Handbook of Zoology / Handbuch der Zoologie. Teilband/Part 30 Planipennia: Lacewings [Reprint 2014 ed.] 9783110858815, 9783110118872

Table of contents :
Historical account
Diagnosis of order
Palaeontology and phylogeny
Systematic account
Key to families
Family Coniopterygidae
Family Rapismatidae
Family Ithonidae
Family Osmylidae
Family Sisyridae
Family Dilaridae
Family Polystoechotidae
Family Neurorthidae
Family Mantispidae
Family Berothidae
Family Hemerobiidae
Family Chrysopidae
Family Psychopsidae
Family Nymphidae
Family Myrmeleontidae
Family Ascalaphidae
Family Nemopteridae
Zoogeography and distribution
Ecology
Habitats
Feeding habits
Life histories and voltinism
Dispersal
Natural enemies
Predators
Parasites
Defences
Economic importance
Morphology, Anatomy and Physiology
Morphology Introduction
Head
Thorax
Legs
Wings
Abdomen
Female external genitalia
Male external genitalia
Anatomy
Female internal reproductive system
Male internal reproductive system
Musculature
Alimentary system
Respiratory system
Nervous system
Sense organs
Glands
Cytology
Modes of reproduction
Courtship and mating
Oviposition and fecundity
Embryonic development
Post embryonic development
Dormancy
Reproductive longevity
Eggs and hatching
Larval morphology
Head
Thorax
Abdomen
Recognition of larvae
Key to late instar larvae
Systematic synopsis
Larval anatomy
Mouthparts and feeding
The Glands
Cibarium and food pump
Gut and excretion
Respiration
Silk production
Nervous system
Pupation and adult emergence
Literature cited
Index of scientific names
General index

Citation preview

Handbuch der Zoologie Handbook of Zoology Band/Volume IV Arthropoda: Insecta Timothy R. New Planipennia (Lacewings) Teilband/Part 30

Handbuch der Zoologie Eine Naturgeschichte der Stämme des Tierreiches

Handbook of Zoology A Natural History of the Phyla of the Animal Kingdom

Gegründet von / Founded by Willy Kükenthal Fortgeführt von / Continued by M. Beier, M. Fischer, J.-G. Helmcke, D. Starck, H. Wermuth

Band/Volume IV Arthropoda: Insecta Teilband/Part 30 Herausgeber/Editor

W DE G

Maximilian Fischer

Walter de Gruyter • Berlin • New York 1989

Timothy R. New

Planipennia Lacewings

w G DE

Walter de Gruyter • Berlin • New York 1989

Autor / Author Dr. Timothy R. New Reader in Zoology La Trobe University Bundoora/Victoria Australia 3083 Tel.: (03)4783122

Herausgeber und Schriftleiter Scientific and Managing Editor

Verlag Publishers

Hofrat Univ.-Doz. Mag. Dr. Maximilian Fischer Direktor am Naturhistorischen Museum Wien Burgring 7 A-1014 Wien Austria Tel. (0222) 934541-316

Walter de Gruyter Genthiner Straße 13 D-1000 Berlin (West) 30 F.R. of Germany Tel. (030) 26005-124 Telefax (030)26005-251

Deutsche Bibliothek Cataloguing in Publication

Walter de Gruyter, Inc. Scientific Publishers 200 Saw Mill River Road Hawthorne, N.Y. 10532 USA Tel. (914) 747-0110 Telefax (914)747-1326

Data

Handbuch der Zoologie : eine Naturgeschichte der Stämme des Tierreiches = Handbook of zoology / gegr. von Willy Kükenthal. Fortgef. von M. Beier . . . - Berlin ; New York : de Gruyter. NE: Kükenthal, Willy [Begr.]; Beier, Max [Hrsg.]; PT Bd. 4. Arthropoda: Insecta / Hrsg. Maximilian Fischer. Teilbd. 30. Planipennia : lacewings / Timothy R. New. - 1989 ISBN 3-11-011887-4 (Berlin) ISBN 0-89925-539-6 (New York) NE: Fischer, Maximilian [Hrsg.]; New, Timothy R. [Mitverf.]

Printed on acid free paper Copyright © 1989 by Walter de Gruyter & Co., Berlin. All rights reserved, including those of translation into foreign languages. No part of this book may be reproduced in any form - by photoprint, microfilm, or any other means - nor transmitted nor translated into a machine language without written permission from the publisher. Printed in Germany. Typesetting and Printing: Tutte Druckerei G m b H , Salzweg-Passau. Binding: Luderitz & Bauer G m b H Berlin.

Contents

Historical account Diagnosis of order Palaeontology and phylogeny Systematic account Key to families Family Coniopterygidae Family Rapismatidae Family Ithonidae Family Osmylidae Family Sisyridae Family Dilaridae Family Polystoechotidae Family Neurorthidae Family Mantispidae Family Berothidae Family Hemerobiidae Family Chrysopidae Family Psychopsidae Family Nymphidae Family Myrmeleontidae Family Ascalaphidae Family Nemopteridae Zoogeography and distribution Ecology Habitats Feeding habits Life histories and voltinism Dispersal Natural enemies Predators Parasites Defences Economic importance Morphology, Anatomy and Physiology . Morphology Introduction Head Thorax Legs Wings Abdomen Female external genitalia

1 2 2 10 10 11 13 14 16 18 19 20 21 22 23 24 25 27 30 30 35 36 38 42 42 43 47 48 49 50 50 50 51 52 52 53 55 56 58 60 63

Male external genitalia Anatomy Female internal reproductive system Male internal reproductive system Musculature Alimentary system Respiratory system Nervous system Sense organs Glands Cytology Modes of reproduction Courtship and mating Oviposition and fecundity Embryonic development Post embryonic development Dormancy Reproductive longevity Eggs and hatching Larval morphology Head Thorax Abdomen Recognition of larvae Key to late instar larvae Systematic synopsis Larval anatomy Mouthparts and feeding The Glands Cibarium and food pump Gut and excretion Respiration Silk production Nervous system Pupation and adult emergence Literature cited Index of scientific names General index

65 66 66 70 72 72 73 74 74 77 77 79 80 82 87 87 88 89 90 91 91 94 95 96 96 97 101 101 103 105 105 107 107 107 108 Ill 125 131

Planipennia (Lacewings)

Historical account The Planipennia have long been treated as part of the insect order Neuroptera, and were thus included in early much broader concepts of that order. They were allied by Linnaeus (1758) with such diverse groups as Odonata, Psocoptera, Plecoptera, Ephemeroptera, Trichoptera and Mecoptera in his 'Neuroptera' - an amalgam of groups now recognised as widely distinct orders, and including insects with incomplete and complete metamorphoses. Fabricius' (1775) major group 'Synistata' was even broader, incorporating Hymenoptera, Isoptera, Apterygota and some Crustacea with the above, but removing the Odonata. Although considerable advances in insect systematics were made during the early part of the nineteenth century, the Neuroptera was still frequently treated as a very broad array of taxa. Latreille's (1831) concept was not substantively different from the Linnaean one, and not until Brauer (1855) was a more restricted perspective commonly adopted. From then onwards, 'Neuroptera' are most commonly understood to include, at most, the Megaloptera, Raphidioptera and Planipennia, and some authorities still prefer to maintain these as a single order, with the above groups having subordinai status. Many workers now consider that each should properly be considered a distinct order, but 'Planipennia' is often then taken as a synonym of 'Neuroptera', and the latter name used. 'Planipennia' dates from Latreille (1825). Any ambiguity of delimitation is, at least, removed by referring to the insects considered here as 'Neuroptera: Planipennia', this delimiting an undoubtedly monophyletic group of neuropteroid insects - be they considered as ordinal or subordinai in status. The Neuropteroidea (Handlirsch 1908) comprises these, Megaloptera and Raphidioptera. In common with many other insect groups, work during the nineteenth century and before was concentrated in Europe, and relatively few workers have studied Planipennia at any one time. A number of pioneering syntheses are parts of broader entomological works by such eminent entomologists as Scopoli, Olivier, Curtis and Stephens, and a large number of descriptions and some faunal accounts date from around the middle of the century. Rambur's (1842) book is a significant advance from most earlier studies, including some generic keys, naming such well-known genera as Micromus (Hemerobiidae), Palpares and Acanthaclisis (Myrmeleontidae), and others, and providing descriptive and diagnostic notes for some 158 species. As with other contemporary authors, Rambur included Chrysopa s. 1. in Hemerobius. Schneider's (1851) Symbolae ad Monographium Generis Chrysopae is a landmark of lasting scientific and aesthetic value. Walker's (1853) 'List' was revised by McLachlan (1867). Descriptions of early stages were initiated over the same period: Westwood (1842) recognised the interdependence of Sisyra and freshwater sponges, and Brauer (1850-1854) outlined the biology of representatives of Chrysopidae, Ascalaphidae and Osmylidae, followed (1869) by a treatment of the complex life history of Mantispa and (1876) a major overview of the Neuroptera of Europe. Hagen, amongst numerous smaller works, produced a comprehensive Synopsis of North American taxa (1861) and a detailed systematic account of much of the order (1866). Descriptions of myrmeleontid larvae by Redtenbacher (1884) and numerous descriptive papers (dealing with Planipennia from many parts of the world) by McLachlan are amongst other significant contributions from the nineteenth century.

During the first part of the twentieth century, monographs of several families appeared - Coniopterygidae (Enderlein 1906), Ascalaphidae (van der Weele 1909), Dilaridae (Naväs 1909), Berothidae (Naväs 1929), Osmylidae (Krüger 1912-1915), Psychopsidae (Naväs 1916, Tillyard 1919), for examples. L. Naväs remains the most prolific author on Planipennia, and published (over a period of some 40 years until 1938) descriptions of many hundreds of new taxa of various insect groups - 359 genera, 2082 species, 294 'varieties' of Planipennia (Monserrat 1986). Many of these were raised on small features and a very limited range of characters, so that careful reappraisal of his work is necessary to disclose the undoubted value of much of it. A number of his major syntheses remain useful starting points for later studies, as do those of Krüger. Handlirsch's (1906-1908) account of fossil insects remains indispensable, and contains some rearrangement of Planipennian families. The first major author on Planipennia based in North America, N. Banks, also produced many valuable papers from about 1890-late 1940s, and this period was marked also by substantial contributions from other workers, and constructive appraisal of the fauna of many parts of the world. P. Esben-Petersen (Denmark), F.M. Carpenter (Harvard), R.J. Tillyard (Australia) and D.E. Kimmins (London) are amongst those whose taxonomic work is still frequently cited. C.L. fVithycombe's (1925) synthesis of larval anatomy as a basis for phylogeny is still widely used, as is F. J. Killington's (1936, 1937) two-volume classic on British Neuroptera. Stitz' (1927) keys to Neuroptera of central Europe undoubtedly encouraged further interest in the order, and the extensive information on the European fauna has recently been synthesised by Aspöck, Aspöck and Holzel (1980), in a work which is an exemplary treatment of a regional fauna, and the envy of neuropterists working on lesser-known faunas elsewhere. Taxonomic knowledge of Planipennia in other parts of the world has been synthesised by a number of specialists: B. Tjeder's series of family revisions for southern Africa has been augmented by the work of M. W. Mansell on Nemopteridae and Myrmeleontidae; E.C. Zimmerman's (1957) synthesis of the tantalising Hawaiian fauna has brought at least partial order to a complex radiation of Chrysopidae; L.A. Stange's studies of (especially) American Myrmeleontidae are augmented for that region by P.A. Adams' studies on Chrysopidae and other families; H. Holzel has produced a number of synoptic papers on the middle eastern fauna, N. D. Penny on the Amazonian taxa, and T.R. New on Planipennia of the Australian region. Many of the classic taxonomic papers are noted by D. Hollis (1981), and ongoing publications are listed regularly in the specialist Journal 'Neuroptera International' (1980present). The 'Proceedings' of the first two International Symposia on Neuropterology (Gepp et al. 1984,1986) also reflect continuing progress. Foundations for sound biological understanding were also laid by early workers, such as Withycombe and R. C. Smith (summarised by Balduf 1939) and economic aspects, involving use of lacewings as biological control agents have received increasing attention. Many of the subtleties of using Chrysopidae, in particular, were pioneered in California (Hagen & Tassan 1972). This interest has acted as a considerable stimulus to understanding chrysopid biology, in particular, and the bulk of information summarised by Canard et al. (1984) is indicative of the complexity which is likely to occur in other families. As New (1986 a) noted,

2

Planipennia (Lacewings)

biological overgeneralisation is likely to have occurred in comments on most families, for which total published information is based o n fragmentary data, often from one or few species only.

Adults and larvae mostly predatory, more rarely feeding on plant exudates (larvae), or pollen or nectar (adults).

Despite the substantial amount of information now available, the Planipennia cannot be considered well-known. Virtually no biological information is available for most tropical taxa, and collections from many parts of the world continue to yield proportions of undescribed taxa. In general, the fauna of Europe and North America is now relatively well documented, and that of other parts of the Palaearctic, southern Africa and Australia moderately so. Planipennia of much of the Oriental region, of central and South America, and of northern and central parts of Africa, especially, need considerable further specialist collecting and appraisal.

The diverse families of Planipennia are united predominantly on larval synapomorphies - the form of the suctorial mouthparts, the discontinuity between mid-gut and hind-gut and the (often) cryptonephric Malpighian tubes, and this combination separates them from members of Megaloptera and Raphidioptera. Larvae of the latter groups have chewing mouthparts.

Diagnosis of order Minute to very large insects (fore wing length ca 2 - > 60 mm), most commonly medium-sized, comprising about 5500 recent species in 17 recent families. One of the most ancient groups of endopterygote insects, with an exarate decticous pupa formed within a (usually) silken cocoon which sometimes incorporates mineral or vegetable material. Oviparous, bisexual. Adults. Head moderate to large, orthognathous to hypognathous; chewing mouthparts, mandibles usually strong; antennae usually filiform or moniliform, sometimes clubbed, rarely pectinate; compound eyes large; ocelli frequently absent. Prothorax usually short: conspicously elongate in Mantispidae and some Berothidae; pterothorax sturdy; legs usually slender and cursorial, more rarely short and sturdy (Ascalaphidae) or fore legs strongly raptorial (Mantispidae, some Berothidae). Two pairs of subequal membranous wings; hind wing very rarely reduced or absent (some Hemerobiidae) or of markedly different form from fore wing (Nemopteridae); wings often patterned, rarely thickened or locally embossed; venation usually relatively complex (simplified in Coniopterygidae), major veins often with extensive 'end-twigging', trichosors often present around margin. Abdomen 10-segmented (apical fusion gives 9 apparent segments in Chrysopidae); female with exserted ovipositor only in Dilaridae and some Mantispidae; cerci absent, cercal callus usually present and bearing trichobothria, usually in a clearly defined field. Larvae. Usually active, campodeiform, occasionally scarabaeiform (Ithonidae) or vermiform (Mantispidae); prognathous, mouthparts strongly exserted, maxilla and mandible closely associated on each side to form 'sucking tube'; maxillary palpi absent; tarsi 1-segmented; midand hind-gut not connected; Malpighian tubes cryptonephric in terrestrial forms, more rarely so in aquatic taxa (Gaumont 1976). Mainly terrestrial and free living, rarely subterranean or parasitic; a few families with aquatic/semiaquatic larvae.

Adult unifying apomorphies for Planipennia are obscure. Adults are universally orthognathous, in contrast to prognathous Megaloptera and Raphidioptera, but this condition may be secondary (Henitig 1981), as larvae of all Planipennia are prognathous. Further adult synapomorphies include the 'ligula' of the labium, and the form of articulation between thorax and abdomen. According to Achtelig (1975), there is one joint between the laterotergite (which has the condyle) and epimeron, and another between epimeron (with condyle) and first sternite. In the wings, presence of trichosors - small thickenings on the wing margin between vein endings - is a feature shared between several early fossil forms and some modern families. Although the pronounced marginal 'twigging' of major wing veins separates many Planipennia (except Coniopterygidae) from Megaloptera, this feature is not strictly peculiar to Planipennia (Achtelig 1981). Because of the considerable diversity in form in Planipennia, with many of the families superficially seeming very different from each other and often having striking individual apomorphies, the family diagnoses given in the Systematic Account are relatively long. In particular, genitalic homologies between families are frequently not clear, and many groups have individual 'functional terminologies' which are not morphologically precise (Tjeder 1970, Acker 1960, Adams 1969, Aspock et al. 1980). These are related to morphological structure on p. 63. Yet, despite the lack of apparent synapomorphies, there is equally no reason to suggest that the Planipennia are other than monophyletic.

Palaeontology and Phylogeny Planipennia have a long evolutionary history and, although the precise affinity of some of the early 'neuropteroid' fossils remains enigmatic, they were clearly distinct by the Permian. The extinct order Glosselytrodea may be the sister group of the Planipennia (Sharov 1966, Rodendorf & Rasnitskyn 1980), although this order has alternatively been referred to the orthopteroid series. The Permian taxa, from Russia, Australia, United States and southern Africa, include a number of

Palaeontology and Phytogeny

species which are referred to wholly extinct families, but several recent families (including Nymphidae, Psychopsidae, Chrysopidae) were distinctive by the mid-Mesozoic. Many of the earliest fossils are known only from small fragments of wings, and their condition sometimes prevents confident appraisal of their relationships: some, indeed, have been subsequently transferred to orders other than Planipennia. As examples, the two taxa from the Lower Permian of Kansas described by Tillyard (1932, 1937) are now referred to Caloneurodea (Permobiella perspicua) (Martynov 1938, Carpenter 1943) and Glosselytrodea (Permoberotha villosa) (Martynova 1962) (Fig. 4). The latter has been claimed (Carpenter 1954) to be the oldest species of true Planipennia. Some other Permian taxa (including Palaemerobiidae, Permithonidae, Permopsychopsidae) are more distinctive. The Kansas Lower Permian deposits are considerably older than others which have so far yielded unambiguous Planipennia: one (undescribed) specimen from Kansas was regarded by MacLeod (1970) as a true Planipennian. The relationships of most Permian taxa to Recent Planipennia are completely unknown. Although the 'stem name' of some extinct families reflects some supposed resemblance of wing features to more modern forms, these are not confirmed. Martynova (1962) noted the following supposed affinities of fossil Planipennia families: Myrmeleontoidea: Solenoptilidae, Nymphitidae; Hemerobioidea: Kalligrammatidae, Brongniartiellidae, Palaemerobiidae, Sialidopsidae, Mesochrysopidae; Polystoechotidea ( = Osmyloidea of other authors): Permithonidae, Archeosmylidae, Osmylitidae, Mesopolystoechotidae, Osmylopsychopsidae. Schlüter (1986) recognised a total of 14 extinct families, many of which were grouped by Carpenter (1954) into the two 'families' Palaemerobiidae and Permithonidae, separated on the number of branches to vein Rs, and

3

corresponding to Martynova's 'Polystoechidea' and 'Hemerobiidea'. As Hennig (1981) noted, Martynova's division character, of vein Sc ending in R (Polystoechidea) or on C (Hemerobiidea) does not invariably hold. Several early fossil forms show specialised wing features which relate them to living taxa. The Jurassic nymphitid Chrysoleonites ocellatus, for example, has a moderately developed anterior Banksian line in the fore wing (Martynova 1962). Of Recent families, the earliest to appear in the fossil record are Psychopsidae, Chrysopidae (or Mesochrysopidae, = Chrysopidae: Mesochrysinae) and Osmylidae and related taxa. Some Nymphitidae are perhaps only doubtfully distinct from Recent Nymphidae. All occur in Triassic strata, Psychopsidae from Australia (Ipswich) {Tillyard 1922, Riek 1956) and Nymphitidae from Russia (Martynova 1949). Psychopsid-like broadwinged Planipennia appear to have radiated extensively during the early Mesozoic, and have been placed in several families, such as Prohemerobiidae, Osmylopsychopsidae and Kalligrammatidae. Kalligramma haeckeli (Figsl, 2), from the Upper Jurassic of Solnhofen (Bavaria) is one of the most spectacular lacewing fossils, being brightly coloured and with conspicuous 'eyespots' on all wings. Kalligrammatidae are very broad winged, with the hind wing broader than the fore wing. Triassopsychops superba (Fig. 3), from the Upper Triassic of Queensland, was regarded by Tillyard as a probable direct ancestor of the largest Recent psychopsid, Megapsychops illidgei (Figs 44, 45). Mesopsychops hospes (U. Jurassic, Bavaria, Fig. 5) has been referred to Prohemerobiidae, and seems allied to Psychopsidae in wing shape and complexity of venation. The Bavarian Jurassic Mesonymphes hageni (Nymphitidae) may be a true nymphid (Adams 1958). Palaemerobiidae are perhaps close to Berothidae. Some putative genera of fossils are rather diverse in wing structure (Fig. 8).

Fig. 1. Kalligramma haeckeli (Kalligrammatidae), one of the largest-known Planipennia (wing span ca 24 cm), from the Jurassic of Bavaria. This reconstruction from Handlirsch (1908) has appeared in several texts, but more recent appraisal suggests that the fore wings and hind wings have been transposed. Note conspicuous 'eyespots', and abundant crossveins.

4

Planipennia (Lacewings) Sc

Fig. 2. Kalligramma 1962).

haeckeli: wing venation

(Martynova

Upper Triassic of Queensland, Australia ( Tillyard 1922 b), fore wing.

An array of osmylid-like forms is known from the Triassic of Queensland (Riek 1956) and were originally placed in several families. As Riek commented this was 'not because they are so very different, but because they show marked tendencies towards Recent families. However, they are not specialised enough in most cases to be considered in Recent families'. Thus Archaeosmylidae were considered to resemble Recent Osmylidae: Protosmylinae, and Osmylopsychops and Archepsychops were referred to Osmylopsychopsidae. Lithosmylidea was referred to Kempyninae. The wide spectrum of Mesozoic 'Osmylid-like Planipennia' has been critically reappraised by

Fig. 4. Two Permian fossils from Kansas: A) Permoberotha villosa (sometimes allocated to Glosselytrodea) and B) Permobiella perspicua (allocated by Tillyard to Permoberothidae (Tillyard 1932,1937; A from Carpenter 1943a).

Fig. 5. Mesopsychops hospes (Prohemerobiidae) from the upper Jurassic of Bavaria. (Reconstruction by Handlirsch 1908).

Lambkin (1988). Grammosmylus acuminatus (Jurassic, USSR) was retained in Grammosmylidae, with unknown affinities. Kasachstania and Lithosmylidea are similar to Osmylidae or Polystoechotidae, but apparently distinct from either, and several others seem referable to one or other of these families. The Cretaceous Palaeoleon ferrogenetus from Canada may be a myrmeleontid. Coniopterygidae have also been long distinct. Although their fossil record is poor, one clearly recognisable species is known from the Upper Jurassic of Kazakstan. Juraconiopteryx zherichitii is the earliest well-defined coniopterygid, and is

Palaeontology and Phylogeny

Fig. 6. Glaesoconis cretica (Coniopterygidae). Two specimens from Cretaceous amber, Siberia (Meinander 1975).

Fig. 7. Two specimens referred by Panfilov (1980) to Mesithone: differences in details of crossvein pattern.

maculata (above), magna (below). Note substantial

Fig. 8. Mesozoic Chrysopidae: a) Mesochrysopa zitteli, Upper Jurassic, Bavaria (Reconstruction by Handlirsch 1908); b) Mesypochrysa reducta, Siberia (from Panfilov 1980). Note relatively narrow elongate wings, with few defined gradate series.

6

referable to Aleuropteryginae (Meinander 1975). A further record of a Jurassic species is controversial - although known as Archiconiopteryx, it has also been considered to be an homopteran. Glaesoconis (Fig. 6) is known from cretaceous amber from Siberia (Meinander 1975) and Lebanon ( Whalley 1980), and several taxa are known from more recent european amber and african copal: one Baltic amber (?middle Eocene) form is referred to the extant genus Hemisemidalis {Meinander 1975). Two Chrysopidae, Mesochrysopa zitteli (Fig. 8) and Mesypochrysa latipennis occur in the Upper Jurassic, the former from both the USSR and Germany, and are apparently referable to the stem-group of Recent Chrysopidae. Mesochrysopa has been claimed to have a myrmeleontid appearance because of the long slender wings. Both genera are now usually referred to the extinct subfamily Mesochrysinae, rather than to a distinct family (Adams 1967). Cretaceous amber from several widely separated localities has yielded Planipennia. The only record from North America is the Canadian Plesiorobius canadensis (Fig. 13) which was referred to Berothidae (Klimaszewski & Kevan 1986), though with some slight doubt as characteristic hind wing features are not adequately visible. It is clearly only remotely related to two Berothidae found in Lower Cretaceous amber from Lebanon ( Whalley 1980). Banoberotha (Fig. 12) shows features of both Berothidae and Sisyridae, but Paraberotha has raptorial forelegs and was thus referred to Rhachiberothinae, as is a specimen from cenomanian amber of N.W. France (Retinoberotha stuermeri) (Schlüter & Stuemer 1984, Fig. 13). A mantispid, Fera venatrix, from amber (probably Baltic) washed up on the east coast of Britain also resembles Rhachiberothinae in some features (Whalley 1983) and a more typical mantispid occurs in the Bembridge Marls of the Isle of Wight (late Eocene/early Oligocene) (Jarzembowski 1980), together with Sisyridae, Hemerobiidae and Chrysopidae. Lebanese amber also yielded an antlion. Tertiary fossils are much more numerous than older forms, both in shales and Baltic amber, and more closely approach modern taxa. Two Miocene Osmylidae from the Florissant Shales (Colorado) (Fig. 10) have been referred to Recent subfamilies (Carpenter 1943 b), and are of considerable zoogeographical interest, as Osmylidae do not now occur in North America. Likewise, the Miocene Halter americana (Fig. 11) is undoubtedly an American nemopterid. Baltic amber is a particularly rich source of Planipennia (MacLeod 1970). Hageris (1856) account of this fauna enumerated Coniopterygidae, Hemerobiidae, Nymphidae, Osmylidae and Neurorthidae, to which MacLeod added Berothidae, Psychopsidae and Sisyridae, as well as larvae of Psychopsidae,

Planipennia (Lacewings)

Ascalaphidae and Nymphidae. As MacLeod noted, the putative absence of Chrysopidae from Baltic amber is anomalous, as is the high relative abundance of Neurorthidae. This lower Oligocene material includes some spectacularly preserved specimens, such as the larvae of Neadelphus protae (Ascalaphidae) (Fig. 15) and IPronymphes mengeanus (Nymphidae). The psychopsid Propsychopsis (two or three species, Fig. 14) confirms that this now geographically restricted family had a much broader distribution until relatively recently. The Oligocene (Florissant, Colorado) 'Polystoechotes' piperatus also seems to be a psychopsid (MacLeod 1970), and this family is also commonly represented in early Eocene Danish 'Mo-Clay' (Larsson 1978), together with Hemerobiidae and Chrysopidae. Early Miocene shales from North America and Germany have also yielded Chrysopidae: Nothochrysinae (Adams 1967, Schlüter 1984) and the north German Pliocene has produced a species attributed to the Recent genus Hypochrysodes by Schlüter (1982) (Fig. 9). With the exception of an unnamed Eocene/Oligocene chrysopid from the Isle of Wight (Jarzembowski 1980) all known Tertiary fossil Chrysopidae are Nothochrysinae rather than the predominant Recent subfamily, Chrysopinae.

Fig. 9. A more modern form of fossil chrysopid: Hypochrysodes hercyniensis, Pliocene, North Germany (Schlüter 1982).

The fragmentary fossil record is therefore sufficient to show that several Recent families of Planipennia have been distinct for a considerable period, and that some have apparently been much more widely distributed in the past than they are at present. Some groups, such as Coniopterygidae and Psychopsidae, seem to have changed little since at least the Lower Jurassic, but a number of other forms have become extinct during evolution of the Planipennia. The wide array of Baltic amber forms are all clearly referable to Recent families. Detailed phylogenetic relationships between families are difficult to appraise, and various authors have suggested very different affinities for some of the families, depending on whether adult or larval features, or a combination of characters are assessed. Larval features, which are seemingly more conservative (and, therefore, more reliably assessable) than adult features, suggest that Plani-

Palaeontology and Phylogeny

7

pennia predominantly comprise two major evolutionary lines. 'Hemerobiiformia' includes the presumed more primitive and more generalised feeders with a relatively conventional head and jaw morphology (maxilla at least as robust as mandible; mandible straight or slightly curved, without teeth, base dilated; medial ventral surface of head entirely composed of maxillae [cardo, stipes] and by labium; tentorium relatively unspecialised; long antennae with few segments; 2 - 8 subequal labial palp segments from undivided prelabium). The 'Myrmeleontiformia' have larvae which are more commonly 'ambushers' rather than 'chasers' of prey. Their features include: maxilla never as broad as mandible; mandible robust, curved, often with teeth along inner side, basally constricted; ventral surface of head heavily sclerotised, sclerites of maxilla and labium restricted to medial region; tentorium specialised; short antenna with 10-12 segments; 2 - 4 segmented labial palp from divided prelabium. These major divisions are sometimes considered as infraorders (Henry 1982 b) but, within each, relationships are by no means clear and several families have been allocated (on adult features) to both divisions at various times.

Fig. 10. Two Miocene Osmylidae from Florissant, Colorado. a) Lithosmylus columbianus, b) Osmylidea requieta. From Carpenter (1943 b).

Fig. 11. A Miocene nemopterid, Halter americana, from Colorado (Handlirsch 1908).

^^IlMlQim:

Fig. 12. A presumed berothid, Banoberotha enigmatica, from Lower Cretaceous amber, Lebanon, differs from Recent Berothidae in having all costal crossveins simple, rather than branched (Whalley 1980).

A phylogenetic scheme proposed by Withycombe (1925) (Fig. 16) has formed the basis for much recent discussion. It is now generally accepted that Coniopterygidae is very distinct from all other Planipennia, and seems to have no close relatives: it thus constitutes a distinct superfamily, Coniopterygoidea. Ithonidae is also archaic (Ithonoidea), and Rapismatidae and Polystoechotidae have at times been placed with this family. Both Coniopterygidae and Ithonidae share primitive features with the Megaloptera, and are possibly sister groups to all other Planipennia (Meinander 1972). Mantispidae and Berothidae are closely related and the Rhachiberothinae are perhaps transitional between these families. Dilaridae have been variously allied with this group, or with Osmyloidea, or with Hemerobioidea. 'Osmyloidea' is widely regarded as a grouping of convenience, and some families placed there are likely to be convergent (for example, by having adopted an aquatic/semiaquatic larval existence) rather than being closely related. Dilaridae and Osmylidae, for example, have been allied because of the presence of ocelli, which have been lost in all other groups. Neurorthidae appear to be particularly archaic in this series. Hemerobiidae and Chrysopidae are undoubtedly closely related, and larvae have most features in common. Larvae of Psychopsidae in some ways indicate a closer relationship of this family to Myrmeleontoidea, though Psychopsidae are allied with Hemerobioidea in some accounts: this affinity is more closely suggested by some venational features. The long fossil history of psychopsid-like forms suggests that these may

8

Planipennia (Lacewings)

Fig. 13. A) A probable berothid, Plesiorobius canadensis, from Canadian Cretaceous amber (Klimaszewskt & Kevan 1986); B) Retinoberotha stuermeri from Cenomanian amber in France (Schlüter & Sturmer 1984).

Fig. 14. Propsychopsis lapicidae: a psychopsid from Baltic amber (MacLeod 1970). (n = nygma; b = basal free part of MA).

have been present before the major larval division of Planipennia into 'infraorders'. Rapismatidae are a very isolated archaic family. The 'Hemerobiiformia' could, therefore, comprise up to five superfamilies, together incorporating about 70 per cent of extant Planipennia and including a maximum of 13 families. The 'Myrmeleontiformia' ( = Myrmelontoidea) are not as diverse and four families, at least, appear to be closely related. Nymphidae are widely thought to be the most primitive family of this series, and probably constitute a stem group leading, on the

one hand, to Nemopteridae and on the other to Myrmeleontidae and Ascalaphidae. Stilbopterygidae, formerly regarded as a further family of Myrmeleontoidea, was based on an artificial assemblage of taxa, and its members are now allocated variously to Myrmeleontidae or Ascalaphidae. Nymphidae are themselves 'diverse, and this group historically comprises members of two families (Myiodactylidae, Nymphidae) which differ considerably in larval form but are clearly closely related (one family) on venation and genitalia. Some broadwinged species of Nymphidae (the genera formerly placed in Myiodacty-

Palaeontology and Phylogeny

Fig. 15. Larva of an ascalaphid, Neadelphus protae, from Oligocene Baltic amber (described by MacLeod 1970, illustration from Henry 1976). Nemopteridae ,— 4I /

Psychopsidae j

\

/ \

\ \

L

Chrysopidae

\

:

Hemerobiidae Polystoechotidae

\

\

/

\ \

Apochrysidae

j

\

\

Myrmeleontidae Nymphidae

I—( /

Ascalaphidae

—r \

\

tr \

\ \

\ \

r

Berothidae Osmylidae

' \

*

Dilaridae ^

^

Mantispidae

Sisyridae Coniopterygidae Ithonidae

Fig. 16. Withycombe's (1925) phylogeny of the Planipennia. Note differences from Fig. 17: Psychopsidae are more closely allied with myrmeleontoid families, Apochrysidae and Chrysopidae are (following Handlirsch) maintained as distinct. See also scheme proposed by Tillyard (1919).

10

Planipennia (Lacewings)

Fig. 17. Schliiter's (1986) summary of suggested phylogeny and stratigraphie history of families of Planipennia. See text for details of relationships between families and possible other relationships. Compare also with Fig. 16. Numbers at top of figure are approximate numbers of described species.

lidae) are superficially rather similar to some Osmylidae, and the points of division between many of the presumed superfamilies are not clear. There is need for a full reassessment of interfamily relationships in the Planipennia, and for critical reexamination of many of the described fossil species. A recent scheme by Schliiter (1986) is shown in Fig. 17. Indications of diversity and relationships within each Recent family are given in the Systematic Account. Although assessment of relationships within each family is based almost entirely on structural features - predominantly of adults, though larval features are often also useful recent work using electrophoretic data for European Chrysopidae (e.g. Bullini et al. 1983) demonstrates the potential utility of such additional approaches.

Systematic account Key to families This key does not include superfamily groupings. It is designed for simple practical use, and should not be used for implications on phylogeny. Any doubtful diagnoses should be checked against the details given for each family following the key. The taxonomic references provided for each family are not comprehensive, but are some of the more important key references for each. See also Hollis (1981). 1 Very small insects: fore wing length to about 5 mm, usually smaller; wings and much of body covered with waxy or mealy secretion, usually white or grey; costal area with, at most, 1 or 2 (basal) crossveins; rarely non-

11

Systematic account

waxy and with venation reticulate (Figs 18, 19) Coniopterygidae - N o t as above: larger, not waxy, costal area with more numerous crossveins 2 2 Fore wing and hind wing of markedly different shape: hind wing greatly elongated, threadlike or expanded near apex (Fig. 5 7 ) . . Nemopteridae Fore wing and hind wing of generally similar shape, though hind wing often shorter than fore wing, more rarely longer 3 3 Fore legs raptorial (Fig. 75), femur strongly thickened; prothorax elongated 4 Fore legs not raptorial; prothorax not markedly elongated 5 4 Fore wing costal crossveins often forked; trichosors present Berothidae (Rhachiberothinae) Fore wing costal crossveins simple; trichosors absent Mantispidae 5 Antennae filiform or moniliform, occasionally pectinate (male Dilaridae), never clubbed or with apex markedly broadened 6 Antennae with distinct apical club, or apex broadened 17 6 Stout-bodied, with hind wing very broad near base (usually hairy, head often partially retracted under pronotum) 7 - N o t as above: if, rarely, body stout, hind wing no broader than fore wing near base 8 7 Tibial spurs present; claws elongate; trichosors well developed (Australia, N. America) Ithonidae Tibial spurs absent; claws broad, with small subapical projection; trichosors weakly defined (Oriental) Rapismatidae 8 True ocelli present, at least represented by raised tubercles on vertex Osmylidae True ocelli absent (tubercles present in some Dilaridae and Psychopsidae, q.v.) 9 9 Fore wing vein Sc parallel with and fused distally with R t and Rs to form 'vena triplica' (Fig. 44) (Wings very broad, Rs with many branches, crossveins in defined gradate series, head often retracted under prothorax) Psychopsidae - N o t as above: no vena triplica and without above combination of subsidiary features . . . 10 10 Veins Sc and R , fused near apex of wing . . . 11 Veins Sc and R ! not fused near apex of wing 12 11 Both wings with numerous irregular crossveins, including many from R , to Rs; no recurrent humeral vein Nymphidae Both wings with 2 defined gradate series of crossveins, few R , - R s crossveins; recurrent humeral vein present Polystoechotidae 12 Veins Sc and R ^ separate apically, not connected by crossvein (male: antennae pectinate; female: ovipositor exserted; wings usually

-

13 14

-

15 16

-

17

-

densely hairy) ( F i g s 3 0 - 3 2 ) Dilaridae Veins Sc and R , connected by crossveins near apex (male: antennae simple; female: ovipositor not exserted) 13 Fore wing with at least 2 apparent Rs veins arising from R i (Fig. 40) . . . . Hemerobiidae Fore wing with only single Rs, arising f r o m R , near base of wing 14 Hind wing vein CuA not conspicuously close to hind margin (medium to large, often green; trichosors absent) Chrysopidae Hind wing vein CuA close to hind margin for some distance (rarely green, often small; trichosors sometimes present) 15 Fore wing costal crossveins usually all simple; wings not hairy (Fig. 28) Sisyridae Fore wing with at least some costal crossveins forked 16 Fore wing with several Sc-R, crossveins; wings not hairy (occasional Sisyridae may key here - see genitalic features in family diagnoses for separation) Neurorthidae Fore wing usually with only basal Sc-R! crossvein, very rarely a second crossvein at or beyond half wing length; wings often densely hairy of with flattened scales on veins Berothidae Antennae longer than half length of fore wing, strongly clubbed (Fig. 54) (very rarely (Albardia) antennae very short and body stout and strongly hairy) Ascalaphidae Antennae usually much shorter than half fore wing length, more or less gradually clubbed or expanded at apex Myrmeleontidae

Family Coniopterygidae Small lacewings with reduced venation; fore wing length c 2 - 5 m m . Body, wings, legs often coated with white/grey wax or 'meal' secreted by hypodermal glands. Head with temporal suture welldefined, other dorsal sutures indistinct; clypeus and labrum short; genae small (Coniopteryginae) or larger (Aleuropteryginae); antennal sockets often linked by unsclerotised central frontal area; antennal segments c l 6 - 6 0 , number relatively constant in some taxa; scape and pedicel sometimes ornamented (males), flagellar segments moniliform, rarely expanded to discoidal, sometimes with scale-like hairs in distinct whorls; ocelli absent. Mandibles small; maxillae welldeveloped, lacinia with comb of strong hairs on inner edge, galea 1-segmented (Coniopteryginae) or 3-segmented (Aleuropteryginae), palpi 5-segmented with distal segment relatively long, segments 3 - 5 sometimes modified in male; labium well-developed, palpi 3-segmented, distal segment often with large area of short sensory hairs, paraglossa absent. Prothorax short, usually very lightly sclerotised; meso- and meta-thorax more heavily sclerotised. Legs slender, cursorial. Most

12

taxa with 2 pairs of broad subequal wings (hind wings sometimes reduced; rarely apterous or both wings slender) held roof-like over dorsum; trichosors absent; membrane unicolorous or variously spotted or mottled, usually with brown or black; marginal setae present; macrotrichia on most longitudinal veins. Venation: never more than 2 (basal) costal crossveins; fore wing Sc distally forked, posterior branch resembling distal part o f R i ; R and M fused basally; Rs separating from R[ near middle of wing, usually forked, posterior branch sometimes resembling distal part of M; M usually forked, 1 or 2 R-M crossveins, sometimes 2 long setae on M near middle of wing (Aleuropteryginae); Cu usually forking near base but sometimes more distally, one M-Cu crossvein; 2 anal veins; whole venation rarely (Brucheiser) reticulate and more obscure. Hind wing vein Sc and fore wing vein Rs separate from R, near wing base (Aleuropteryginae) or more distally (Coniopteryginae); hind wing with crossvein from Ri-Rs; M usually forked (not in Coniopteryx, most Coniocompsini); R-M crossvein present; Cu forked near base; 2 anal veins. Abdomen (Fig. 20) well sclerotised, except genitalia: Aleuropteryginae with spiracles on segments I - V I I , Coniopteryginae apparently lacking spiracles on segment VIII; wax glands on tergites and sternites, usually in characteristic pattern of lines or bands; Aleuropteryginae with plicaturae. Female: sternite IX only rarely distinct; lateral gonapophyses short, sometimes fused, without styli; subanale (sternite X) often present. Male: tergite IX and sternite IX fused into well-sclerotised ring, hypandrium usually incorporated (fused coxopodites IX), styli almost always present; gonarcus usually not distinct; sternite X usually present - in Coniopteryginae as a small plate, in Aleuroptery-

Planipennia (Lacewings)

ginae often more complex; parameres elongate; true penis present, formed of mesomeres and (Aleuropteryginae) parameres; segment XI weakly evident, no trichobothria or cercal callus. Common names: Dusty wings, mealy wings. About 300 recent species. Monographed by Meinander (1972), Coniopterygidae are the smallest Planipennia and superficially resemble Aleyrodidae (Homoptera) in general appearance. Three subfamilies are recognised, one of which is anomalous. Key to subfamilies 1 2

-

Wing venation reticulate (Fig. 19) Brucheiserinae Wing venation predominantly longitudinal.. 2 Fore wing with 1 R-M crossvein; hind wing with Rs not branching from R , very near wing base (Fig. 18 B) Coniopteryginae Fore wing with 2 R-M crossveins near middle of wing; hind wing with Rs branching from R, very near wing base (Fig. 18 A) Aleuropteryginae

Brucheiserinae. Contains only Brucheiser (2 spp.), highly unusual neotropical forms treated by Riek (1975) as a distinct family, Brucheiseridae, a separation which seems not to be justified. Wing venation highly characteristic. Coniopteryginae. A large group, with the 2 tribes (Coniopterygini, Conwentziini) separable only on male genitalia but most genera separable on venational features.

Fig. 18. Wings of A) Heteroconis ornata and B) Neosemidalis nervalis, as examples of Aleuropteryginae and Coniopteryginae, respectively (see text) (from Meinander 1972).

Systematic account

Fig. 19. Coniopterygidae: Brucheiserinae. Brucheiser argentinus. (A) Lateral aspect of whole insect, and B) wing venation (from Riek 1975).

Representative genera: Neosemidalis (Australia), Coniopteryx (cosmopolitan), Conwentzia (holarctic, India, S. Africa), Semidalis (cosmopolitan except Australia). Aleuropteryginae. Divisible into 3 tribes, as follows 1 Hind wing R r R s crossvein reaching Rs on R2 + 3 Fontenelleini - Hind wing R r R s crossvein reaching Rs on stem or fork 2 2 M forked in both wings, anterior branch in fore wing coalescing or connected with R 4 + 5 Aleuropterygini - M simple in both wings or forked but anterior branch in fore wing not connected with R 4 + 5 Coniocompsini Representative genera: Aleuropteryx (holarctic), Heteroconis (Asia, Australia), Coniocompsa (Old World tropics), Cryptoscenea (Australian region), Helicoconis (holarctic, Africa), Spiloconis (southeast Asia, Australia). Family Rapismatidae Large sturdy lacewings with complex venation, fore wing length 19-35 mm. Head partially retracted under prothorax; eyes large; ocelli absent;

antennae short ( 4 - 1 1 mm), moniliform or slightly serrate, scape and pedicel simple, flagellar segments with whorls of short to moderately long setae; mandibles short and broad, palpi short. Thorax broad, pronotum shield-like; legs short, hairy, without spines or spurs, tarsal claws basally broad, with incipient subapical tooth. Wings (Fig. 21) long and broad, subequal; small trichosors present; usually pale yellowish or green, membrane sometimes maculated. Fore wing: costal area basally broad, recurrent humeral vein present; numerous subcostal crossveins usually forked, often interlinked, especially in basal half; Sc and R t parallel, linked by many crossveins, running free to wing margin; Rs + MA separates from R j close to wing base; Rs pectinate; MA separating near base of Rs, multiply forked; M P forked near base, M P 2 usually multiply forked; CuA and CuP forked; 3 anal veins and simple jugal vein; whole wing with numerous crossveins. Hind wing overall similar to fore wing, except costal crossveins usually less forked and less extensively linked, costal area relatively narrower. Both wings with single nygma between bases of Rs + MA and MP. Abdomen well sclerotised, broad. Female (Fig. 22A, B): broad sugenital plate with median notch; spermatheca simple, lateral gonapophyses rounded. Male (Fig. 22 C): gonarcus well developed; gonocoxites attached at

14

Planipennia (Lacewings)

Fig. 20. Terminalia of Coniopterygidae: A, abdomen of female Helicoconis capenis (Tjeder 1957); B, abdomen of male Aleuropteryx juniperi; C - F , male genitalia of A.junipert lateral; caudal; penis in dorsal aspect; ventral aspect, except penis {Meinander 1972) (epr, ectoproct; gl, lateral gonapophysis; pi, plicatura; app IX, appendage of sternite IX; apo IX, apophysis of sternite IX; p, penis; pro IX, process of sternite IX; tp, transverse plate).

Fig. 21. Rapismatidae: Rapisma viridipenne, wing venation (from Barnard 1981).

sides of gonarcus, sometimes bilobed and lobes sometimes spined or rugose; mediuncus lobes prominent, fused; hypandrium internum small. Slight sexual dimorphism in wing shape and head size. One genus, Rapisma, with 16 species. Limited to Oriental Region (Nepal, Burma, Malaysia, Indonesia) and predominantly montane (Barnard 1981, Barnard and New 1985).

Family Ithonidae Large sturdy lacewings with complex venation, fore wing length 1 5 - 3 0 m m (Fig.23). Head broad, short; genae short; labrum slightly excavated medially; ocelli absent; antennae filiform or flagellar segments slightly broadened (especially near base of antenna), moderately long (c. 0 . 4 - 0 . 6 fore wing length), 4 0 - 5 0 segmented. Mandibles short to elongate (especially males), without inner teeth; maxillary palpi 5-segmented,

15

Systematic account

, 2mm Fig. 22. Terminalia of Rapismatidae. A, B, Rapisma viridipenne, female, lateral and ventral; C, genitalia of male R. tamilanum, ventral (gcx, gonocoxite; gl, lateral gonapophysis; gs, gonarcus; hi, hypandrium internum; sgp, subgenital plate; sp, spermatheca; uml, mediuncus lobes) (Barnard 1981).

Fig. 23. Ithonidae: A) Oliarces clara, male (USA) and B) Ithonefusca, wing base and very stout body.

galea with small apical process, basigalea with inner fringe of long hairs, stipes long, cardo short; labial palpi 3-segmented, rest of labium considerably reduced. Head partially retracted under broad prothorax; pterothorax broad; legs mode-

female (Australia): note dense venation, broad hind

rately long; tarsi 5-segmented, claws simple; tibiae with pair of strong apical spurs. Fore wing somewhat thickened (Australian taxa); both wings elongate, held roof-like over dorsum at rest; trichosors present; hind wing with broad basal

16

Planipennia (Lacewings)

attachment and anal fan; 2 nygmata on fore wing, 1 on hind wing; pterostigma weakly defined; fore wing costal space slightly broadened, recurrent humeral vein present; costal crossveins sometimes branched or interconnected; Sc and R connected by single basal crossvein and 1 or more crossveins near apex; Rs + MA separating from R, near base, Rs then pectinate; MA usually forked, MP forked and branches pectinate; CuA and CuP branched; 3 anal veins present; crossveins moderately numerous. Abdomen stout, cylindrical, shorter than wings. Female (Fig. 24 B) with unusual apical process beyond ectoproct and tergite VIII, comprising dorsal 'keel' ('psammorotrum' or 'sand plough') and ventral digitate gonopod. Male (Fig. 24A): ectoprocts elongated to form 'claspers'; sternite IX forming distinct hypandrium; gonarcus incomplete, paired or triangular plates present. A small family containing 4 genera and about 15 species. Oliarces (1 sp., Fig. 23 A) is from North America and all others (Ithone (Fig. 23 B), Megalithone, Varnia) are limited to Australia, predominantly occurring in sandy or drier regions (Riek 1974 a).

B Fig. 24. Tcrminalia of Ithonidae: apex of abdomen of (A) male and (B) female Ithone fusca, lateral (Riek 1974a).

Family Osmylidae Slender, moderate-sized lacewings, fore wing length 15-30 mm. Head short and rounded; 3 ocelli present, often rather indistinct (Spilosmylinae), absent only in Gumilla (S. America); eyes moderately large; antennae filiform, usually about 1/3-1/2 fore wing length (longer in Gumilla). Mandibles pointed, usually asymmetrical; maxillary palpi long, 5-segmented; labial palpi 3segmented, apical segment with outer sensory area. Pronotum usually narrower than pterothorax, well sclerotised and usually longer than wide. Legs slender, relatively short to rather long; coxae long - in females of some taxa, fore coxa has basal lobe/process or row/group of pedicellate setae; small tibial spurs sometimes present; claws simple. Wings subequal, elongate, broadly oval or falcate at apex; trichosors present except near

base; nygmata present; fore wing, particularly, may be variously marked with brown, grey or (occasionally) steel-blue, black, and/or yellow/cream, sometimes with embossed spot(s) on posterior margins (many Spilosmylinae). Costal space relatively broad; numerous crossveins (simple or branched), sometimes interconnected; humeral vein simple; pterostigma distinct; Sc and R ! closely parallel, coalesce below pterostigma, usually with only single (basal) Sc-R crossvein, occasionally more numerous crossveins (Figs 25 A, 27 A); Rs and MA with common stem, Rs pectinate; M P forked, position of fork variable; Cu forked near base of wing; 3 anal veins present, 1A and 2 A usually with several branches; crossveins numerous, predominantly in discal areas of wings; usually 2 nygmata on each wing, these often weakly defined. Abdomen with welldefined tergites and sternites and large pleural regions, 8 pairs of spiracles. Ectoproct and cercal callus (with numerous small trichobothria) clearly defined; tergites V I I - I X or VIII and IX may be closely associated or variously fused (some Stenosmylinae). Female (Fig. 86): tergite IX prolonged ventrally; gonapophyses laterales long, usually slender, with small apical style; subgenitale below tergite VIII, often postgenitale below tergite IX; 2 spermathecae present, sometimes with accessory glands. Male: ectoprocts usually fused dorsally; tergite IX often ventrally extended, occasionally with dorsal prominences; gonarcus complete, usually with entoprocessus; sometimes a lateral rod ('baculum') connected to end of gonarcus arch; parameres free or fused; sometimes a transverse arched sclerite ('subarcus') above parameres; small hypandrium internum present. Osmylidae are widespread but are apparently absent from North America - with the possible exception of an anomalous species from Mexico, Naradona mexicana, which has not been appraised critically. About 160 species have been described, and these are divided (mainly on rather simplistic venational features) amongst up to 8 subfamilies (Krüger 1912-1915). Key to subfamilies 1 2 3 -

Antennae as long, or longer than, fore wing; ocelli absent Gumillinae Antennae relatively shorter; at least traces of ocelli present 2 Fore wing costal crossveins predominantly forked 3 Fore wing costal crossveins simple, occasionally with few forked 4 Hind wing vein M P 2 simple (Fig. 26) (Palaearctic) Osmylinae Hind wing vein M P 2 forked in distal half of wing (Fig. 27 B) (S. America, New Zealand, Australia) Kempyninae

17

Systematic account

4 5 6

-

7 -

Fore wing with numerous subcostal crossveins (Fig. 25 A) Porisminae Fore wing with single, basal, subcostal crossvein (rarely traces of few more) 5 Fore wing vein M P forking near base of wing 6 Fore wing vein MP forking at or beyond half length of wing 7 Relatively few crossveins: usually only small number basal to two main gradate series . . . Protosmylinae Crossveins more numerous: usually at least six series basal to two outer gradate series (fore wing often with embossed spot(s) on posterior margin) Spilosmylinae Fore wing veins M A and Rs separate near base of wing Stenosmylinae Fore wing veins M A and Rs separate at about one third length of wing (Fig. 25 B) Eidoporisminae

The following four subfamilies are southern elements. Porisminae. A single very distinctive brightly coloured species from mainland south eastern Australia, Porismus strigatus (Fig. 27 A) (New 1983 a), Eidoporisminae. Contains only Eidoporismus pulchellus, from eastern Australia (New 1983 a). Kempyninae. Contains some of the largest and most spectacular Osmylidae, and found in temperate South America, New Zealand and Australia: apparently most diverse in Australia. Included

Osmylinae. Predominantly eastern Palaearctic, with one species (Osmylus fulvicephalus) widespread in western Europe. About 20 species, with the major genus Osmylus (Makarkin 1985). In many features, Osmylinae and Kempyninae appear to intergrade, and are best separated by discrete geographical ranges. Protosmylinae. About 6 species, predominantly from Japan and the Oriental region (Gryposmylus, Heter osmylus). Spilosmylinae. The most diverse group of Osmylidae, widely distributed in Africa, eastern Palaearctic, Oriental region to northern Australia. Many species have embossed fore wing spot(s) on the posterior margin. The predominant genus (possibly a complex) is Spilosmylus, with about 90 described species, 35 of them from New Guinea. Others include Lysmus, Thyridosmylus. Gumillinae. Contains 2 anomalous american species with very long antennae. They have historically been referred to Chrysopidae (Adams 1977).

Fig. 26. Osmylidae: Osmylus fulvicephalus (Osmylinae) ( Ward 1965).

MA Fig. 25. Wings of Osmylidae: A, Porismus strigatus (Porisminae); B, Eidoporismus pulchellus (Eidoporisminae) (New 1983a).

18

Planipennia (Lacewings)

Fig. 27. Osmylidae: A) Porismus strigatus

(Porisminae); B) Australysmus

lacustris

(Kempyninae).

genera Kempynus, Australysmus (Fig. 27 B), Clydosmylus (Kimmins 1940 - as Kalosmylinae, Adams 1971, New 1983 b), totalling about 20 species. See comments under Osmylinae. Stenosmylinae. Found in temperate South America and Australia, most diverse in the latter, especially in the south east. Representative genera: Stenosmylus, Stenolysmus, Oedosmylus, Carinosmylus, totalling about 20 species (Kimmins 1940, Adams 1971, New 1986b).

3A

2A

M

Cu2

Cui •

Family Sisyridae Small delicate lacewings, fore wing length 4 - 1 0 mm. Head short and rounded; ocelli absent; antennae moniliform to filiform, about half fore wing length; mandibles acutely pointed, usually slightly asymmetrical; maxillary palpi long, 5segmented; labial palpi shorter, 3-segmented.

Fig. 28. Sisyridae: Wing venation

(Tjeder 1961).

of Sisyra

producta

Systematic account

/ ePr

Fig. 29. Terminalia of Sisyridae: A, apex of female abdomen of Sisyra producta, lateral; B, C, apex of male abdomen of S. fuscata, lateral and caudal (a, anus; ent, entoprocessus; epr, ectoproct; gl, lateral gonapophysis; gs, gonarcus; hyi, hypandrium internum; pa, parameres; tr, trichobothria). Note strongly reduced abdominal sclerites (.Tjeder 1957).

Pronotum short, broad. Pterothorax large. Legs long, slender; fore coxae very long; claws simple. Wings subequal, oval (Fig. 28); trichosors present around outer half, sometimes weakly defined on hind wing; nygmata absent; wings usually pale grey or brown, occasionally slightly mottled. Costal space narrow, with few simple crossveins predominantly in basal half; pterostigmal veins indistinct; Sc and R x indistinctly fused apically; no basal crossveins between Sc and R); Rs and R j separate near base of wing, apparent Rs with several branches and linked to R ! by 2 (fore wing) or 1 (hind wing) crossvein(s), posterior branches twice forked, few (if any) gradate veins; most more posterior veins forked; hind wing CuA long; veins and margins with long macrotrichia, membrane with dense microtrichia. Abdomen weak: small tergites and sternites and very large pleural regions; trichobothria on cercal callus of small ectoprocts (Fig. 29). Female: tergite IX laterally extended; pair of fused lateral gonapophyses present. Male: pair of elaborate appendages (?entoprocessus), ectoprocts very small; gonarcus, parameres and hypandrium internum distinct. A small widely distributed family containing about 30 species. The genera are closely related. Sisyra is cosmopolitan, Climacia is New World, and other small genera include Sisyrella, Sisyrina. (.Parfin & Gurney 1956, Monserrat 1977).

19

fined raised tubercles; antennae filiform in female, strongly unipectinate in male (Figs. 30, 32); mouthparts strongly reduced, sometimes scarcely protruding. Prothorax at least as wide as long, usually broader; pterothorax broad. Legs cursorial. Wings subequal, very hairy, membrane sometimes mottled (Fig. 31); wing shapes and relative sizes sexually dimorphic: fore wing of male relatively broader and shorter than that of female, hind wing sometimes broader than fore wing in male, usually narrower in female. Venation (Fig. 31): fore wing costal space usually narrow, recurrent humeral vein absent; costal crossveins usually simple, occasionally a few forked; pterostigma not defined; trichosors present; R j and Rs separate to wing margin; Rs linked to R j by 1 - 3 crossveins; Rs with 2 - 5 branches, with few (if any) crossveins, sometimes arranged in single gradate series; M A arising separately, from stem of R j + Rs or from Rs, usually forked (Fig. 33); M P deeply forked or 'twigged' near wing margin. Abdomen short, moderately stout. Female: ectoproct small with cercal callus; tergite IX deep, extending to ventral side of insect; tergite VIII not incorporating spiracle; sternite VIII often reduced; lateral gonapophyses extended to form long ovipositor extending for several mm, membranously connected ventrally; stylus absent; posterior gonapophyses short; 2 globular spermathecae sometimes associated with pouch like bursa. Male: ectoproct transverse, cercal callus defined, often with hooked posterior and dorsal lobes, (Nallachiinae), or reduced with compensating enlargement of tergite IX (Dilarinae); tergite IX deep; tergite VIII not incorporating spiracle; gonarcus arched; 2 long mediuncus lobes, flanking median sclerite in Nallachiinae, slender; parameres long and slender; hypandrium internum small. A b o u t 40 species in 2 subfamilies: 1 Fore wing vein M A arising as a branch from

Family Dilaridae Small delicate lacewings, fore wing length ca 4 - 1 2 m m . Eyes large; ocelli represented by de-

Fig. 30. Dilaridae. Pectinate antenna of male of Nallachius krooni (Minter 1986).

20

Planipennia (Lacewings)

Rs; male antennae never with more than 3 apical segments lacking lateral process Nallachiinae

-

Fore wing vein MA separating from R stem before separation of R, and Rs, rarely more distinctly separate at wing base; male antennae with several apical antennal segments lacking lateral process Dilarinae

Dilarinae occur in the Old World, predominantly in the Palaearctic, and Nallachiinae are New World except for the anomalous Nallachius krooni from southern Africa. Dilarinae include Dilar, Rexavius, Berothella, and Nallachiinae include only Nallachius. The family is absent from the Australian region (Navas 1909; Carpenter 1940, 1947; Adams 1970). Family Polystoechotidae

Fig. 31. Dilaridae. Wings of Nallachius 1986).

krooni

(Minter

Large sturdy lacewings, fore wing length ca 15-40 mm. Eyes small to moderately large; antennae filiform, less than half fore wing length; ocelli absent; mandibles sturdy. Pro thorax short and broad; pterothorax broad; abdomen stout or

Fig. 33. Evolution of fore wing anterior media in Dilaridae: A, MA is a free branch of media, connected only by a crossvein to the radial system (Rexavius marmoratus)-, B, M A bends upwards to contact R (b = basal part of MA), as most Dilarinae; C, MA appears as branch of Rs, as most Nallachiinae (Adams 1970).

21

Systematic account

Fig. 34. Wings of Polystoechotidae: Polystoechotes

puncta-

lus (Carpenter 1940).

slender. Legs cursorial, relatively long. Wings subequal (Fig. 34), fore wing slightly longer than hind wing; recurrent humeral vein present; costal area slightly to moderately broadened; costal veins forked (fore wing) or simple (hind wing), sometimes interlinked near base of wing; Sc and R[ fused distally; pterostigma poorly defined; trichosors present; usually a basal Sc-R crossvein; Rs + M A separates from R, near base of wing, with 7 - 1 5 branches all forked repeatedly; Rs linked to R ! by few (c. 2 - 8 ) crossveins; M A separates from Rs near base; 2 sets of gradate veins in each wing; CuA forked near base of wing. Ectoproct with cercal callus and trichobothria. Female: tergite IX ventrally extended, sometimes subtending ectoproct; tergite VIII deep, incorporating spiracle VIII; sternite IX simple or divided, if undivided, with dorsolateral and ventral median lobes; spermatheca slender; subgenitale defined. Male: tergite IX small and short, sternite VIII large; sternite IX trifúrcate or simply forked; internal armature complex - gonarcus sometimes incomplete dorsally, apparent arcessus broad and long; entoprocessus slender; parameres forked, with a median T-shaped sclerite.

Fore wing costal space narrow, crossveins throughout its length, some usually forked: if more confined to basal region of cell, some (at least) always forked; humeral vein simple; Sc and R t distinct to wing margin; a basal and a distal ScR crossvein; R , and Rs separate near base of wing, Rs with 3 branches interconnected by 2 series of gradate veins. Hind wing vein Cu runs parallel to wing margin for considerable distance, with numerous branches. Abdomen moderately sclerotised, with distinct tergites and sternites; ectoproct relatively small and rounded; cercal callus with trichobothria present. Female: sternite VIII forming large subgenital plate which can reflex ventrally to expose sclerotised areas in genital chamber; tergite IX ventrally and posteriorly extended; a pair of short gonapophyses laterales. Male: sternite IX with median posterior projection; gonarcus broad; mediuncus usually distinct, slightly hooked; lateral arms of genitalia with strong digitate or spined processes. Neurorthidae contains only about 10 species, distributed amongst 3 geographically discrete (and very closely related) genera. Neurorthus is from southern Europe and North Africa, Nip-

A small family, comprising 3 monotypic genera in the New World. Polystoechotes. is widely distributed (Nearctic-Chile), Platystoechotes occurs in California, Fontecilla in Chile. The genera are separated on venation, and Carpenter (1940) was not able to reconcile genitalic homologies between Polystoechotes and Platystoechotes. Family Neurorthidae Small delicate lacewings, fore wing length 6 - 1 0 mm. Head short and rounded, ocelli absent; antennae filiform to moniliform, shorter than fore wing; mouth parts as Sisyridae. Pronotum short, broad. Pterothorax large. Legs slender. Wings subequal (Fig. 35), elongate oval, apically rounded; nygmata present; trichosors present.

Fig. 35. Neurorthidae: wing venation of

(.Riek 1970).

Austroneurorthus.

22

Planipennia (Lacewings)

poneurorthus is known from Taiwan and Japan, and Austroneurorthus from Australia, (Nakahara 1958, Zwick 1967). Formerly included in Sisyridae, and raised to family status by Zwick (1967). Family Mantispidae Moderate to large lacewings with raptorial forelegs (Fig. 75), fore wing length c. 5 - 3 0 mm. Head rather small, vertex sometimes strongly domed; ocelli absent; eyes large; frons-vertex boundary usually obscure. Antennae short; scape large, bare or with black setae; flagellar segments simple to strongly broadened to discoidal. Mandibles long; maxillary palpi 5-segmented; labial palpi 3-segmented; ligula well developed. Prothorax usually greatly elongate, tubular, sometimes rugose and/or tuberculate. Pterothorax usually broader than prothorax. Legs: coxa I greatly elongate, femur laterally compressed with ventral spines, tibia arched with lateroventral ridges acting as 'scissors' along femoral spines when tibia closed on femur; other legs long, not elaborated; tarsi 5segmented, claws simple or bifid. Wings (Figs 36, 37) elongate, subequal, usually rather narrow and fore wing somewhat longer than hind wing, hyaline to brightly coloured, sometimes banded; fore wing occasionally slightly thickened; trichosors usually absent, rarely present near apex of wing; pterostigma well defined, usually dark. Costal crossveins few, simple; cell Sc sometimes almost obliterated before pterostigma, where Sc and C may be contiguous; Sc and R^ linked distally by short crossvein opposite pterostigma and 1 - 3 more basal crossveins; Sc and R j reach wing margin separately; Rs + M A separates from R t in basal third of wing, pectinate, with 1 major

series of gradate veins always present, and second (inner) series variously present, absent or sporadic, linked to R j by 2 or 3 crossveins; M A separates from Rs near base, pectinate; small jugal vein present; overall, venation rather 'open'. Abdomen well sclerotised, usually shorter than wings. Female: sternite VII sometimes modified, occasionally with excavated pouchlike structure ('crumena'); subgenitale distinct, well-developed, divided, or reduced lateral lobes sometimes present; tergite IX narrow, entire or apparently divided and with distinct ventral portion; gonapophyses laterales well-developed; ectoprocts always separate dorsally, with patch of short trichobothria; spermatheca complex and lobed. Male: sternite IX variable; ectoprocts usually distinct dorsally, cercal callus sometimes indistinct; gonarcus arched, apex variable; mediuncus distinct, with slender pseudopenis; parameres elongate, sometimes with setal bases apically; hypomeres sometimes present; hypandrium internum small. Two subfamilies have long been recognised, albeit sometimes with tribal status: Mantispinae and Platymantispinae, (the latter with tribes Platymantispini, Theristriini, Drepanicini), but the following scheme, based on a detailed phylogenetic study by Lambkin (1986 a, b) has now replaced this.

Key to 1

-

Fig. 36. Mantispidae: wing venation of Gerstaeckerella

subfamilies

Pronotum in 2 pieces: anterior piece dorsal only, posterior piece strongly extended and ventrally contiguous Symphrasinae Pronotum entire, tubular 2

irrorata, with all veins labelled (Poivre

1978).

23

Systematic account

2

3 -

Fore tarsus with single claw; anterolateral margins of mesoscutum acutely p r o d u c e d . . . Mantispinae Fore tarsus with 2 claws; anterolateral margins of mesoscutum rounded 3 Fore tarsus claws simple Drepanicinae Fore tarsus claws bifid . . . . Calomantispinae

Symphrasinae are limited to the New World and includes the genera Plega, Trichoscelia and Anchieta. Drepanicinae are a southern group, occurring in South America and Australia. Included genera: Drepanicus (including large green 'leaf-like' forms from Chile), Ditaxis, Theristria (the most diverse mantispid genus in Australia: 23 spp.), Gerstaeckerella. Calomantispinae. North America and eastern Australia. Included genera: Nolima (N. America), Calomantispa (including some brightly coloured Australian species). Mantispinae occur throughout the tropics and temperate regions and are the most diverse group of Mantispidae, with about 30 nominal genera. Representative genera are Campion, Climaciella, Mantispa, Sagitallata. See also Berothidae: Rhachiberothinae, which are anomalous and possibly annectant between Mantispidae and Berothidae.

Family Berothidae Delicate small to medium-sized lacewings, fore wing length c. 6 - 1 5 mm. Head capsule rounded; ocelli absent; face and mouthparts short to elongate; antennae moniliform, shorter than fore wing, scape often enlarged. Mandibles normal or reduced. Pronotum usually slightly longer than broad, generally narrower than pterothorax. Legs cursorial, rarely (Rhachiberothinae) forelegs raptorial (Fig. 75). Wings subequal, oval, narrow and strap-like, or falcate (Fig. 38); trichosors present; membrane hyaline or variously mottled with brown or grey; veins setose, occasionally (Spermophorella females) with broad scale-like setae on hind wing. Fore wing costal space narrow, many costal crossveins usually forked; humeral vein recurrent or simple; Sc and R[ distally fused at point or linked by short crossvein, one basal Sc-R crossvein; 2 or 3 R r R s crossveins; CuA very long, parallel with hind margin for much of wing length; CuP sometimes absent; very rarely with 'vesicae' on wings (Fig. 80). Abdomen with tergites and sternites clearly defined, 8 pairs of spiracles; ectoproct and tergite IX distinct (Fig. 88) (female) or closely associated (male); cercal callus distinct. Female: tergite VIII usually deep, sternite VII large or variously reduced; lateral gonapophyses simple or with long hypocauda; subgenitale large to strongly reduced, sometimes divided; postgenitale present or absent; spermatheca usually complex and coiled, sometimes with diverticula. Male (Fig. 39): gonarcus complete; gonocoxites fused with it throughout length or distally separated; mediuncus present, sometimes long, sometimes with pseudopenis at apex. Sexual dimorphism reflected in size of eyes, shape of head, length of antennae, presence of flattened vein setae. Berothidae are widely distributed, and 4 subfamilies are usually recognised, characterised fully by MacLeod & Adams (1967) Key to subfamilies 1 2

, A

CUP'CUA'

MP

MA

3

Fig. 37. Mantispidae: wing venation of (A) Campion sp., (B) Ditaxis sp. (Riek 1970).

Fore legs raptorial; free stem of MA in hind wing oblique Rhachiberothinae Fore legs cursorial; free stem of MA in hind wing vertical 2 Face elongated below eyes; abdominal tergite IX free from e c t o p r o c t . . . Cyrenoberothinae Face short; abdominal tergite IX fused with ectoproct 3 Fore wing: bases of R and M fused, with no trace of composite structure; MP diverging from Rs + MA at > 30° Nosybinae Fc re wing: bases of R and M usually separate; if adjacent or fused, some trace of separate origins present; M P diverging from Rs + MA at angle of usually < 2 0 ° Berothinae

24

Planipennia (Lacewings)

Fig. 38. Berothidae: wing venation Isoscelipteron tonkinense (Aspock Aspock 1980).

of &

Family Hemerobiidae

Fig. 39. Terminalia of Berothidae: male genitalia of Cyrenoberotha, lateral (gcx, gonocoxite; gs, gonarcus; hyi, hypandrium internum; mu, mediuncus) (MacLeod & Adams 1967).

Rhachiberothinae. Completely distinguished by raptorial fore legs. Contains 2 African genera, Rhachiberotha and Mucroberotha. Cyrenoberothinae. Contains only from Chile.

Cyrenoberotha,

Nosybinae ( = Sphaeroberothinae). Contains only the African Nosybus. Berothinae. By far the largest and most widely distributed subfamily, containing about 20 genera (representatives: Acroberotha, Berotha, Isoscelipteron, Lomamyia, Spermophorella, Stenobiella). Subfamily range includes Africa, Asia, Australia, southern Europe, North America.

Small to medium-sized lacewings, usually delicate-looking. Fore wing length c. 3 - 1 8 , most species 4 - 1 0 mm. Head small to medium; ocelli absent; antennae s'cndcr, moniliform, length c. half to slightly greater than fore wing length, scape enlarged, occasionally ornamented. Mandibles strong, pointed, with internal tooth; maxillary palpi long, 5 or 6 segmented; galea with basigalea and lacking apical knob; labial palpi 3 or 4-segmented. Pronotum usually short, commonly broader than long; mesonotum larger than metanotum. Legs cursorial, slender, tibiae sometimes slightly expanded, usually with short spurs; tarsal claws simple. Wings usually oval (Fig. 40) or elongate and subequal, rarely falcate, rarely with hind wing reduced or absent or fore wing short and coriaceous (Fig. 42); hyaline to strongly patterned; trichosors present; pterostigma usually distinct in both wings; Venation very variable: united by vein Rs in fore wing having > 1 (usually 2 - 4 ) branches from R t ; costal space variable, when broad the humeral vein usually recurrent, this otherwise simple; hind wing with single Rs; gradate veins variable, usually few series; fore wing with jugal lobe; hind wing with distinct frenulum. Abdomen cylindrical; tergites and sternites usually well-defined; cercal callus and trichobothria present; 8 pairs of spiracles (Fig. 41). Female: tergite IX broadened ventrally below ectoproct; tergite VIII extended ventrally; spiracle 8 in lateral part of tergite; gonapophyses laterales prominent, convex, sometimes with short apical stylus; subgenitale usually present; praegenitale rarely present; spermatheca simple, usually tubular or slightly coiled. Male: tergites I - V I I I simple, posterior tergites occasionally with posterior dorsal lobes; spiracle VIII in pleural mem-

Systematic account

25

Fig. 40. Hemerobiidae: fore wing venation of Micromus tasmaniae (New 1988b).

brane (except Notiobiella: in tergite); tergite IX sometimes fused with ectoproct, occasionally with long lateral process; sternite IX short, simple; ectoproct often elongated distally, sometimes with long ventral process(es), frequently with spines or thickened setae. Gonarcus transverse; arcessus distinct; entoprocessus sometimes present; parameres simple, free or fused; superprocessus present or absent; hypandrium internum small. Occasional sexual dimorphism in wing characters {Notiobiella viridis males have incrassate basal fore wing veins) or head (ornamentation of scape and vertex of males of Zachobiella pallida). Common name: brown lacewings. A cosmopolitan family containing more than 500 described species. Many genera are small and geographically restricted but a few (Hemerobius, Micromus) are diverse and widespread. Other representative genera are Notiobiella, Psectra, Wesmaelius, Sympherobius, Zachobiella. A separation of Notiobiella (as Notiobiellinae) from all others (Hemerobiinae) was suggested by Nakahara (1960), but this has not been generally adopted, and subfamily divisions are not used in the family. Likewise, an early separation of the forms having a 2-branched Rs in the fore wing as the family Sympherobiidae (Comstock, 1918) seems unnecessary. See also Tjeder (1961). Family Chrysopidae Medium to large lacewings, generally slender, fore wing length c. 6 - 3 5 mm. Head medium sized, short to rather long; ocelli absent; antennae filiform, length c 1 / 2 - 2 times fore wing length, scape usually enlarged, short whorled hairs on flagellar segments. Mandibles strong, acutely pointed, either symmetrical (with or without inner tooth) or asymmetrical (inner tooth on one mandible only); maxillary palpi 5-segmented, 2nd segment very short; galea with basigalea and small apical knob; labial palpi 3-segmented, ligula large. Pronotum well-defined, shape various, but usually about as wide as long or longer than wide; pterothorax broad. Legs slender, cursorial; tibiae

sometimes with short spur(s); tarsal claws simple or basally expanded. Wings (Fig. 43) large, subequal, narrow to rather broad, apex usually rounded, hind wing sometimes narrower than fore wing; usually hyaline or slightly tinted, sometimes with brown or black shading; much of venation usually pale green; pterostigma present, sometimes poorly defined; trichosors absent; small fore wing jugal lobe in Nothochrysinae, in which hind wing frenulum distinct. Fore wing costal area broad, humeral vein simple; costal crossveins simple, exceptionally forked or interlinked (some Apochrysinae); Sc and R , not anastomosing, usually linked by several distal crossveins; usually a single basal Sc-R crossvein (absent in Apochrysinae), occasionally several crossveins; Sc and R, rarely fused basal to pterostigma in hind wing (male of Mallada basalis and few related species); single Rs usually arising near base of wing, 'zigzagged' and with several branches linked by 2 (usually) or more series of gradate veins, a more irregular network of gradates in some Nothochrysinae, gradates rarely absent or reduced to few or 1 vein; intramedian cell (im) present in fore wing of most taxa; branches of M beyond im fuse to form Pseudomedia (Psm); Pseudocubitus (Psc) formed by fusion of CuA with branches of M; 3 anal veins present. Abdomen cylindrical, tergites and sternites usually well-defined. Female (Fig. 87): spiracle VIII usually in pleural membrane, rarely in tergite; tergite IX usually ventrally expanded and fused with ectoprocts; sternite VII sometimes posteriorly ornamented or excised; gonapophyses laterales usually large and conspicuous; subgenitale present; single large spermatheca with slender duct. Male (Figs 89, 90): spiracle VIII in pleural membrane; tergite IX distinct (some Nothochrysinae) or fused with ectoproct, commonly with strengthening apodeme and/or tapered anteroventrally; sternite VIII unmodified or (most Chrysopinae) fused with sternite IX to form compound sternite VIII + IX, often with lateral apodeme. Genitalia complex and variable: gonarcus arched or transverse; a subrectal transverse or arcuate tignum sometimes present above gonarcus; entoprocessus present or absent; arcessus present or absent; pseudopenis

26

Planipennia (Lacewings)

present or absent; sometimes a pair of elongate parameres (Italochrysa); tignum, gonarcus and pseudopenis on eversible 'sac' (gonosaccus), which is sometimes setose; gonapsis present or absent in dorsal membrane of sternite VIII + IX; hypandrium internum small, triangular, usually keeled.

tribe of Chrysopinae. See Adams (1967), Tjeder (1966), New (1980).

Sexual dimorphism sporadic: Meleoma males have tubercle between antennae; incrassation of basal fore wing veins and/or pterostigma in males of Mallada; atria of abdominal spiracles enlarged in males of some Glenochrysa, for examples. Common name: green lacewings.

-

Key to subfamilies 1

2

This almost cosmopolitan family is one of the largest in the Planipennia, with approximately 1900 species names published. Three Recent subfamilies are commonly recognised, although Apochrysinae is sometimes considered to be a

Jugal lobe of fore wing large, frenulum present on hind wing (Fig. 43 B ) . . . . Nothochrysinae Jugal lobe of fore wing and frenulum of hind wing reduced or absent 2 In fore wing, at least one of basal Sc-R crossvein and im cell present; space between Psm and Psc relatively wide (Fig. 43 C, D) .. Chrysopinae In fore wing, basal Sc-R crossvein and im cell absent; space between Psm and Psc relatively narrow (Fig. 43 A) Apochrysinae

Nothochrysinae. Considered to be the most primitive extant subfamily, with about 20 species in 7

Fig. 41. Terminalia of Hemerobiidac, Micromus timidus Hagen: A, apex of female abdomen, lateral; B, apex of male abdomen, lateral; C, genitalia, lateral (ar, arcessus; cpr, catoprocessus; ent, entoprocessus; gs, gonarcus; gl, lateral gonapophysis; hyi, hypandrium internum; lpv, lateral process of ectoproct unusual in Hemerobiidae) (Tjeder 1961).

2 mm Fig. 42. A brachypterous hemerobiid, Nusalala andinus, lateral aspect (Penny & Sturm 1984).

27

Systematic account

Fig. 43. Chrysopidae; A, Apochrysinae; B, Nothychrysinae: Dictyochrysa; Chrysopa s.l., to show wing venations.

genera occurring variously in Africa, Australia, Europe, North & South America. Representative genera: Dictyochrysa, Nothochrysa, Hypochrysodes. Apochrysinae. Contains the largest and most spectacular chrysopids, which were formerly considered to constitute a distinct family, Apochrysopidae. Ten small genera, with a total of about 25 described species in Africa, Australia, western Pacific and South America. Representative genera: Apochrysa, Oligochrysa, Nobilinus, Loyola. Chrysopinae. By far the largest group of Chrysopidae, containing about 60 putative genera or subgenera. Almost cosmopolitan, with many of the genera currently separated on small details of male genitalia and wing venation. Representative genera are Chrysopa, Eremochrysa, Leucochrysa,

C, Chrysopinae: Italochrysa; D, Chrysopinae:

Meleoma, with some others being considered variously as genera or subgenera of Chrysopa (examples Mallada (= Anisochrysa), Chrysocerca, Chrysoperla, Glenochrysa). Italochrysa are large robust taxa with a quadrangular im cell, and Ankylopteryx and allies have the basal fore wing costal space very broad. Anomalochrysa, an endemic Hawaiian genus, has 3 or more gradate series in the fore wing. Family Psychopsidae Large to very large lacewings with very broad wings and dense venation, fore wing length c 10-35 mm. Head short, often strongly reflexed ventrally under pronotum; eyes large; ocelli absent, but often raised setose areas in equivalent position. Antennae short, moniliform. Mandibles acutely pointed, with single internal tooth. Pro-

28

Planipennia (Lacewings)

Fig. 44. Psychopsidae: wing venation of Megapsychops illidgei, the largest Recent psychopsid (Tillyard 1919).

notum short, narrow; pterothorax broad, metanotum shorter than mesonotum. Legs short and slender, with pair of short apical spurs; tarsi with a pair of sharp claws, empodium broad. Wings broad (Figs 44, 45), apex broadly rounded, hind wing usually narrower and somewhat shorter than fore wing; small basal costal projection on each wing; no defined pterostigma; trichosors present; membrane frequently brightly coloured and spotted (Fig. 45), mottled or fasciated. Costal space broad, numerous costal crossveins, many branched; sometimes interconnected by full series of gradate veins; humeral vein weakly recurrent; veins Sc, R l 5 Rs strong, closely parallel to form 'vena triplica', interconnected by several crossveins, the 3 veins interlinked by strong crossveins at anastomosis c. 1/4-1/3 from wing apex; Rs with numerous parallel branches, with up to 3 series of gradate veins: the 'terminal series' continuing from the costal series, the 'discoidal series' behind the anastomosis of the vena triplica and the 'internal series' about half distance from wing base to discoidal series; additional irregular basal or central crossveins often present. Fore wing M with long stem, branches simple or anastomosing (Mi + 2 o r M 2 sometimes with M 3 ), most commonly with CuA ( M 3 + 4 or M 4 ); 3 anal veins. Veins, as body, often with long dense hairs; wing margin often long-haired, especially near tornus. Abdomen short, sturdy, spiracle VIII in ventrally prolonged tergite. Female (Fig. 46 A, B): abdomi-

nal apex enlarged, globular; tergite IX very large, ventrally prolonged to enclose large genital chamber, with fringe of long dense hairs, fused with ectoprocts: fusion sometimes indistinct, cercal callus and small trichobothria, apical margin often fringed with long hairs; tergite VIII narrow; subanale present; sternite VII with apex excised; gonapophyses laterales (enclosed in genital chamber) strongly setose at apex, dorsal lobe with long apically expanded setae, ventral stylus with thikkened spines. Subgenitale and postgenitale present; praegenitale often present; spermatheca a large membranous sac with or without lateral accessory glands. Male (Fig. 46 C, D): ectoproct with more distinct cercal callus and numerous trichobothria, apex often elongated; tergites VIII and IX slender, ventrally prolonged; sternite IX often substantially modified, with apical/lateral lobes, usually a strong lateral apodeme; subanale present; gonarcus a strong transverse arch; arcessus long, simple or apically bifid; entoprocessus present or absent; parameres apically fused in transverse arch; superprocessus present or absent; small hypandrium internum present. Common name: silky lacewings.

A small family, containing about 21 species, and with 3 major areas of distribution: southern Africa, the Oriental Region, and mainland Australia. No major infra-family groups are now

29

Systematic account

Fig. 45. Psychopsidae: A) Psychopsis dumigami (original).

(TiUyard 1922 c); B) Psychopsis

coelivagus\ C) Megapsychops

illidgei

Fig. 46. Terminalia of Psychopsidae: Silveira marshalli: A, apex of female abdomen, lateral; B, gonapophysis, lateral; C, apex of male abdomen, lateral; D, male genitalia, lateral (ap, apodeme; epr, ectoproct; gl, lateral gonapophysis; pop, postgenitale; sgp, subgenitale; st, stylus; ar, arcessus; gs, gonarcus; pa, paramere) (Tjeder 1960).

30

recognised (Tillyard 1919, Kimmins 1939, Tjeder 1969, New 1988 a) despite earlier suggestions (Navas 1916, Krüger 1922) that they exist. Included genera are Psychopsis (= Wernzia, Magallanes, Balmes) - the largest genus (14 spp), Australia and Orient; Megapsychops (1 very large sp., Australia); Cabralis, Nothopsychops, Silveira (all Africa).

Family Nymphidae Medium to large lacewings, wings slender to very broad, fore wing length 18 - > 40 mm. Head small to medium-sized; ocelli absent; eyes large; antennae filiform, usually 1/3-1/2 fore wing length. Thorax slender to moderately broad, pronotum usually narrower than pterothorax, often elongate. Legs moderately long, cursorial; tibiae with or without pair of short apical spurs. Wings subequal (Fig. 47); trichosors present; pterostigma well-defined; costal space slender to moderately broad; numerous costal crossveins, often forked, rarely interlinked, humeral vein simple; Sc and R j fused apically, one to many subcostal crossveins; Rs pectinate, with numerous irregular gradate veins and (usually) a well-defined outer gradate series; M A clearly arising from Rs in fore wing, more distinct basally in hind wing; position of M P fork variable; CuA (fore wing) or M P (hind wing) forked to enclose much of hind margin, numerous crossveins between pectinate branches; 3 anal veins distinct in fore wing, 1A sometimes less distinct in hind wing. Abdomen slender; ectoproct simple, cercal callus distinct; tergite IX often partially subtending ectoproct and sometimes closely associated with it. Female: tergite VIII deep; sternite VII shallow, variously elaborated at apex; gonapophyses laterales convex, arched, unornamented; subgenitale distinct; spermatheca usually slender. Male: sternite IX simple, rounded; tergite IX sometimes ventrally produced; gonarcus present, often partially divided medially; entoprocessus present or (usually) absent; arcessus present, sometimes large, may be ventrally ornamented or spined (hypocuspis); parameres present, sometimes spined or ornamented; gonapsis present or absent; hypandrium internum small.

About 25 species in 8 genera. The Nymphidae are almost entirely limited to Australia and New Guinea, with an unconfirmed record from the Philippines. Formerly considered as 2 distinct families, with the broad-winged genera lacking tibial spurs being referred to Myiodactylidae and the (presumably more advanced) narrow-winged genera with short tibial spurs to Nymphidae (Handlirsch 1906). Representative genera: Myiodactylus, Osmylops, Nymphes, Norfolius cNew 1981, 1984a).

Planipennia (Lacewings)

Family Myrmeleontidae Medium-sized to very large elongate lacewings, usually with wings rather slender, fore wing length c. 10 > 70 mm. Head moderately large, face not lengthened; eyes large; ocelli absent; antennae short, always less than half fore wing length, often considerably shorter, usually thickened or incipiently clubbed at or near apex; mandibles symmetrical, apical segment of labial palp often enlarged with sensory groove. Pronotum well sclerotised, often with transverse furrow, often longer than broad; mesonotum usually longer than metanotum. Legs slender to sturdy, short to long; tarsal claws simple or toothed, sometimes opposable on tarsus; femora sometimes with long setae, both femora and tibiae often spined; tibiae often with apical spurs. Wings subequal (Figs 48-52), elongate, usually slender and tapered, sometimes broadly rounded, rarely ± falcate; trichosors absent; pterostigma weakly defined. Costal area narrow; many costal crossveins, sometimes forked or interlinked; humeral vein simple; Sc and R, fused distally, usually no distinct basal crossvein; Rs and MA arise on common stem, usually few presectoral crossveins (often only 1 in hind wing); Rs with several branches, number of gradate veins variable, usually irregular, sometimes with branches bent to form almost straight line along centre of wing (anterior Banksian line); fore wing MP apparently simple, major fork in posterior half of wing formed from CuA, in hind wing major fork formed by MP 2 : posterior Banksian line sometimes present within these forks; CuP and 1A contiguous for much of length; 2 A and 3 A distinct, linked by crossvein or apparently fused along central length in fore wing. Hind wing of male sometimes with posterior basal knobbed setose projection (Fig. 77) ('pilula axilaris'), associated with glandular pocket on abdominal segment I. Abdomen elongate, sternite I strongly reduced so that sternite II below tergite I. Female (Fig. 53): ectoproct simple; tergites VIII and IX extended ventrally; spiracle VIII in tergite; gonapophyses laterales arched, rounded, these and ectoprocts sometimes with strongly thickened 'digging setae'; digitate or rounded posterior gonapophyses at inner basal margin of these, and central gonapophyseal plate; a median pregenital plate sometimes distinct near centre of border of sternite VII; spermatheca slender. Male (Fig. 53): tergite IX closely associated with ectoproct, latter simple or variously ornamented, sometimes strongly extended ventrally; spiracle VIII in pleural membrane; sternite IX small, usually rounded; gonarcus arched; mediuncus present, usually short; pair of short parameres; small hypandrium internum, usually indistinct. Common name: antlions.

Systematic account

31

One of the largest families of Planipennia, with about 2000 published specific names in several hundred genera. Cosmopolitan, although particular elements often geographically restricted. Higher classification in the family is problematical, and a large number (33) of tribes or subfamilies have been discussed by various workers (Markl 1954, Stange 1963, 1970, 1976, Holzel 1972, 1986, Aspock et at. 1980, Willmann 1977, Mansell 1985, inter al.). About 6 major groups have been treated as subfamilies in recent years, although their precise status remains uncertain and concensus on their integrity has sometimes not been reached (Mansell 1985). Stilbopteryginae were formerly considered to represent a distinct family (Stilbopterygidae) but are now believed to be true antlions (New 1982a).

Key to groups 1

-

2 3

-

Hind wing vein 1A with 5 or more branches; antennae short and strongly clubbed (Fig. 48) (very large species with narrow rounded wings) Stilbopteryginae Hind wing vein 1A with, at most, 3 or 4 branches, usually fewer; antennae, if short, not as abruptly clubbed or species smaller . . 2 Fore wing veins CuP and 1A distinct, not fused Palparinae (Palparini) Fore wing veins CuP and 1A fused soon beyond base 3 Hind wing M P running with 1A and 2 A parallel towards outer margin; CuAi without a distinct fork Ecthromyrmicinae Hind wing CuA with distinct fork; CuA 2 not parallel, converging towards the hind margin (Myrmeleontinae of some authors) 4

B Fig. 47. Nymphidae: A) Nymphes myrmeleonides; B) Osmylops (original).

32

4

-

5

-

Planipennia (Lacewings)

Femoral sense hair present on hind leg (generally large densely hairy species, fore wing costal cells usually interlinked, usually several presectoral crossveins in hind wing; legs short and sturdy; tarsal claws and tibial spines strongly arched, Fig. 52 C) Acanthaclisinae (Acanthaclisini) Femoral sense hair not present on hind leg (usually not densely hairy; if > 2 presectoral crossveins in hind wing, most fore wing costal cells simple [except, rarely, near pterostigma]; legs usually slender, claws and spurs various) (Myrmeleontinae of some authors) 5 Fore wing vein 2 A clearly separable from 1A at base; 2 A and 3 A linked by crossvein or meeting at a point Dendroleontinae (Dendroleontini) Fore wing vein 2 A close to 1A at base; 2 A and 3 A contiguous over central length Myrmeleontinae (Myrmeleontini)

Stilbopteryginae contains 2 genera (Stilbopteryx, Aeropteryx) with 9 species (Riek 1976) in Aus-

tralia. Formerly considered to be allied with Albardia (Ascalaphidae). Palparinae (or Palparini) are one of the most distinct segregates of antlions and have sometimes been separated from all others as 'Archaemyrmeleontidae'. Although long considered an archaic group, they may be specialised (Mansell 1985). Absent from Australia and South America, and predominant in tropical Africa. Many are large and spectacularly patterned species. Representative genera: Palpares, Tomatares, Crambomorphus, Pamexis. Echthromyrmicinae contains only Echthromyrmex, from Iraq, Afghanistan, Burma and Socotra (Holzel 1972) (treated as a tribe of Palparinae by Holzel 1986). Myrmeleontinae s.l. contains a wide array of antlions, some large groups of which are variously treated as subfamilies or tribes (as above), and is virtually cosmopolitan.

Fig. 48. Myrmeleontidae: Stilbopteryx

Fig. 49. Myrmeleontidae: Stilbopteryx,

sp. (original).

wing venation (Riek 1976).

Systematic account

33

Fig. 50. Fore wing base of (A) Brachynemurus and (B) Myrmeleon (Myrmeleontidae) to show relationships between veins 2A and 3A. (Stange 1970).

C, Fore wing of Crambomorphus (costal doubling) cf A; D, Hind wing of Palpares; E, Hind wing of Tricholeon; F, Hind wing of Myrmeleon; G, Hind wing of Creoleon. (ManseU 1985).

Myrmeleontinae s.str. (Myrmeleontini) contains Myrmeleon (Fig. 52 A) (the antlion), Hagenomyia and others. Dendroleontini (Fig. 52 B) is the predominant group in Australia, and includes a number of small genera. Acanthaclisini contains some of the largest and most sturdy species with more complex venation than many other groups. (Representative genera: Acanthaclisis, Heoclisis

(Fig. 52C), Centroclisis). Separation of these groups, and the host of smaller, sometimes poorly-defined, tribes has most commonly been predominantly on venation and leg characters, and it is likely that revisionary work incorporating a wider range of features will aid progress towards a more natural classifiaction of the family. Myrmeleontidae are most diverse in arid regions

34

Planipennia (Lacewings)

Fig. 52. Myrmeleontidae: A) Myrmeleontini, (Myrmeleon); B) Dendroleontini (Glenoleon); C) Acanthaclisinae (or Acanthaclisini) (Heoclisis).

Systematic account

Fig. 53. Terminalia of Myrmeleontidae: A, B, apex of female abdomen in lateral and ventral views; C, apex of male abdomen, lateral; D, male genitalia, lateral (ect, ectoproct; l.g., lateral gonapophysis; p.g., posterior gonapophysis; a. g., anterior gonapophysis; p, praegenitale; s, spermatheca; gen, genitalia; gon, gonarcus; med, mediuncus; par, parameres) (New 1985).

of Africa, Australia, Asia and the N e w World, but extend n o r t h w a r d s as f a r as C a n a d a a n d Finland, and south to New Zealand.

Family Ascalaphidae M e d i u m to very large, generally sturdy lacewings, fore wing length c. 1 5 - 6 0 mm. H e a d large, short;

35

ocelli absent; eyes very large, sometimes divided by horizontal sulcus; antennae short (rarely) to very long, usually at least half fore wing length, flagellum slender, apex with distinct short club; flagellum rarely sinuous or ornamented with long hairs in males; m o u t h p a r t s strong, mandibles pointed, palpi usually short. P r o n o t u m reduced, transverse; pterothorax enlarged, usually broader than prothorax, sometimes densely hairy. Legs short a n d sturdy, usually with strong setae/spines on f e m o r a a n d tibiae; tibiae with pair of apical spurs; tarsal claws strong, simple. Wings elongate (Fig. 54), subequal or hind wing broader than fore wing; trichosors absent; pterostigma usually welldefined, small, often dark; m e m b r a n e hyaline to brightly coloured or banded. Costal space narrow; costal crossveins simple, very rarely interconnected near pterostigma; Sc a n d R , fused apically generally lacking Sc crossveins; Rs a n d M A f r o m c o m m o n stem; Rs pectinate. Fore wing: m a j o r fork on hind margin formed f r o m CuA; m a j o r hind wing fork of M P 2 ; fore wing C u P a n d 1A distinct, in hind wing basally fused; anal angle of fore wing sometimes strongly angled or produced. A b d o m e n elongate, usually slender, rarely (Albardia) shorter a n d stout, male often with simple or furcate prominence on dorsum of tergite I, II, or III (Fig. 85), female a b d o m e n not ornamented. Female (Fig. 55): tergite IX usually slender; tergite VIII large, incorporating spiracle VIII; sternite VIII usually divided to f o r m ventral gonapophysis valves, rarely with distinct apical lobe (Albardia); lateral gonapophyses ('distivalvae') short, unornamented, usually not strongly setose; linguella (?modified apex of sternite VIII) present in m e m b r a n e beyond ventral valves; spermatheca small, tubular. Male (Fig. 55): tergite IX small; sternite IX usually simple, rarely (Albardia) elongated a n d furcate; spiracle VIII in pleural membrane; ectoprocts simple or forcepate; gonarcus elongate, apex with small lateral

Fig. 54. Wing venation of Ascalaphidae: Suhpalacsa dietrichiae (original).

36

Planipennia (Lacewings)

hooked parameres and median ventral pelta, lateral basal setose membranous lobes ('pulvini'); hypandrium internum small, inconspicuous. Common name: owl-flies. The Ascalaphidae are widely distributed in temperate and tropical regions, and contains about 400 species in some 65 genera, many of them raised on very small characters of venation, male abdominal ornamentation, or genitalia. Including the anomalous Albardia, 3 subfamilies are recognised. Key to subfamilies 1 2

-

Antennae very short, scarcely longer than head; abdomen sturdy Albardiinae Antennae longer, at least half length of fore wing 2 Eyes entire, not divided by horizontal sulcus Haplogleniinae (: Ascaloptynginae, Neuroptynginae) Eyes horizontally divided into 2 distinct regions by transverse sulcus . . Ascalaphinae

Albardiinae contains only Albardia furcata, an unusual species from tropical Brasil (New 1982 a). Formerly included in the composite family Stilbopterygidae. Ascalaphinae is the most widespread group, and includes a number of strikingly patterned diurnal forms (Libelloides) in Europe, as well as a range of more sombre taxa, many of which also have the hind wing broadened. It is the only group of Ascalaphidae in Australia. Representative genera: Ululodes, Helicomitus, Suhpalacsa. Haplogleniinae are often large, with wings relatively narrow. Representative genera: Haploglenius, Amoea. Monographed by van der Weele (1909); see also Henry 1972, Penny 1981, New 1984 c.

Family Nemopteridae Medium-sized to large lacewings, usually very slender and with hind wing greatly elongated, fore wing length 7 - 3 5 , hind wing length to c. 90 mm. Head moderately large, face often prolonged into slender rostrum, rarely short; ocelli absent; eyes large to very large; antennae filiform, occasionally thickened towards apex, short to longer than fore wing. Mandibles elongate or reduced, usually weak and sometimes immovable; other mouthparts variable in length, corresponding to extent of elongation of rostrum: maxillae very long in Crocinae, generally shorter in Nemopterinae, cardo short, stipes long, lacinia long and setose, galea simple or 2-segmented (basigalea then the longer), palpi usually apparently 4-segmented; maxilla may be variously reduced with (rarely) lacinia and galea absent and palpi vestigial; labium usually long, with 3-segmented palpi, rarely shorter with palpi 2-segmented. Pronotum elongate to short, usually slender; mesonotum large, broad; metanotum smaller, (shorter than in other Planipennia). Legs slender, length variable; fore coxae sometimes slightly elongated (Crocinae); tibiae often with apical spurs; claws long, slightly curved. Fore wing large (Figs 56, 57), variable in shape but usually broad; trichosors absent; pterostigma usually present, sometimes weakly defined; usually hyaline or fumose, sometimes strongly patterned with brown or yellow. Costal space narrow; subcostal crossveins simple, occasionally forked or interlinked; Sc and R, anastomosing below or slightly beyond pterostigma; Rs pectinate, with irregular but usually widely spaced gradates; M apparently not arising with Rs, although an oblique basal R - M crossvein present in some genera; major hind margin region included in fork of CuA, fork usually near base of wing; CuP and 1A distinct or fused for much of length; 3 anal veins in most Nemopterinae, 2 in Crocinae: 2 A and 3 A sometimes coalescing; males of some species of Crocinae with 'bulla' on hind margin. Hind wing long, basally

Fig. 55. Terminalia of Ascalaphidae: A, B, apex of female abdomen in latéral and ventral views; C, apex of maie abdomen, latéral; D, maie genitalia, latéral (ect, ectoproct; dv, distivalvae; vv, ventrovalvae; li, linguella; go, gonarcus; pa, paramere; pe, pelta; pv, pulvinus; g, gonosetae) (New 1984c).

narrow, always much (1.3 - > 3 times) longer than fore wing; threadlike (Crocinae) or broader and/or distally dilated (Nemopterinae), apex sometimes twisted through about 90° near apex; venation reduced: marginal veins (C anteriorly and 'ambient vein' (a. v.) posteriorly) strong; Sc present; R and M extending to, or near, apex; usually few R M crossveins, but many costal crossveins and M - a . v . crossveins; males of some Crocinae with strongly setose bulla in basal half of wing (Fig. 56). Abdomen cylindrical; spiracle I within tergite; tergite III usually long; cercal callus sometimes obliterated. Female (Fig. 58): tergite IX ventrally extended, sometimes subtending ectoproct; sternite VIII often distinct but medially divided, sometimes fused with lateral gonapophyses; lateral gonapophyses often large, never with stylus, occasionally with lower end elongated to form 'hypocauda'; spermatheca small, usually membranous. Male (Fig. 58): tergites V and VI sometimes modified to facilitate eversion of pleuritocavae; tergite IX usually divided dorsally, sometimes fused with ectoprocts; sternite IX

simple or variously elaborated; ectoprocts occasionally elongated. Gonarcus arched, transverse; arcessus present in Crocinae, mediuncus in Nemopterinae; gonosaccus (Crocinae) or gonolatus (Nemopterinae) present, setose; entoprocessus present in some Crocinae; parameres present, sometimes strongly lobed, fused in Nemopterinae to form common apex, sometimes with superprocessus. Sexual dimorphism may occur in head shape (males sometimes with larger eyes, female head sometimes broader), antennal length (longer in males) and form (flagellar segment and apex shape, number of segments greater in males), fore wing shape, bulla in males, degree of pilosity. Common names: thread-winged lacewings, spoon-winged lacewings. About 150 species, in some 40 genera divided among 2 subfamilies. Both occur in the tropics and warmer temperate regions, most abundantly in Africa, the Middle East and Australia, with

38

Planipennia (Lacewings)

representatives in southern Europe and the New World. Key to subfamilies 1 -

Hind wing filiform Crocinae Hind wing with apex distended, sometimes with 2 lobes Nemopterinae

Crocinae. Representative genera: Laurhervasia, Croce, Dielocroce, Austrocroce. Contains very delicate-looking small species, many confined to arid areas. Nemopterinae. Representative genera: Halter, Nemoptera, Palmipenna, Chasmoptera. Some European and African species are large and brightly coloured. Chasmoptera and Palmipenna have very broad brown hind wing dilations. (Tjeder 1967, various papers by Mansell 1980-1986).

Zoogeography and Distribution Planipennia occur throughout the tropical and temperate regions.

Fig. 57. Nemopteridae: Chasmoptera sp. (original).

Some families are extremely widely distributed, whereas others are very restricted, sometimes relict, and are sometimes highly characteristic elements of the faunas of particular zoogeographical regions. In the former, particular segregates, be they subfamilies, genera or 'species groups' tend to be much more restricted. As with many other groups of relatively poorly-known insects, assessment of detailed distribution patterns may need severe revision as the world fauna becomes better understood. There has been relatively little specialist collecting of Planipennia in many parts of the world and, whereas 'centres of origin' or 'centres of distribution' can usually be postulated, some caution is often needed in interpreting the fragmentary information available. The significance of 'absences' can only rarely be reliably appreciated without fuller collecting. One anomalous but apparently genuine case is the lack of Chrysopidae, which are otherwise cosmopolitan, from the main islands of New Zealand. There is no obvious reason why some of the relatively vagile and widely distributed chrysopid species of the western Pacific region should not have colonised New Zealand, even if no endemic forms evolved

C Fig. 58. Terminalia of Nemopteridae: Apocroce pusilla: A, apex of male abdomen, lateral; B, gonarcus and paramere, lateral; C, apex of female abdomen, lateral, (epr, ectoproct; gl, lateral gonapophysis; gs, gonarcus; mu, mediuncus; pa, paramere; 7 - 9 , tergites; V I I - I X , sternites) (Tjeder 1974).

Zoogeography and Distribution

39

With few exceptions, the distribution of Planipennia is considered 'natural', but there are a few undocumented introductions by man, and some attempts to extend distribution of some economically valuable predators of crop pests. Thus, the hemerobiid Micromus timidus was taken to Hawaii from Australia to help control sugar-cane pests (Williams 1927), and the recent spread of the Palaearctic coniopterygid Aleuropteryx juniperi in North America has been attributed to its inadvertent introduction and subsequent dispersal on nursery conifers (Wheeler 1981) and it was probably also introduced to Britain from continental Europe (Ward 1970). The two Coniopterygidae known from Hawaii are presumed adventive (Zimmermann 1957), and Cryptoscenea australiensis has been introduced to New Zealand from Australia (Kimmins & Wise 1962).

(Fontenelleini). All recognised major lines are restricted in distribution and probably monophyletic. In Fontenelleini one line (Cryptoscenea, Paraconis) occurs predominantly in the Australian region, with the closely related Neoconis and Pampoconis in western America. A second line (Spiloconis) is limited to Australia and south east Asia, and a more diverse third line is Holarctic and African. Coniocompsa is Palaeotropical, and Aleuropterygini includes Heteroconis in Australia and Asia, and Aleuropteryx in Africa and the Holarctic region. Meinander suggested that, as Pangaea separated, the Cryptoscenea-Neoconis group became isolated on the southern continents, and that subsequent glaciation possibly isolated the two groups in Australia and America. The Bornean Paraconis may be derived from a northwards - moving Australian ancestor. In America, Neoconis perhaps spread northwards around 30-40 x 106 years ago. As another example, Meinander considered that Heteroconis (Australian origin) and Aleuropteryx (Palaearctic origin) must have separated early, and the dispersal of one group of Aleuropteryx to South Africa probably occurred during the Tertiary. The A. loewii group is at present reasonably disjunct, in Europe and central/southern North America. Within Coniopteryginae, most subgenera or species groups of Coniopteryx are severely restricted in distribution - Metaconiopteryx, for example, to Europe and north west Africa.

The preceding 'Systematic Account' includes general comments on distribution of major groups, and some of these are amplified below. It is particularly difficult to marry the evidence from the fossil record with distribution of some Recent forms, other than to imply that the range of some families may have contracted markedly as a result of climatic change. But whereas, for example, the present distribution of Psychopsidae indicates their being a relict (gondwanan) family, the same cannot be claimed for Osmylidae (now absent from North America) or Mantispidae (now absent from Britain) and others which seem to have become more restricted in relatively recent times. A few families now show remarkably disjunct distributions - Ithonidae are almost entirely limited to Australia, where they are widespread, but Oliarces clara is North American.

Most other groups of Planipennia have not been subjected to as detailed an evolutionary appraisal, and reasons for present distribution can only be loosely inferred in relation to geological history and habitat characters, considered in relation to very limited collections. Whereas, for example, Mansell (1985) recognised two major geographical elements in the southern African Myrmeleontidae (a rich endemic fauna in the arid west, and an easterly fauna influenced by elements extending southwards from eastern and central Africa), a great number of taxa are still known only from single localities, and their precise distributional ranges are unknown. Many Australian Myrmeleontidae, for example, could well be much more widespread than at present known {New 1986 c). Precise distributions are known only for European and some North American taxa.

Analytical investigations of Planipennia distribution are few, and limited to few families. The taxonomically isolated Coniopterygidae clearly divided into Coniopteryginae and Aleuropteryginae early in their evolution, and both subfamilies are now widespread. Some distributional trends in this relatively well-studied group are now well-established (Meinander 1979, 1981). Aleuropteryginae are divisible into three welldefined tribes, two of which (Aleuropterygini, Coniocompsini) form a sister group to the third

Distributional information even on European taxa (Aspock et al. 1980) may be rather imprecise, but analyses of Palaearctic Myrmeleontidae (Holzel 1986 - showing several major centres of distribution) and North American Hemerobiidae (Klimaszewski & Kevan 1985 four major patterns: Holarctic and transcontinental, western Nearctic, disjunct Nearctic, eastern Nearctic; Fig. 60) exemplify the more reliable syntheses which are at present possible. For much of the rest of the world, distributions can only be inferred at

there, but even various (poorly documented) attempts to introduce Australian chrysopids appear to have failed. The absence of Myrmeleontidae: Palparinae from Australia and South America may indicate that the group evolved after separation of the southern continents: Mansell (1985) considered it highly unlikely that this predominant African subfamily could have entirely disappeared from the other major southern land masses. Similar anomalies occur in several other families, and have sometimes been emphasised by uncritical allocation of geographically disjunct taxa to the same higher group.

40

Planipennia (Lacewings)

disjunct temperate (Holzel 1984).

the species level from 'spot' samples, often at only one/few time(s) of the year. As more such samples are examined and integrated, it is becoming clearer that many species and species groups may be more widely distributed than hitherto supposed: the faunas of parts of New Guinea, the Philippines, peninsular Malaysia and the Indonesian archipelago, for example, have much in

common, with some elements occurring also on the Indian subcontinent. Some groups, though, are clearly circumscribed (Fig. 59). Rapismatidae are known only from the Oriental/south east Asia region, and are apparently most diverse in Malaysia. Most species are known from only single localities and very few

Zoogeography and Distribution

Fig. 60. Major distribution patterns of Nearctic Hemerobiidae: A, transcontinental e.g. Micromus montanus; B, western, e.g. M. variolosus; C, eastern, e.g. M. posticus; D, disjunct, e.g. Hemerobius ovalis (Kevan & Klimaszewski 1986).

individuals, and the known material of the 16 described species comprises only slightly more than 30 specimens. Nevertheless, the inferred distribution centre is probably realistic as these large spectacular insects would be likely to have been collected by nonspecialists (as have all the known individuals!). The same applies to Polystoechotidae, Nymphidae, Psychopsidae and other more conspicuous Planipennia. All Nymphidae known from outside Australia (New Guinea, ?Philippines) belong to the more primitive broad winged category (formerly Myiodactylidae), and, whereas they may have spread northwards from Australia, the narrower winged taxa have radiated within Australia. Psychopsidae have a recent distribution consistent with a 'southern'

origin. The African fauna is generally more diverse (at the generic level) than elsewhere, and shows clear differences from the Australian/Asian taxa. The Asian and Australian species are closely related. Neurorthidae also appear to have a disjunct distribution which is narrower than implied in the fossil record (Baltic amber). Larvae of the European and Australian genera are extraordinarily similar, implying a very close relationship. The subfamilies of Dilaridae and Berothidae are largely distinct geographically: whereas those of Dilaridae do not overlap, Berothinae are very widely distributed but with most genera restricted (Aspock 1986). The putative subfamilies of Osmy-

42

lidae are also predominantly limited in distribution, four of them to the southern continents. Nemopteridae: Crocinae are also mainly southern, and the faunas of Africa, South America and Australia are generically wholly distinct (Mansell 1986). Crocinae are absent from North America and much of the Palaearctic, and appear certain to have a gondwanan origin. The other families also exemplify the trend of generally high local endemism at the species and (usually) generic level, with relatively few genera being broadly distributed across major geographical regions. In Australia, for example, well over 9 0 % of the 623 known species (New 1988 c) are not known elsewhere and the remaining few tend to be shared with neighbouring land masses such as New Zealand, New Guinea or islands of the western Pacific. Few are more widespread, although the antlion Distoleon bistrigatus occurs over much of the Pacific, including Hawaii. Widely distributed genera occur in several families: Myrmeleon s.l., Micromus s.l., Hemerobius and Chrysopa s. 1. are examples. The latter reflects a taxonomic artefact, as a large number of Chrysopinae have been referred uncritically to 'Chrysopa' and a wide range of generically or subgenerically distinct taxa are there represented. Apochrysinae are absent from the Holarctic region. Some 'non-Chrysopa 1 taxa of Chrysopinae have undergone explosive radiation in various parts of the world: the Leucochrysa/Nodita complex in South America and Anomalochrysa in Hawaii are among the most dramatic examples, and 'species' are extremely difficult to diagnose accurately in these genera. A number of highly unusual Planipennia occur on islands. Some, such as flightless species of Micromus s.l. on Hawaii are closely related to more typical forms. Others, such as Conchopterella (another flightless hemerobiid) from the Juan Fernandez Islands, are taxonomically more isolated.

Ecology Habitats Planipennia are predominantly a terrestrial group, and many taxa are associated regularly with vegetation. Others are restricted to relatively bare or open areas, such as rocks or open sandy regions. Two small families (Sisyridae, Neurorthidae) have aquatic larvae, and some Osmylidae (especially Osmylinae, Kempyninae) regularly occur close to water, and their larvae may be semiaquatic. As with many other groups of insects, habitats are most clearly defined by larvae, as the

Planipennia (Lacewings)

vagility of adults may result in their casual presence in a wide spectrum of areas not suitable for establishment or breeding. The two aquatic families are specialised secondary invaders of fresh water. Neurorthidae are associated with flowing fresh-water streams, often with stony bottoms, and rivers. Sisyrid larvae are limited in distribution by that of their specific hosts, fresh water sponges and bryozoans, and their habitat range is entirely defined by these. They are often found in still water, but occur also in streams. Adults of both families are only rarely captured far from water, as are some Osmylidae. The european Osmylus fulvicephalus has semiaquatic larvae (Ward 1965) and kempynine larvae in Australia have been found amongst stones and litter along stream edges. With the possible exceptions of Rapismatidae (the early stages of which are unknown) and Polystoechotidae (for which only anecdotal evidence of larval habitat is available - Carpenter 1940), the remaining Planipennia have terrestrial larvae. Many Mantispidae are specialised 'parasites' of spider egg-sacs, and some Berothidae are commensals with termites, but larvae of other families are generally free living. Australian ithonid larvae are largely limited to subterranean habitats in sandy soils, often in more arid areas. Many Myrmeleontidae are also associated with arid/semiarid areas, but their larvae are generally more active predators: some move freely beneath the sand surface. Pit-dwelling forms are usually restricted to sheltered sites, so that the pits are persistent rather than being washed out at frequent intervals, and may be abundant, for example, under raised buildings in many parts of the tropics. The pit may be substantially modified from the simple 'cone' (Callistoleon: Mansell 1988). Other antlions also occur under rock overhangs, in small caves, or on rock surfaces, as do Nemopteridae: one species of the latter was described from larvae collected in the pyramids of Egypt. Yet other myrmeleontids are cortical, as are some Ascalaphidae, which may be camouflaged to resemble lichens or pieces of bark. Many larvae of Ascalaphidae and some Nymphidae are flattened and have long lateral processes which presumably aid shadow reduction as they lie in exposed situations on ground or vegetation. Some ground-dwelling larvae of these families become covered with debris, and occur in open forest environments. Subcortical forms on trees include Dilaridae (MacLeod & Spiegler 1961), (which may also frequent galleries of timber-boring insects) some Berothidae, and Psychopsidae. Larvae of the latter in Australia appear to be specialised subcortical forms largely limited to Eucalyptus. Some Osmylidae appear to combine subcortical retreats with more active roaming on bark surfaces to feed

43

Ecology Stage 2

Surface view

o

Fig. 61. Pit construction by larvae of the antlion Myrmeleon obscurus. Stage 1 (not shown) is when the larva comes to the sand surface and remains inactive for an indefinite period. The larva then moves backwards, as indicated (Youthed & Moran 1969a).

\furrow^

Sectional view

Time taken

^¡T ¡ifcl 3min

5min -3hr

3-10min

5-10min

(Stenosmylinae in Australia), although they are only rarely found exposed during the daytime. In general, information on habitat preferences of these families is fragmentary, and the above statements are extrapolations from few (sometimes single) documented examples. Much more information is available on Coniopterygidae, Hemerobiidae and Chrysopidae. The great majority of members of these families occur on vegetation, and considerable limitation or 'host plant specificity' may be present. The major habitat dichotomies are 1) between low growing vegetation and trees and 2) between conifers and broad leaved trees. Closely related species may sometimes appear to be limited to one or other discrete vegetation type - although the underlying causes of this are almost entirely unknown. Prey specificity or 'preference' is a likely major influence on habitat selection. As examples of such limitation, in Europe Coniopteryx tineiformis is almost entirely confined to deciduous trees and shrubs, Conwentzia pineticola to conifers and the closely related C. psociformis to broadleaved trees. In Hemerobiidae, some species of Micromus are limited to low vegetation (M. variegatus), others occur on all kinds of plants (M. tasmaniae in Australia), and others may be very specialised on particular kinds of trees (M. angulatus on conifers). Both European species of Wesmaelius s.str. are clearly associated with conifers and the chrysopids, C. abbreviata, C. commata and C. phyllochroma are found on low vegetation. There is thus a full range from 'generalist' to 'specialist' taxa in the breadth of habitat utilised by particular species. Texts such as Killington (1936-37) and Aspock et al. (1980) enumerate many examples in the European fauna. Comparative studies on the biology of the same species in different habitats, to assess their relative resource requirements and availability, are rare. There is some suggestion that dispersal potential of immature stages on evergreen and deciduous trees may differ (New 1968), and larvae of many species frequenting the latter move onto/under bark to overwinter or pupate (New 1967), a trait which prevents them being removed from the habitat by being attached to falling leaves. In

5-10 min

addition, 'microhabitat' preferences have scarcely been investigated. A recent study based on insecticide knock-down samples in southern England (Barnard et al. 1986) revealed the likelihood of irregular distribution within the canopy of oak trees. Hemerobius humulinus, Sympherobius pellucidus and Nothochrysa capitata were captured much more commonly close to the trunk than in the more distant canopy. Interestingly, as noted by those authors, these species are dark or mottled, in contrast to others more broadly distributed in the leafy canopy which tend to be pale. There is some indication that some tropical Coniopterygidae may be limited to upper canopy of forests (Murphy and Lee 1971, Singapore; Meinander and Penny 1982, Brazil). Feeding habits With few exceptions, Planipennia are predators as both larvae and adults, and some early accounts imply that this is the only feeding habit present in the group. Adults of such groups as Coniopterygidae, Hemerobiidae, Chrysopidae, and others may be found crawling amongst prey organisms (such as aphid colonies) and normally seek prey by walking. Some adult Mantispidae are apparently 'sit and wait' predators (Boyden 1984), and are commonly found on flowers. In contrast, rapidly-flying Ascalaphidae have been likened in appearance to dragon flies, and are aerial predators. There is little evidence of prey specificity for many groups of Planipennia, and prey range is limited predominantly by physical accessibility thus, Throne (1972) found that the hard body of a gall wasp enabled it to elude Mantispa interrupta. The waxy cuticle of aphids such as Brevicoryne brassicae causes rejection by some chrysopids (C. lanata: Ru et al. 1975) and aphid cornicle secretions may be effective against Sisyridae (Pupedis 1987). Myrmeleon larvae capture many kinds of prey which fall into their pits (Matsura 1986). Despite widespread adoption of predation in the Planipennia, larvae of Australian Ithonidae appear to feed on decaying subterranean vegetation, perhaps especially bark of eucalypts, and their mouthparts are very reduced (Gallard 1932).

44

Examination of gut contents of other families shows that adults of several families take vegetable food to varying extents. Some may be entirely casual, resulting from grooming activities or feeding on honeydew (Kokobu & Duelli 1986). Other examples undoubtedly represent more regular feeding associations, or the capacity for flexibility of food type. A large proportion (14/20 individuals) of Australian Kempyninae contained plant material in their guts (New 1983 d), this ranging from fungal hyphae to bark flakes and pollen and, if this is truly representative of their food spectrum, these Osmylidae appear to be amongst the most generalised feeders yet known in the Planipennia. Other specimens dissected contained arthropod remains. Sisyrid adults (Sisyra terminalis) are thought to ingest plant materials whilst they feed on honeydew as an adjunct to predation (Kokobu and Duelli 1983), and some species of this family forage for a wide range of plant and animal foods (Pupedis 1987). Pollen has been found in the guts of some american Brachynemurini (Myrmeleontidae) (Stange 1970). Some South African Nemopteridae have been observed feeding on flowers (Picker 1984, 1987), and pollen may be the major food of African Nemopteridae, as Tjeder (1967) recorded specimens of several genera of Nemopterinae containing large quantities of pollen, together with unidentifiable fragments of vegetation, but never insect remains. Mouthparts of some of these species seem to be too weak for capture of insect prey, and pollen feeders included both 'long-faced' and 'normal' taxa. Some African Crocinae also contained pollen. Coniopterygidae can produce eggs when fed solely on honey {Fleschner & Ricker 1953) and adults may take honeydew in addition to animal food (Withycombe 1924). The most specialised non-predatory feeding habit of adult Planipennia occurs in some Chrysopidae: Chrysopinae, in which members of genera such as Chrysoperla, Cunctochrysa, Mallada and Nineta are honeydew feeders and employ extracellular symbiotic yeasts (Torulopsis spp.) to aid digestion (Hagen et al. 1970). Yeasts are maintained in a fore-gut diverticulum with greatly enlarged tracheae presumed to provide for yeast metabolism, so that such glyciphagous chrysopids differ anatomically from predatory species. The yeasts could provide essential amino acids absent from honeydews and pollens (Hagen & Tassan 1972), and the dichotomy in feeding habits is reflected in some aspects of mandible and ligula structure of adult chrysopids (Ickert 1968, Carli Silvani 1971). Hypochrysodes and Pamochrysa are pollinovorous (Principi 1956, Tjeder 1966) and, for the most part, the division between carnivorous and glyciphagous Chrysopidae is firm (Principi & Canard 1984). The species complex currently masquerad-

Planipennia (Lacewings)

ing as Chrysoperla carnea, though, apparently includes aphidophagous forms (mohave) as well as glyciphagous taxa. Although some species can be maintained for a considerable period on honeydews and related foods, animal food is sometimes necessary for reproduction. Males of C. oculata can copulate successfully if fed on sugar and water alone, whereas females need aphid food in order to mate. Larvae of species which are nonpredatory as adults are, as far as is known, wholly predatory other than for casual or augmentary intake of honeydew or nectar. Planipennia therefore range from highly specialised to highly generalised polyphagous feeders, and dietary specialisation may be accompanied by elaborate specialised behaviour patterns and habitat restriction. The aquatic larvae of Sisyridae are highly specialised, and feed by piercing cells of freshwater sponges: they are amongst very few obligate predators of these animals. First instars swim actively to find food, and the larvae do not then usually leave the sponge unless the latter dies (.Parfin & Gurney 1956, Brown 1952, Old 1933, Needham 1909). The larvae may assume the colour of 'their' sponge, presumably reflecting ingestion of contents, and the limited data available suggest that sisyrids may not be particularly host species-specific (Poirrier & Arceneaux 1972). Larvae apparently normally feed by inserting one or other 'jaw' at any time, a habit shared with some other families with 'piercing' rather than 'clasping' jaws. Perhaps the most specialised terrestrial planipennian larvae are those of Berothidae, some of which are specific feeders on subterranean termites. Larvae of the north American Lomamyia latipennis are true termitophiles. The first instar larva directs the end of its abdomen at a termite and 'waves' it (Johnson & Hagen 1981). This results in immobilisation of the termites, within 1 - 3 minutes through effects of an allomone. The termite is completely paralysed within 2 - 5 minutes, although its heart may beat for up to 3 hours. The third instar releases sufficient allomone to obviate the need for precise application and does not 'wave' the abdomen: up to 6 termites may be killed at a time. Physical contact between the berothid and termite is not needed, other insects present are not affected by the chemical, and the larva is assured of an ample supply of motionless food. Larvae of a related species, L. hamata, are also obligate feeders on termites, but inject a neurotoxin to induce rapid paralysis of their prey (Brushwein 1987). Such obligate predator-prey relationships are exemplified also by some Mantispidae which are specialised 'parasites' of spider egg cases. The active first instar larva changes to a sedentary

Ecology

physogastric form once the host is reached (Brauer 1869, early accounts summarised by Lucchese 1956). Two distinct strategies are employed by triungulins to locate spider eggs (Redborg & MacLeod 1983). They may either 1) board a female spider before she lays and enter the egg sac as it is constructed or 2) directly penetrate an existing egg sac. Some species are obligate followers of one or other habit, whereas other mantispids are facultative boarders or penetrators. Thus, attempts by Redborg & MacLeod (1983) to rear Climaciella brunnea by isolating larvae in 'pseudosacs' containing theridiid spider eggs failed because the larvae merely climbed to the highest point of the sac and assumed a characteristic phoretic posture. Other larvae failed to enter egg sacs proffered, and in this species 'boarding' is an obligate part of normal development. Larvae of Mantispa uhleri feed on the female spider whilst being carried (Redborg 1982) and, if an immature female is boarded, an instar may be lost. M. uhleri is associated with eggs of Agelinidae (Agelenopsis spp.) and larvae can halt development of spider eggs within the sac (Redborg 1983), apparently by chemical means, thus enabling the larvae to feed on eggs which might otherwise have hatched (Redborg 1983, Redborg & MacLeod 1984). In contrast, species such as Campion australasiae (— Mantispa vittata) directly penetrate lycosid egg sacs (McKeown & Mincham 1948), and it seems that at least some such species may be relatively host-specific. Other mantispids (Symphrasis, Trichoscelia) may be obligate parasites in larval cells of Hymenoptera: Vespoidea in central and South America, but related forms appear to be less specific, as they have been found in noctuid moth cocoons (Woglum 1935), cells of megachilid bees (Parker & Stange 1965), cells of other bees (Linsley & MacSwain 1955) or with scarabaeid beetle pupae (Werner & Butler 1965). Some of these may, therefore, be generalist predators (MacLeod & Redborg 1982), and larvae of Plega produce an adhesive secretion enabling them to stick to their food supply and remain largely immobile for much of their developmental period. In contrast, Nolima pinal larvae are active and may attack several individual prey. Some nemopterid larvae because of their slow approach to prey and slow insertion of mouthparts, are thought likely to be scavengers (Laurhervasia: Mansell 1976; Klugina: Hafez & El Moursy 1964). In contrast to the highly active larvae of some other families, these appear to be 'furtive predators'. Larvae of other families are generally believed to take whatever prey organisms are available, but methods and 'strategies' of prey capture and utilisation are varied. Larvae range from active pursuers of prey (exemplified by Coniopterygidae, Hemerobiidae, Chrysopidae) to sedentary am-

45

bush predators (many Myrmeleontoidea). Osmylus fulvicephalus probes wet mud to feed on larval Díptera and other denizens (Ward 1965) but most other families predominantly take exposed prey (Kawashima 1957, New 1974, Gallard 1922) and are apparently relative generalists, as far as is known. However, although it is known that many active planipennian larvae accept a wide range of prey, the relative suitability of different prey to particular predator species has only rarely been studied. Habitat specificity may often reflect prey specificity or 'preferences', and most work has been on the economically important families Coniopterygidae, Hemerobiidae and (especially) Chrysopidae. Cannibalism is probably quite common and has been recorded in such disparate families as Chrysopidae and Myrmeleontidae. Cannibalism of first instars could be adaptive under conditions of prey scarcity, especially between siblings such as larvae from the same batch of chrysopid eggs (Duelli 1981, 1984). Most planipennian larvae are solitary, other than for primary aggregations from batched eggs. Young aggregated ascalaphid larvae are apparently not cannibalistic and could communally attack a single prey organism (Tillyard 1926), but this habit has neither been confirmed nor noted elsewhere in the order. Prey seems to be discovered initially by random movement, and physical contact is often necessary for prey perception (Principi 1940, Arzet 1973, Bond 1980), although C. carnea larvae may be able to use chemicals emitted from honeydew of coccids to locate their prey up to 50 mm away (Kamechi 1932). Searching behaviour is discussed by Fleschner (1950), Bansch (1964), Butler & May (1971) and Bond (1980), and a synthesis of the extensive data on Chrysopidae (Canard & Duelli 1984) emphasises the likely generality of searching patterns. Intensive searching by C. carnea is stimulated by prey contact and involves a reduction of velocity, an increase of turning rate and in width of the search path. Searching, even by small larvae, can be extensive. A first instar Conwentzia pineticola can survive for more than 10 hours without feeding, and travel more than 40 m (Fleschner 1950). Coniopterygid larvae move actively and some feed most extensively on mites (Collyer 1952, Castellari 1980), although others cannot develop on (citrus) mites alone (Fleschner & Ricker 1953). Hemerobiid larvae also tend to be active, and may also consume several hundred small arthropods (such as aphids, mites, scales) during development. Larvae of some genera are somewhat physogastric, and these tend to be less active. Chrysopid larvae are divisible into 2 major categories: 1) slender active larvae (Chrysoperla, Niñeta, Anomalochrysa) which are largely bare and 2) stout debris-covered hairy larvae (Mallada, Nothochrysa) which often move more slowly

46

and are sometimes extremely well-camouflaged, as debris can include prey remains. Both groups are highly voracious and the range of prey recorded is very wide (Balduf 1939, New 1975, Principi & Canard 1984). Strict prey specificity in Chrysopidae is known only for Italochrysa italica which feed on early stages of Crematogaster ants {Principi 1946) and in Chrysopa slossonae which eats only the woolly alder aphid in North America (Tauber & Tauber 1987a), although other cases have been inferred. Zimmerman (1957), for example, commented that the likely predominant prey for Anomalochrysa in Hawaii (where aphids are naturally absent) may be Psocoptera. As Principi & Canard (1984) emphasise, prey diversity based on field records may not reflect the 'true' (optimal, usual, or preferred) prey of various species, as tests to determine prey effects on larval growth and survival, and subsequent adult fecundity and longevity have usually not been undertaken. Chrysopa perla larvae fed singly and monophagously with various species of aphids produce cocoons of very different weights (Ferran, in Principi & Canard 1984). Other species show developmental abnormalities with particular prey: Chrysoperla rufilabris fed on Drosophila adults fail to spin cocoons (Hydorn & Whitcomb 1979), C. perla fed on Macrosiphum rosae die as pupae within the cocoon (Canard 1973). Some prey are thus clearly unsuitable, even though accepted, and some influences of food are subtle: C. perla males fed entirely on Megoura viciae as larvae are sterile (Canard 1970). Mallada prasina larvae display a feeding specificity induced by their first meals: thereafter they cannot change diet, and may die if the kind of food is changed (.Babrikova 1979). Quantities of prey consumed are not precisely known, being usually estimated from 'numbers killed', and are difficult to measure accurately. Digestive efficiency of two species of Australian Hemerobiidae (New 1984 b) indicated possible differences between 'relative generalist' and 'relative specialist' species, in that specialisation may be reflected in more efficient use of that food. Pit-dwelling ant lion larvae have long attracted attention as 'ambush predators' (Wheeler 1930) but this habit is restricted, even in Myrmeleontidae, and occurs (as far as is known) only in Myrmeleon and related genera, some of which are very widely distributed. Others range from freeliving larvae which may remain motionless for long periods (Navasoleon on rock ceilings in Peru: Miller & Stange 1985; Dendroleon jezoensis in Japan: Baba & Edashige 1954) or actively pursue prey on sand surfaces (Acanthaclisis baetica in Europe: Principi 1947, Steffan 1971). Many of the latter category pass the day buried with their jaws agape (Neuroleon: Steffan 1971) and emerge only at night. Still others actively pursue prey under the sand (Vella: Stange 1970). Younger larvae of

Planipennia (Lacewings)

Myrmecaelurus trigrammus make pits, but older larvae live freely under or (more rarely) on the sand (Popov 1984). Pit-formers can usually move only backwards, and more active myrmeleontid larvae predominantly move forwards, a dichotomy recognised by Redtenbacher (1884). 'Sandflipping', in which larvae throw loose sand when potential prey enter the pits, often causing small sand-slides and hampering the prey's attempts to escape, may be an integral part of 'pit-operation' (M. immaculatus: Heinrich & Heinrich 1984). Mechanics of pit construction, and the ecology of their dispersion and use, has been extensively documented in several parts of the world (summary in New 1986 a), and the systems have been used to interpret more general aspects of predation and food utilisation. Pit-forming is associated with low energy expenditure for prey capture (Lucas 1985 a, b), and construction of pits only during cooler parts of the day (Youthed & Moran 1969a-c) may help to save energy, as well as to facilitate capture of nocturnal prey. A detailed comparative study of two African species (Griffiths 1980-82, 1985, 1986) in Sierra Leone exemplifies some of the subtleties involved. First instars of Morter obscurus had a higher rate of capture success than later stages, but were limited to small prey, with a low maximum size of prey which could invariably be captured. The major energy expediture for instars I and II was on predation, whereas the last instar spent relatively more on pit maintenance. First and last instars were especially vulnerable stages in development the latter because of the relative scarcity of large prey items. Small larvae of Macroleon quinquemaculatus construct steeper-walled pits than third instar larvae and always caught and consumed small ants (Pheidole) whereas larger larvae fed intermittently and became increasingly selective as they grew larger. 'Consistent feeders', 'inconsistent feeders' and 'starved larvae' had different growth rates, and inconsistent feeders actually had a greater weight loss than starved larvae of the same size: Griffiths (1981) tentatively suggested that hunger lowers the feeding threshold sufficiently for the predator to attack unsuitable prey. Physical determinants of pit construction include soil particle size (Lucas 1982, Allen & Croft 1985) and soil temperature (affecting both activity and pit size: Youthed & Moran 1969 a), and the physical course of pit excavation has been studied in Europe (Bongers & Koch 1981, Geiler 1965), North America (Tusculesku et al. 1975, Turner 1915, Green 1955, Haub 1942), South Africa (Youthed & Moran 1969a-c) and Australia (Kitching 1984). The process seems to be fairly general (Fig. 61), although an additional pattern of direct digging was noted by Turner (1915). The spatial distribution of pits has also received considerable attention, together with optimal pit

Ecology

size. Pit diameter reflects 'searching' capacity, prey size range and capture success of optimalsized prey (Wilson 1974). Increased encounter rate of prey, reflected in presence of larger pits can lead to 1) increase in rate of prey ingestion, 2) reduction in handling time and 3) change in proportion of each individual prey eaten (Lucas 1985). Prey capture is influenced by tufts of long thoracic hairs on the larvae (Le Faucheux 1972, Devetak 1985), helping larvae to detect prey by substrate vibrations. These hairs apparently influence 'targetting' by larvae, and energetic prey which escape the initial attack may be deterred from climbing out of the pit by the larva throwing sand. Energetic defence may be countered by dragging prey under the sand (Lucas & Brockmann 1982). Pit dispersion is determined by soil moisture and temperature, local topographic features such as stones (,Simberloff et al. 1968), and exposure (Klein 1982), as well as being substantially influenced by the density of neighbours (Morisita 1954, McLure 1976, Wilson 1974).

Life histories and voltinism The following paragraphs are to complement later sections on dormancy and reproduction, and provide a brief ecological overview. Duration of development in Planipennia lasts from a few weeks to a few years, with most species undergoing at least one complete generation each year. Many temperate region species have several generations during a limited part of the year, with a well-defined phenological break - usually accompanied by a period of dormancy - during winter. Taxa with development lasting more than one year appear to be unusual. Stilbopteryginae may be amongst the longest lived Planipennia: Aeropteryx linearis took 6 years to complete development (McFarland, in Riek 1974 b), but it is not usually clear to what extent captivity 'stresses' larvae and protracts their normal development by providing unusual prey or living regimes. Another antlion, Hagenomyia micans, is semivoltine in Japan (Furunishi & Masaki 1982), with a third winter occasionally being passed as larvae. Myrmecaelurus trigrammus also normally develops in 2 years, but extension of the intra-cocoon phase may result in a 3-year development (Popov 1984), and such plasticity may be more common than implied in the fragmentary literature. Irregularity of food supply may affect development time. Laurhervasia (Nemopteridae) larvae, for example, take 2 - 3 years to develop, depending on food availability (Mansell 1976) and starvation may protract duration of chrysopid larvae. Australian Ithonidae are thought to have a usual larval life of 2 - 3 years, but the data are inconclusive. Some temperate region Coniopterygidae, Hemerobiidae and Chrysopidae are consistently univoltine, bivoltine, or facultatively multivoltine with

47

several more or less continually overlapping generations during the warmer part of the year. Canard & Prìncipi (1984) emphasise the difficulty of interpreting clear voltinism patterns because of protracted oviposition and substantial adult longevity, and suggest 4 main kinds of seasonal development in Chrysopidae: 1) strictly univoltine, ranging from species with a short period of adult incidence (Nothochrysa californica only in April and May: Toschi, 1965) to adults being present for much of the season (Nineta flava from April to October, but see p. 89); 2) Univoltinism in more commonly multivoltine species, influenced by local climatic conditions (Chrysopa perla above about 650 m in Austria: Gepp 1975) or genetic variation (obligate voltinism in 7 0 - 8 0 % of a southern France population of C. perla in which at least 3 generations are otherwise usual: Canard 1973); 3) Facultative multivoltinism, a common pattern in climatically variable areas, reflecting the balance between temperatures adequate for development and conditions inducing dormancy (Latitude is an important factor for widely distributed species, in affecting the duration of the 'favourable period'. C. abbreviata is partially bivoltine in central Europe but has 4 generations annually in Bulgaria (Babrikova 1981)); 4) Continuous breeding, without dormancy. Inheritance of life history traits, and their interaction with food supply is complex in Chrysopidae (Tauber & Tauber 1987a, 1987b). The usual overwintering stage for the above families is as a prepupa (more rarely, a pupa) within the cocoon. Rarely, adults overwinter, as in C. carnea (which then undergoes a well-defined colour change from green to brown at onset of diapause: p. 89). Freeliving larvae overwinter in some Anisochrysa (or Mallada) spp., and may be relatively active and feed facultatively ( M . flavifrons: Principi et al. 1975), although fasting also occurs (Lacroix 1922). Aestivation patterns in hot dry climates are poorly understood. Likewise, seasonal incidence of Planipennia in the tropics has scarcely been investigated. There is some suggestion that adult mantispids may emerge over more of the year than some other families, perhaps reflecting the unpredictability of finding hosts at any particular time. Thus, Opler (1981) found Climaciella brunnea emerging continuously from August (middle of wet season) to February (early dry season) in Costa Rica, with a peak in September-November. In Australia (not tropics) Campion autralasiae numbers peaked in April, but adults occurred in most months of the year (McKeown & Mincham 1948).

48

Dispersal Suction traps and/or light trap catches in many parts of the world regularly include numbers of Planipennia, and adults of many taxa are clearly vagile. The ecological interpretation of such catches is usually difficult, as they reflect many different environmental factors (Bowden 1981, Zeleny 1984). Most Planipennia are generally assumed to be rather feeble fliers, although some (especially Ascalaphidae) are strong fliers which have been recorded 'patrolling' from fixed points. One individual of the Australian Megacmonotus magnus marked by Matthews (1947) was repeatedly captured and released up to about 135 m from its original station, to which it returned, and individuals frequented the same spot over several evenings. Other Ascalaphidae (Ululodes) have a rapid meandering flight, frequent changes in course, lateral darting and sometimes hovering (.MacLeod 1962, Henry 1977). Most Planipennia apparently do not undertake long distance flights, but only relatively trivial dispersal within their normal habitats. Planktonic effects may sporadically cause longer dispersal, and unusual incidences include a high proportion of Sisyra

Planipennia (Lacewings)

fuscata in aerial drift in Norway (Anderson & Greve 1975) and catches in ship nets in the North Sea (Hardy & Cheng 1986). Lacewings have been captured in airplane nets up to 1500 m above ground (Click 1939). Most flight appears to be solitary, but there are isolated records of 'swarming': Coniopteryx tineiformis in Britain (Southwood 1957), Ithonidae in Australia (Tillyard 1922, Riek 1974 a), Polystoechotes punctatus in North America (Fyles 1903), Hagenomyia tristis in Africa (Balfour-Browne 1956). Both sexes of Hagenomyia were present, but males are by far the more abundant sex in swarms of Ithone fusca and Megalithone tillyardi. Mass flights of Ithonidae reflect mass emergences, and may aid escape from predators (p. 50). Polystoechotes also flies in dense clouds, the function of which is unknown. More extensive, migratory, flight occurs in C. carnea, and perhaps other taxa - as light trap catches often contain habitat specific taxa displaced considerable distances from their nearest habitat. C. carnea undergoes seasonal migrations to and from overwintering retreats, but also relatively extensive flight during the major breeding season. Loss of flight activity during winter

Fig. 62. Flight activity patterns of Chrysopidae. Examples of the four distinct types of flight periodicity so far clarified. The top graph indicates the intensity curve of natural dayflight in the cages (Duelli 1986).

49

Dispersal

seems to be photoperiodically controlled (Bowden 1979). Otherwise, Duelli (1984) recognised 3 major types of flight by C. carnea in California: 1) appetitive downwind flight: straight downwind flight, normally undertaken by sexually mature individuals at l - 5 m above vegetation, which land when a scent plume from a food source is entered; 2) appetitive upwind flight: after the above, take off again and fly upwind in short 'hops' to approach food source. Then short inter-plant flights to locate food; 3) migration. Obligatory take off into the wind after teneral period and at a critical light intensity towards night. Individuals usually fly higher than on appetitive flights. Duelli (1980) noted an average migration distance of 40 km during the first 2 nights for a preoviposition female. Flight periodicity may also be well-defined, so that many lacewings are classed (at least anecdotally) as 'nocturnal', 'diurnal' or 'crepuscular', but few taxa have been examined in detail. Most instances rely on inferences from trap catches (New & Haddow 1971, on African Mantispidae) rather than direct observations of activity. Duelli (1984,1986) found 4 distinct activity patterns for Chrysopidae (Fig. 62): 1) most species examined resemble C. carnea in starting flight after sunset and ending before sunrise; 2) C. perla flies in late afternoon and finishes soon after onset of darkness; 3) Mallada basalis has dusk and dawn flight peaks; 4) Hypochrysodes elegans is diurnal and predominantly ceases to fly before sunset. Many chrysopids, therefore, appear to fly at night, and light trap catches strongly imply that this is so also for other families (e.g. Fig.63). Mantispidae, Myrmeleontidae, Ascalaphidae and Nemopte-

ridae, at least, contain both nocturnal and diurnal taxa. Many diurnal forms are brightly coloured (Palpares, Libelloides) and some mantispids are putative mimics of social Hymenoptera - sometimes involving substantial polymorphism (Climaciella brunnea: Opler 1981). Some highly active diurnal Nemopteridae, flying in bright sunlight, probably incorporate their wing patterns in a visual communication system (Knersvlaktia in S. Africa: Picker 1984). A combination of'semaphore signalling' and enhanced aerodynamic efficiency may occur in males of Palmipenna aeoleoptera whilst they glide to attract mates (Picker 1987). The broad dark hind wing flanges of Chasmoptera (Western Australia) probably help to disrupt predators (Koch 1967). In contrast, many nocturnal Planipennia are drab-coloured, or have translucent wings, and are cryptic when at rest. Dispersal by human agency has also occurred occasionally. In addition to range extensions noted on p. 39, occasional 'accidents' may involve transfer to areas well outside a species' usual climatic range, with little possibility of establishment. A living female of Palpares libelluloides in the Netherlands (Geijskes 1974) probably resulted from inadvertent importation of a living pupa from southern Europe. Flightlessness has developed in a number of lacewings. Independent wing reductions in Hemerobiidae are associated with fore wing hardening, occasional midline fusion, or hind-wing reduction. Examples are: Micromus acutipennis (Congo, humus-dwelling, wings short and narrow: Kimmins 1956), Nusalala andinus (a montane form from Colombia, hind wing reduced to a small lobe, fore wing short and rounded), the bizarre Hawaiian forms Pseudopsectra and Nesothauma (the former termed, by Zimmermann (1957) a 'spiny monster') and Conchopterella (Juan Fernandez Is.: Handschin 1955). The Holarctic Psectra diptera is dimorphic, with macropterous and brachypterous forms in both sexes (MacLeod 1960, New 1966). A flightless coniopterygid is known from Europe, and it is very doubtful whether Brucheiser can fly. The single known female of Trichoma (Berothidae, Australia) is brachypterous (U. Aspock 1986).

Natural Enemies

18 19 20 21 22 23 24 01 02 03 04 05 06 07

HOURS Fig. 63. Nocturnal flight activity of Mantispidae in Uganda: the entry pattern into a light trap over 47 trap nights. (New & Haddow 1971).

A considerable amount of information is available on predators and parasites of Planipennia, but much of this relates to incidence of natural enemies rather than to any quantitative estimation of their effects on populations. In addition to 'conventional' predators, cannibalism is perhaps not uncommon (p.45, Duelli 1981). Virtually nothing is known of diseases of Planipennia.

50

Predators A wide range of arthropod predators take Planipennia as part of a broad prey spectrum and, probably, few of these are specific feeders. Mass emergence or unusual abundance of particular lacewings may temporarily attract high intensity of predation. Thus, massed emergences of Australian Ithonidae are heavily attacked by ants (Myrmecia, Ectatoma: Tillyard 1922) so that less than half may survive for more than a few minutes. Insectivorous birds also exploit such aggregations (Riek 1974 a). Different stages may be attacked by different predators. Free-swimming first instar larvae of Sisyridae are attacked by a range of largeplankton feeders (such as Hydra), larger swimming larvae are eaten by fish and (after moving onto the bank to pupate) by a range of arthropods such as spiders, centipedes and ants, and adults have been noted as prey of salticid spiders, Diptera, mites and tree frogs (Parfin & Gurney 1956). Asilid flies and scorpions have been recorded eating adult antlions. Many families of Planipennia have no specific records of predators, but the broad spectrum recorded for Chrysopidae indicate the kinds likely to take other groups. Apparently relatively specific attackers of chrysopids include a Bembix wasp found with 10 adults in its nest (Mexico: Evans 1978), and the clerid beetle Hydnocera developing within cocoons (California: Clancy 1946). Adults are attacked by Odonata (which can capture lacewings in flight: Mehra & Dasgupta 1969), Asilidae, Empididae, spiders, various birds, and bats; eggs are eaten by mites (Principi 1956) and other chrysopids (Nineta flava eggs eaten by larvae of Chrysopa septempunctata: Canard 1983); cocoons may be opened by predatory caterpillars, Coleoptera and Raphidioptera larvae (summary: Alrouechdi et al. 1984). Forcipomyia midges are sometimes found attached to wing veins of adult chrysopids.

Planipennia (Lacewings)

sentative of groups having a larger collective host range: several Ceraphronidae and Encyrtidae attack early stages of Coniopterygidae (Castellan 1980, Viggiani 1967); chrysopid eggs are parasitised by Telenomus (Scelionidae) and Trichogramma (Trichogrammatidae) in many parts of the world, and virtually all superfamilies of parasitic Hymenoptera are represented in the diverse parasite/hyperparasite complex of Chrysopidae {New 1984d, Clancy 1946). The biology of many is discussed by Clancy (1946) and Principi (1948). Recorded levels of parasitisation vary considerably, and most are based on rearings from field collections of cocoons. Figitid attack on Hemerobiidae may exceed 5 0 % (Lipkow 1970) and chrysopid samples range from about 1 0 - 2 0 % parasitisation (on Citrus in Florida: Muma 1959) to more than 80 % (on olives in Europe: Alrouechdi et al. 1981).

Defences

Parasites

A wide range of defences against, especially, predators has been postulated. These range through laying eggs on stalks (p. 86) camouflage and protective resemblances such as mimicry, chemical and visual antagonism, and sophisticated avoidance behaviour. Many of these also have other interpretations. The debris-carrying habit of many chrysopid larvae, for example, is widely presumed to protect the larvae (Principi 1946), but may also serve to conceal the predator from its prey. C. slossonae larvae in North America are attacked by ants tending the waxy aphid prey, and steal aphid wax to cover their bodies: they thus 'blend', both chemically and visually, into the 'background' of wax. When larvae are denuded, they are much more likely to be attacked and removed by ants (Eisner et al. 1978). Even when wax-covered larvae were attacked, the wax provided defence by clogging ant mouthparts and eliciting cleaning behaviour. The substantial amount of time the larvae spent covering themselves with wax suggested a high investment in defence. Ants may occasionally act as kleptoparasites in antlion pits (Lucas 1986).

Some hymenopterous parasitoids are much more specific attackers of particular Planipennia. As examples, Figitine cynipoids (Xyalaspis, Anachar is, Aegilips) have been reared from hemerobiid cocoons in many parts of the world; Heloridae are specific to chrysopids, attacking larvae and emerging from the host cocoon; Chrysopophthorus (Braconidae) is a parasite of adult chrysopids in Europe; Brachycyrtus (Ichneumonidae) is apparently limited to chrysopid cocoons; the pteromalid Sisyridivora cavigena occurs on Sisyridae in North America (Brown 1951), and some unusual Chalcididae are specialised solitary endoparasites of myrmeleontid larvae ( S t e f f a n 1971). Other parasitoids are repre-

The resemblance of some adult mantispids to Hymenoptera is presumed to be mimetic. The five distinct colour morphs of Climaciella brunnea in Costa Rica are each apparently a Batesian mimic of a different polistine wasp (Polistes, Synoeca) (Opler 1981) and the resemblance probably aids protection of these conspicuous insects from vertebrate predators. A North American population of this species contains only two morphs (Redborg & MacLeod 1983). There ae two distinct forms of mimetic behaviour in C. brunnea (Fig. 64) (Boyden 1984): one leads to resemblance of the wasp in a standing posture and the other, in which wings are spread and the abdomen raised and expanded, was interpreted as a 'startle dis-

Economic Importance

51

Fig. 64. 'Mimicry display'of the mantispid Climaciella brunnea v. instabilis: a) normal preycapture position; b) mimicry display, first position (wings held vertically, abdomen inflated); c) mimicry display, second position (abdominal jerking, as if'stinging') (see text, from Boyden 1984).

Fig. 65. 'Startle display' of Ascalaphidae: male of Haploglenius luteus, dorsal, with thoracic patch exposed (A) and hidden (B) (Eisner & Adams 1975).

play'. Males of some New World Ascalaphidae also have an apparent startle display, in which a hinged flap covering the pronotum is suddenly reflexed to expose a contrasting cream or white patch (Fig. 65) (Eisner & Adams 1975). Mimetic resemblances between adult chrysopids with and without 'stink glands' have been postulated (Semeria 1984). Prothoracic glands of C. oculata produce a secretion, containing 9 0 % tridecene, which repels ants (Blum et al. 1973), and many other chrysopids exude a very strong odour from such glands. These species (such as C. perla) are sometimes strongly patterned, and may combine visual and chemical cues to deter predators by both Batesian and Mullerian mimicry. Semeria (1984) suggested the possibility that some other patterned taxa lacking stink glands may mimic these. The disagreeable odours of chrysopid adults have been long known (McLachlan 1874). Several of the mice tested by Blum et al. (1973) rejected chrysopids after olfactory examination, and moved away from them. Some ascalaphids, and others, also have a strong scent. Chemical defence may also be employed by larvae of some Chrysopidae, as their anal secretion has been noted to paralyse Iridomyrmex ants (Kennet 1948). Larvae of some surface-active myrmeleontid larvae (Brachynemurus nebulosus in Florida: Brack 1978) have a strong orange-red-black-white pattern resembling that of some local Mutillidae (Dasymutilla), and may be a generalised Batesian mimic of these. It is not clear whether the prime role of such adult features as those noted above is truly defence, or whether they are sexual-display or mate-

attractant. Some scents seem to be associated with pleuritocavae (p. 60) or similar structures limited to one sex. Death feigning by adult Hemerobiidae, in which they fold their wings and drop to remain motionless for some time, may also be defensive. Flying chrysopids have very specialised avoidance behaviour in response to calls of echolocating flying bats (Miller 1984, Miller & MacLeod 1966, Miller & Oleson 1979). Similar responses were obtained from using trained Pipistrellus bats and simulated bat cries. C. carnea respond by folding their wings and passively nosediving, a behaviour which normally removes the insect from the bat's acoustic field. Occasionally, the falling insect is detected by the bat (and is then vulnerable) and, just as the bat is about to make the catch, the chrysopid suddenly flips open its wings, which gives it a further chance of escape. Other avoidance behaviours include circling, zig-zagging, and irregular flight. The physiological mechanisms underlying this behaviour are now well understood (Miller 1984).

Economic Importance It has been claimed that Planipennia are amongst the insects most beneficial to mankind, an opinion arising from the role of Chrysopidae, Hemerobiidae and Coniopterygidae as predators of pest insects on a wide range of crops. Historically, members of some other families have also been considered as potential biocontrol agents: Psychopsidae (Tillyard 1919) and Ithonidae (Tillyard 1923), but neither appears to be manipulable, sufficiently abundant or to have the 'right' feeding

52

habits. It was, for example, believed that ithonid larvae could be important predators of subterranean scarab larvae before their unusual feeding habits (p. 43) were recognised. Conversely, adult Ithonidae have occasionally been considered aesthetic nuisances when they enter dwellings in large numbers. The practical benefit of some other families has scarcely been appraised in economic terms, although the insects may be abundant. The potential of Coniopterygidae as control agents against Phylloxera aphids on oak in Britain was recognised by Withycombe (1924), but most more recent attention has been paid to the role of larvae as predators of mites, especially Tetranychidae in orchards (stone fruits: Putman & Heme 1966, Castellari 1980; citrus: Fleschner & Ricker 1953). A.juniperi may be effective against Carulaspis scales on ornamental juniper (Stimmell 1979). The major potential for Coniopterygidae, though, may be against mites in controlled environments, such as glasshouses. Hemerobiidae have long been noted as useful for control of various aphids (Smith 1923, Laidlaw 1936, Balduf 1939) but details of these roles are often not clear {New 1988d). Several studied species have lower developmental temperature thresholds than chrysopids in similar environments, so that they are active in the field earlier than other predators. Hemerobius pacificus is the only common predator active in winter on artichokes in California (Neuenschwander & Hagen 1980) and hemerobiids are notable early predators also in Californian alfa-alfa fields (Neuenschwander et al. 1975). Micromus tasmaniae in Australia and New Zealand occurs commonly in association with aphids, and most Hemerobiidae which have attracted attention in economic contexts are relatively generalist species of Hemerobius or Micromus s. 1. Control of pests by Chrysopidae, especially by C. carnea, has received immense attention. Development of mass rearing techniques, pioneered by Finney (1948), Ridgway et al. (1970), Hagen & Tassan (1972), Tulisalo (1984) means that enormous numbers can now be reared under controlled conditions using semiartificial diets. Adults are maintained on a mixture involving commercial preparations of cultured Saccharomyces fragilis yeast, sugar and water. Artificial diets for larvae (Vanderzant 1969) are a valuable adjunct, but do not entirely replace the need for a proportion of natural prey, and mass rearing of insects such as grain moths (Sitotroga cerealella) for their eggs is necessary to provide natural food. Limited storage of all lacewing stages is possible. Biological control has involved field releases of eggs or larvae (Ridgway & Murphy 1984), with varying degrees of success against particular targets. Releases against aphids on vegetable crops have sometimes been very successful, and

Planipennia (Lacewings)

have received major attention in the USSR, as have releases on eggplant and potatoes against Leptinotarsa decemlineata. Substantial reduction in populations of bollworm and budworm on cotton in the USA were obtained by releases of 25,000 larvae/ha and very high control at 250,000 larvae/ha. Promising results against a wide range of insect pests and tetranychid mites have been obtained in several other parts of the world, both outside and in glasshouses. As well as mass releases, attempts to attract chrysopids onto crops by sprays of food supplements based on protein hydolysates (Hagen