomorphic. Male flowers have (one or) two to five free or fused tepals and one to five stamens, the filaments curved, but suddenly reflexing and ejecting pollen. Anthers are basifixed and open by lengthwise slits. Female flowers have two to five tepals that are free or fused into a tube, often unequal, rarely absent, and staminodes are sometimes present and can be scalelike, often important for fruit dispersal. The superior ovary is composed of a single carpel and topped with a single variably shaped sessile or stalked stigma. Fruits are achenes that are usually free, sometimes fused with a fleshy perianth that develops at fruit maturity. Distribution: The family has a global distribution apart from dry or permafrost areas. They are most numerous in the wet tropics but can also be common in temperate regions.

Pilea microphylla, Guadeloupe [187]

Urtica dioica, near Turku, Finland [187]

Phylogeny and evolution: Fossil leaves of Urticaceae have been reported from Upper Cretaceous deposits, and a stamen and tepal of a putative member of Urticaceae have been found in Eocene Baltic amber. Cecropiaceae have traditionally been associated with Moraceae or placed in that family in the past on the basis of the female structures, but they were already included on morphological grounds in Urticaceae in the 1960s. Cecropiaceae were considered a morphological link between Urticaceae and Moraceae, but molecular studies have placed Cecropia and its relatives in Urticaceae. The latter are polyphyletic if Cecropiaceae are excluded. Genera and species: Urticaceae include 53 genera and c. 1,250 species: Aboriella (1), Archiboehmeria (1), Astrothalamus (1), Australina (1), Boehmeria (c. 80), Cecropia (c. 75), Chamabaina (2), Coussapoa (50), Cypholophus (15), Debregeasia (4), Dendrocnide (37), Didymodoxa (2), Discocnide (1), Droguetia (7), Elatostema (c. 300), Forsskaolea (6), Gesnouinia (2), Forsskaolea angustifolia, Bergius Botanical Garden, Stockholm, Sweden [187]

Laportea canadensis, Wisconsin, USA [187]

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ROSALES Gibbsia (2), Girardinia (2), Gonostegia (5), Gyrotaenia (6), Hemistylus (4), Hesperocnide (2), Laportea (21), Lecanthus (1), Leucosyke (35), Maoutia (15), Meniscogyne (2), Musanga (2), Myrianthus (7), Myriocarpa (18), Nanocnide (2), Neodistemon (1), Neraudia (5), Nothocnide (5), Obetia (8), Oreocnide (15), Parietaria (c. 10), Petelotiella (1), Phenax (12), Pilea (c. 200), Pipturus (30), Poikilospermum (20), Pourouma (25), Pouzolzia (70), Procris (16), Rousselia (3), Sarcochlamys (1), Sarcopilea (1), Soleirolia (1), Touchardia (1), Urera (35) and Urtica (80). Uses: The boiled young shoots of Girardinia, Laportea and Urtica are eaten as vegetables and in soup. Common nettle (Urtica dioica) is used as flavouring in Dutch nettle cheese, and Cornish yarg cheese is traditionally wrapped in these leaves. Several species are cultivated for their stem fibre, which is of high quality and used to make cloth, fishing

EUDICOTS

nets and ropes. For instance fibre of U. dioica was used to make khaki cloth for military uniforms, notably in the Second World War. Ramie (Boehmeria nivea) is widely cultivated in East Asia and is the toughest, longest and silkiest of all vegetable fibres. Similarly fibre is collected from Girardinia diversifolia subsp. triloba, Sarcochlamys pulcherrima, Urtica dioica and many other species. Orange wild rhea, Debregeasia longifolia, also has good fibre, and its edible fruit is known as janatsi or yanagi. Fruits of uvilla, Pourouma cecropiifolia, taste like grapes. Tubers of Pouzolzia tuberosa are eaten in tropical Asia. The fruit of corkwood, Myrianthus arboreus, is eaten in Africa, and its wood is lighter than cork. Several species of Pilea and Soleirolia soleirolii are widely cultivated as ornamentals.

stinging hair breaks off upon contact, leaving a sharp point that readily pierces skin and allows the irritating liquid inside the hair to enter flesh. The hollow hairs act like a miniature hypodermic needle. Despite the painful result, nettles (Urtica dioica) were pulled out using bare hands into the 20th century, in the belief that the resulting inflammation was a useful treatment against arthritis and rheumatism. As quickly growing pioneer trees in the Neotropics, Cecropia attracts fire ants with glycogen-rich food bodies (Mullerian bodies) at the base of their petioles. The ants enter the plant there and make the hollow stems their home, which of course they defend against intruders. Even though these species do not have stinging hairs, this is another one to handle with care.

Do not touch this nettle: Stinging hairs in Urticaceae have a distinct bulbous or cylindric base and a stiff, translucent apex. The tip of the

Etymology: Urtica is the Latin name for nettle, first used by Plinius. It probably originated from Latin urere, to sting or burn.

FAGALES Families 188 to 195 make up Fagales. An order with this name has been included in many morphology-based classifications, often associated with other sets of wind-pollinated families in the so-called higher Hamamelidae. In that circumscription, Hamamelidae were, however, grossly polyphyletic. In modern molecular-based classifications, Fagaceae and their relatives are associated with other families in which nitrogen-fixation via root nodules occurs. The order is then associated with Curcurbitales, a mostly animal-pollinated order. There are fossils that exhibit morphological traits that are mixtures of those typical of these two orders.

188. NOTHOFAGACEAE Roble family

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Nothofagus antarctica, female branch, Royal Botanic Gardens, Kew, UK [188]

Nothofagus obliqua, male flowers, Royal Botanic Gardens, Kew, UK [188]

FAGALES

EUDICOTS

This is a family of evergreen and deciduous, bisexual trees and shrubs. The alternate leaves are usually in two ranks (distichous) or spirally arranged, and stipules are attached basally or peltate. Blades are simple, entire, serrate to doubly serrate, and the lamina is covered with globular-glandular hairs. Inflorescences are one- to three-flowered dichasia, up to seven (rarely up to 15) in female inflorescences. Male flowers are sessile or shortly stalked and have a fused, regularly splitting perianth composed of four to six fused tepals. The four to 90 stamens per flower have long, flexible filaments and basifixed anthers with a protruding connective. Female flowers are sessile or shortly stalked with a persistent involucre; they often have staminodes. The inferior ovary is tipped with short styles and usually curved stigmas. Fruits are two- or three-angled nuts surrounded by a one- to four-valved cupule with lamellar appendages. Distribution: This family can be found in southern South America, New Guinea, New Caledonia, eastern and southern Australia (New South Wales, Victoria, Tasmania) and New Zealand. Lithocarpus variolosus, Royal Botanic Gardens, Kew, UK [189]

Phylogeny and evolution: Nothofagus was previously included in Fagaceae, but it was found to be sister to all other Fagales in molecular studies. Therefore they have been placed in their own family. This family had a wider distribution during the Cretaceous and Tertiary in the Southern Hemisphere, and fossils are known from Australia, New Zealand, Antarctica, South America and the Falkland Islands. It was suggested that the current distribution is the result of continental drift, but modern clades evolved after the breakup of Gondwana. It is therefore more likely that the family reached this distribution via long-distance dispersal; for instance they reached New Zealand by long-distance dispersal c. 30 million years ago. Genera and species: The sole genus is Nothofagus with 43 species. The genus has been subdivided into subgenera (sometimes accepted as genera): Fuscospora (6), Lophozonia (7), Nothofagus (5) and Trisyngyne (25), but these are not widely accepted as genera. Nothofagus in the broad sense is monophyletic, and the advantages of splitting it are unclear, making this subdivision not strictly necessary.

Quercus crassifolia, Royal Botanic Gardens, Kew, UK [189]

Uses: Timber of southern beech or roble, Nothofagus, is hard and strong with a close grain and is valued especially for cabinetry and turning. It is also locally used for general construction and railway sleepers. Etymology: Nothofagus is composed of the Greek νόθος (nothos), false, and Latin fagus, a beech tree.

189. FAGACEAE Beech family

These trees (rarely shrubs) are bisexual and deciduous or evergreen. Simple leaves are usually alternate, rarely in whorls of three (Trigonobalanus), and have entire, serrate, sinuate or lobed blades with pinnate venation; they are often covered with branched or

Fagus sylvatica, Royal Botanic Gardens, Kew, UK [189]

Fagus sylvatica, Bix Bottom, UK [189]

Quercus ilex, Mt Saint-Victoire, France [189]

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FAGALES stellate hairs. Stipules are free and deciduous. Inflorescences are usually reduced spikes, heads or cymules, sometimes with solitary flowers in the leaf axils and male flowers sometimes in pendent catkins. The unisexual flowers are actinomorphic and have a usually six-, sometimes four- to nine-lobed perianth. Male flowers have usually 12, sometimes four to 20, stamens with free, filiform filaments and linear to kidney-shaped, dorsifixed or basifixed anthers opening by lengthwise slits. A pistillode is sometimes present among the stamens. Female flowers are surrounded by a cupule, the perianth usually six-lobed, but it is sometimes poorly developed. Staminodes can be absent, but when they are present there are six to 12 surrounding the ovary. The superior ovary is two- to six-loculed and has as many short styles on the top as there are locules, the stigmas capitate or linear and covering the inside of the styles. The fruit is a one- to threecelled nut that can be round, three-angled or winged, but always attached to a sessile or stalked cupule that can be saucer- or cupshaped or encloses the fruit, which can be dehiscent and variously ornate or not. Distribution: Fagaceae are distributed across the temperate zones of the Northern Hemisphere, extending into the tropics in Central America and northwestern South America, Cuba, tropical Asia and New Guinea. Phylogeny and evolution: Fossil beechwood (Fagoxylon) is known from Upper Cretaceous deposits across the Northern Hemisphere. The family was more diverse in the Tertiary. The crown group has been estimated to be c. 34–37 million years old. They are sometimes divided into two subfamilies: Fagoideae including Fagus only, and Quercoideae encompassing the rest. Genera and species: Fagaceae have eight genera with 927 species: Castanea (8), Castanopsis (136), Chrysolepis (2), Fagus (10), Lithocarpus (336), Notholithocarpus (1), Quercus (431) and Trigonobalanus (3). Uses: Sweet chestnuts, Castanea sativa, have been cultivated since Roman times and

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were staple food for Roman soldiers, which caused the species to be introduced from the Mediterranean to all of Europe. It is still cultivated for its edible seeds, although mostly they are grown in Asia and then are often the Chinese chestnut (C. mollissima), which has been cultivated there, also for thousands of years. The American chestnut (C. dentata), Japanese chestnut (C. crenata) and chinquapin (C. pumila) and species of Castanopsis, Chrysolepis, Fagus and Lithocarpus densiflorus also have edible seeds and are eaten locally. Ground acorns (seeds of Quercus spp.) have been eaten as a famine food in Europe and even as a substitute for instant coffee. In Spain, ham from pigs fed on acorns is considered a delicacy and commands a higher price than other ham. The thick bark of the cork oak (Quercus suber) is harvested every eight to ten years, and this is the cork of commerce, used in flooring, insulation, bottle corks, floats etc. Beechwood is highly valued for cabinetry and furniture. Oak is frequently harvested for timber, and English oak (Quercus robur) was especially important in the past for the construction of houses, ships, furniture and wine barrels, giving a particular flavour to wine, port and sherry. Semi-fossilised oak wood (due to burial in peat) is known as bog oak, and due to its extreme hardness, was the wood of choice for heavy clubs (known as a shillelagh) in Ireland. Bark of Castanopsis and Quercus is used to make dyes, and oak galls were collected to make ink. Acorns were used for tanning, but tannins are now more frequently produced in the laboratory. Many species are highly valued ornamentals and frequently planted as shade trees especially in the temperate zones. Being worshipped in Europe since ancient times, oaks have become the national symbols of Germany, Ireland and the United States. Mistletoe (Viscum album, Santalaceae) was considered more sacred by druids when it grew on oak trees than on other trees. In British folklore, the amount of rain was thought to be predicted by the sequence of leafing out in oak and ash (Fraxinus excelsior, Oleaceae). If the oak leafed out first, relatively little rain would fall, but if the ash leaves came first, it was thought to presage a wet summer.

Etymology: Fagus is the classical Latin name for a beech tree, from its Indo-European root bhehgos. It probably is a cognate with classical Greek φαγειν ( fagein), to eat, in reference to its edible nuts. The surname of one of the authors of this book (Fay) is believed to be derived from the Norman French common name for Fagus sylvatica.

190. MYRICACEAE Bayberry family

Evergreen shrubs and small trees make up this family. Plants are unisexual or bisexual and are often covered with resinous, peltate glands, making the plants aromatic. Roots frequently have nitrogen-fixing nodules. They have simple alternate leaves usually lacking stipules and nearly sessile blades. Blades are entire to irregularly serrate or lobed, pinnatifid and subtended by stipules in Comptonia. Inf lorescences are unisexual spikes, and f lowers usually lack a perianth (Canacomyrica has a sixlobed perianth) and are wind-pollinated. Male f lowers are solitary in the axils of an inf lorescence bract, and each is usually subtended by two to four bracteoles. The two to eight (rarely up to 20) stamens occur in groups at the base of the bract, progressively fewer towards the tip of the inf lorescence. Filaments are short, free or slightly fused at base, and the erect anthers open by lengthwise slits. Female f lowers are up to four per inf lorescence bract, and each f lower is subtended by two to four bracteoles. The more or less inferior ovary (superior in Comptonia) is composed of two fused carpels forming a single locule. The two styles are free or fused at the base. Fruits are drupe-like nutlets, often with wart-like, wax-covered papillae.

FAGALES

EUDICOTS

Distribution: This family is widespread across both hemispheres, occurring mostly in temperate, subtropical or tropical-montane regions. Phylogeny and evolution: Myricaceae are sister to Juglandaceae and form a well-suppor ted subclade in Fagales, an association well supported by their morphology and fossil history. Myrica is sometimes subdivided, and genera such as Gale, Faya and Morella are then accepted. They nevertheless are similar morphologically. Comptonia is closely related to Myrica and sometimes included there. The genus was widespread across the Northern Hemisphere during the Tertiary, but is now restricted to eastern North America