Insecta: Diptera, Tanyderidae

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Freshwater Invertebrates of the Malaysian Region

Insecta: Diptera, Tanyderidae Darlene D. Judd Department of Zoology, Oregon State University, Corvallis, OR 97370 USA (Email: [email protected])

INTRODUCTION Tanyderids are rare, with fewer than 2000 specimens occurring in museum collections around the world (Judd 1999). Thirty-eight species are described in ten genera with the greatest species diversity found in the Southern Hemisphere (Alexander 1965; Alexander and Alexander 1967, 1973; Hutson 1980; Oosterbroek 1989; Wagner 1992; Hynes 1993). The family is morphologically distinct from other groups of basal flies in adult and larval life stages (Krzeminski and Judd 1997). Adults are small to large in size, 6–30 mm, with elongate, frail legs and patterned wings (Fig. 1A–C). The costal vein is complete with the following wing vein complement intersecting the outer margin: subcosta, five radial veins, four medial veins, one cubital vein, and one anal vein (Fig. 1B,C). The discal cell is always present and elongate with supernumerary crossveins present or absent. Cervical sclerites are well-developed, giving the overall appearance of an archaic bird (Fig. 2A). Thoracic meron and katepimeron are fused. Few pupae are described, making generalization risky. However, from those thus far known, all appear to be exarate. Larvae are aquatic and possess three pairs of elongate processes or filaments on the abdomen: one pair on the 8th segment, one pair on the ninth segment, and a pair extending from the apex of the anal proleg (Fig. 3E–H). A pair of anal prolegs with terminal claws is present on the ninth abdominal segment. The head capsule is complete, not retractile, but the posterior portion is partially enclosed by the prothorax. Spiracles are located on the lateral surface of the prothorax and dorsolateral surface of the 8th abdominal segment. GENERAL BIOLOGY Very little information is known on the biology and life history of tanyderids. Larvae are aquatic, and with few exceptions, appear to be free-living. Species of Protanyderus Handlirsch (Judd 1999; Exner and Craig 1976; Knight 1964), Radinoderus Handlirsch (Judd 1999), Mischoderus Handlirsch (Judd 1999), Araucoderus Alexander (Judd 1999), Protoplasa Osten Sacken (Alexander 1930) and Peringueyomyina Alexander (Wood 1952) occur in sand or cobble bottom substrates of lotic systems ranging from 2 nd order streams to large rivers. Species of at least one genus,

Insecta: Diptera, Tanyderidae

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Figure 1. A – Protanyderus yankovskyi; B – Protanyderus esakii; C – Radinoderus caledoniana. Abbreviations: Cu, cubitus; M, Media; R, Radius; Sc, Subcosta.

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Eutanyderus Alexander, mine into saturated woody debris of the streambed (Hinton 1966; Colless and McAlpine 1991). Free-living late instar larvae occasionally are collected in relatively high numbers. In smaller order streams, larvae are collected in glide areas of the reach, and appear densest above partially or fully submerged fallen trees or along the depositional side of cobble or sandbars. The highest densities of larval tanyderids encountered in large rivers are also on the depositional side of cobble bars. The duration of the larval life stage is unknown. Successful rearing of 4th instar larvae has been reported for Protoplasa fitchii Osten Sacken (Alexander 1930) and Eutanyderus wilsoni Alexander (Colless pers. com.). However, repeated attempts to rear species of Mischoderus, Araucoderus, Radinoderus (Judd pers. obs.), and Protanyderus (Judd pers. obs.; Craig and Extner 1976) have failed, with late instars dying prior to moulting, in some cases after more than three years in captivity. Pupae are described for one species of Protanyderus (Knight 1964) and two monotypic genera, Peringueyomyina (Wood 1952) and Protoplasa (Alexander 1930). However, with the exception of Wood (1952) the associated biological information is anecdotal. Adults are most frequently collected singly, but Alexander (1930) observed large mating swarms of Protoplasa fitchii. During daylight, adults can be found resting on the underside of riparian vegetation (Wood 1952; Woodley and Judd, pers. obs.) or under rocks and logs in the riparian zone (Judd and Brower pers. obs.). Flight activity appears correlated with sunset and the evening hours. Observations and collection records indicate that black or incandescent lights are useful for attracting some species of Protanyderus and Mischoderus. The family is not of medical or economic importance. However, according to Downs and Colless (1967) and Downs (1971), the adult mandibles of some species of Radinoderus are of the biting form found in other insectivorous feeding flies. REGIONAL TAXA Primitive crane flies are known from all biogeographic regions, but are of particular interest to scientists due to their bipolar pattern of distribution (sensu Du Reitz 1940). Although not reported from Malaysia, three species of Protanyderus are known from the northern Oriental region (Alexander and Alexander 1973) and 12 species of Radinoderus are reported from Australasia (Oosterbroek 1989). The following keys distinguish these two genera. Key to genera: adults 1. Radial vein 1 with apical third strongly arched (Fig. 1C); abdomen darkly colored with light tan oblong areas on lateral margins of tergal segments 2–7 ........................................ Radinoderus -

R1 straight (Fig. 1A,B), if curved restricted to apex; abdomen concolorous ranging from gray to tan to brown ....................................................................................................... Protanyderus


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Figure 2. A – Araucoderus gloriosus; B–C, Protanyderus esakii; D–E, Radinoderus sp.; B, D larval cranium, dorsal surface left of midline, ventral surface right of midline; C, E, hypostoma. Abbreviations: ant, antenna; crd, cardo; clyp, clypeus; frclyp apot, frontoclypeal apotome; g, galea; gn, gena; hyps hypostoma; lbr, labrum; mx plp, maxillary palp; os outer seta.

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Key to genera: larvae 1. Anterior margin of frontoclypeal apotome straight (Fig. 2D); genae complete on ventral surface (Fig. 2D); 9th abdominal segment with dorsal sclerotized plate, often extending and present on base of filament (Fig. 3H); base of anal proleg with tuft of setae on posterior margin (Fig. 3G) ....................................................................................................................... Radinoderus -

Anterior margin of frontoclypeal apotome emarginate (Fig. 2B); genae reduced, in part, present as a pair of lateral sclerites on ventral surface (Fig 2B); 9th abdominal segment without sclerotized plate; base of anal proleg without setal tuft ....................................................... Protanyderus

Genus Protanyderus Protanyderus is broadly distributed in the Palaearctic, western Nearctic and northern Oriental regions. Adults are usually small, 6–11 mm, but one species, Protanyderus yankovskyi Alexander, is larger with body extending 11.5–13 mm. The number of antennal segments appears fixed at 16, although some species are only known from a few specimens in poor condition. Wings range from 6–16 mm in length, with brown crossbands and/or random spots or freckles (Fig. 1A,B). A cross vein is usually present at the apical margin of cell bm (m3–m4) with medial veins 3 and 4 arising separately at point of origin (Fig. 1A,B; exceptions in Nearctic and Palaearctic). The male gonostylus is bifid, except in P. yankovskyi where the structure is not divided. Larvae are distinct from southern genera. The anterior margin of the frontoclypeal apotome has a median cleft and lateral extension (Fig. 2B). The labrum is present as pair of sclerites each bearing a single seta (Fig. 2B). A glandular duct was absent from three species examined (sensu Anthon 1988). The ventral portion of the cranium is significantly reduced posteriorly with genae, in part, represented by a pair of lateral sclerites (Fig. 2B). The hypostoma is present with the anterior margin with or without teeth (Fig. 2C). The mandible bears a large, flat, apically enlarged seta on the outer surface (Fig. 3A). the maxilla bears distinct galae and lacinia (Fig. 3C). The apical margin of the galea has tooth-like structures. The anal prolegs are elongate, often more than one third the length of proleg filament (Fig. 3E). The ninth abdominal segment bears no dorsal sclerotized plate. Genus Radinoderus Species of Radinoderus occur throughout New Guinea, the Molucccas, Solomons, New Caledonia, and eastern and southwestern Australia. Adults are small to large, 8–30 mm in body length. The number of antennal segments is variable, ranging from 20 to 24 segments depending on species. The wing length extends from 9.5 mm to 23 mm with variable banding pattern. Medial veins 3 and 4 have a common origin, either intersecting at the apical angle of cell bm or with a fused stem (Fig. 1C). The male gonostylus always single.


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Figure 3. A–C, Protanyderus esakii; D–H, Radinoderus sp.: A, D, larval right mandible; B, E, maxilla; C, F, 8th and 9th abdominal segments; G, anal proleg and base of filament; H, 9th abdominal segment dorsal surface left of midline, ventral surface right of midline. Abbreviations: an prlg, anal proleg; cla, claw; fil, filaments; gl, galea; os, outer setae; set tu, setal tuft.

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The anterior margin of the frontoclypeal apotome is straight. Labral and clypeal sclerites are present as separate, transverse bands, the former with setae present (Fig. 2D). The glandular duct (sensu Anthon 1988) is absent from three species examined. The ventral portion of the cranium is reduced posteriorly with genae forming a ventral bridge posterior to the hypostoma (Fig. 2D). The anterior margin of the hypostoma is serrate (Fig. 2E). The galea and lacinia of maxilla are not distinct (Fig. 3D). Anal prolegs are short, with a tuft of setae extending from the base of the proleg filament (Fig. 3F,G). The basal portion of 8th and 9th abdominal filaments are with (Fig. 3F) or without fine setae. The ninth abdominal segment bears a dorsal plate often extending to filament (Fig. 3H). REFERENCES Alexander C.P. (1930) Observations on the dipterous family Tanyderidae. Proceedings of Linnaean Society of New South Wales 55: 221–230. Alexander C.P. (1938) New or little-known Tipulidae from eastern Asia (Diptera). Philippine Journal of Science 67: 129–166. Alexander C.P. (1965) Superfamily Psychodoidea Family Tanyderidae. In Stone A., Sabrosky C.W., Wirth W.W., Foote R.H. and Coulson J.R. (Eds) A catalog of the Diptera of America north of Mexico. U.S. Government Printing Office, Washington, D.C. Alexander C.P. (1981) Tanyderidae. In: McAlpine J. F., Peterson B.V., Shewell G.E., Teskey H.J., Vockeroth J.R and Wood D.M (Eds.) Vol. 1, Manual of Nearctic Diptera,. Research Branch Agriculture Canada, Monograph No. 27. Canadian Government Publishing Centre, Hull, Quebec. Alexander C.P. and Alexander M.M. (1967) Family Tanyderidae. In: A catalogue of the Diptera of the Americas south of the United States. Departamento de Zoologia, Secretaria da Agricultura, São Paulo. Alexander C.P. and Alexander M.M. (1973) Superfamily Psychodoidea, Family Tanyderidae. In Delfinado M.D. and Hardy D.E. (Eds) Vol. 1, A catalog of the Diptera of the Oriental Region, Suborder Nematocera, University Press of Hawaii, Honolulu. Colless D.H. (1962) Notes on Australasian Tanyderidae, with description of a new species of Radinoderus Handl. (Diptera). Proceedings of the Linnaean Society of New South .87:309–311. Colless D.H. and McAlpine D.K. (1991) Diptera (Flies). In: Vol. II, The Insects of Australia. Cornell University Press, Ithaca, New York. Downs J.A. (1971) The ecology of blood-sucking Diptera: an evolutionary perspective. In Fallis A.M. (Ed.) Ecology and Physiology of Parasites: a Symposium. Toronto University Press, Toronto, Canada. Downs J.A. and Colless D.H. (1967) Mouthparts of the biting and blood-sucking type in Tanyderidae and Chironomidae. Nature 214: 1355–1356. Exner K. and Craig D. A. (1976) Larvae of Alberta Tanyderidae (Diptera: Nematocera). Quaestiones Entomologicae 12: 219–237. Hinton H.E. (1966) The spiracular gill of the fly Eutanyderus (Tanyderidae). Australian Journal of Zoology 14:365–369. Hutson A.M. (1980) Family Tanyderidae. In Crosskey R.W. (Eds) Catalog of the Diptera of the Afrotropical Region. British Museum (Natural History), London. Hynes C.D. (1993) The crane-flies of New Caledonia (Diptera Tanyderidae, Tipulidae). In Matile L. Najt J. and Tillier S. (Eds) Vol. 3, Zoologia Neocaledonica. Mémoires du Muséum National D’Histoire Naturelle 157.


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Judd D.D. (1999) Tanyderid specimen database. http://www.ent.orst.edu/juddd/tanyderi.htm Kariya S. (1935) On the Family Tanyderidae from Japan (Diptera). Mushi 8:39–41. [in Japanese with English description] Knight A. W. (1964) Description of the tanyderid pupa of Protanyderus margarita Alexander from Colorado. Entomological News 75:237–241. Krzeminski W. and Judd D. D. (1997) Family Tanyderidae. In Papp L. and Darvas B. (Eds) Vol. 2, Nematocera and Lower Brachycera, Contributions to a Manual of Palaearctic Diptera, Science Herald, Budapest. McAlpine J.F., Peterson B.V., Shewell G.E., Teskey H.J., Vockeroth J.R., and Wood D.M. (1981) Introduction. In Vol. 1, Manual of Nearctic Diptera. Research Branch Agriculture Canada, Monograph No. 27. Canadian Government Publishing Centre, Hull, Quebec. Oosterbroek P. (1989) Family Tanyderidae. In Evenhuis N.L.(Ed.) A catalog of the Diptera of the Australasian and Oceanian Regions. Bishop Museum Press and E.J. Brill, Honolulu. Peus F. (1958) Tanyderidae. In Lindner E. (Ed.) Die Fliegen der Palaearktischen Region. Lief. 200, Schweizerbart, Stuttgart. Wagner R. (1992) Family Tanyderidae. In Soós A., Papp L. and Oosterbroek P. (Eds).Catalogue of Palaearctic Diptera. Hungarian Natural History Museum, Budapest. Williams I.W. (1933) The external morphology of the primitive tanyderid dipteron Protoplasa fitchii O.S., with notes on the other Tanyderidae. Journal of the New York Entomological Society 41:1–35. Wood D.M. and Borkent A. (1989) Phylogeny and classification of the Nematocera. Pp. 1333–1370 In McAlpine J. F., Peterson B.V., Shewell G.E., Teskey H.J., Vockeroth J.R and Wood D.M. (Eds) Manual of Nearctic Diptera. Vol. 3. Research Branch, Agriculture Canada, Ottawa, Monograph No. 32, Canadian Government Publishing Centre, Hull, Quebec. Wood H.G. (1952) The crane-flies of the South-West (Diptera, Tipuloidea). Annals of the South African Museum 39:1–327.