The Antlered Crane Fly, Tanyptera dorsalis (Walker) (Diptera: Tipulidae), in Michigan and a Review of its Distribution and Biology Stephen W. Taber* Abstract - The highly variable and strongly sexually dimorphic crane fly Tanyptera dorsalis (Antlered Crane Fly) is reported as a new state record from Michigan. The geographic distribution of the species and its biology are summarized, and a photograph of an adult of each sex is provided. Perusal of a monographic publication reporting more than 200 tipulid species collected during four years of field work on The University of Michigan’s George Reserve in Livingston County, MI, indicated that the remarkable crane fly featured here is not on that list (Rogers 1942). The species was not reported from Michigan before that study or since, although it would be expected to occur in the state from what has been previously published about its distribution elsewhere. Here I confirm the presence of Tanyptera dorsalis (Walker) (Antlered Crane Fly) in Michigan, summarize what was previously known about its distribution and biology, and add original data from my own field work. The field site is located in Oxford Swamp, Newaygo County, MI, 6.5 km east of Brohman, just within the tree line between shrub-carr swamp and a forest of Betula papyrifera Marshall (Paper Birch), Acer rubrum L. (Red Maple), Tilia americana L. (American Basswood), and Prunus serotina Ehrhart (Wild Black Cherry). Its coordinates are 43.69°N, 85.72°W. Despite nearly weekly visits to this location over the course of five years, between snow melt and deer archery season at the beginning of October, the Antlered Crane Fly was never caught by aerial net while walking about in this habitat and in others nearby, though many other tipulid species were caught in this manner. The species was encountered only in the collection canisters of a large Malaise trap erected beneath a Red Maple tree, where 5 males and 4 females were retrieved, all from late May to early June 2006. The Antlered Crane Fly is remarkable within its family for the antler-like antennae of the males (Fig. 1), and the great variation in color within each sex and between the two sexes. These color differences provoked a proliferation of species and varietal names that have long since been synonymized. Synonyms attributable to color variation include Tanyptera succedens (Walker), Tanyptera fumipennis (Osten Sacken), Tanyptera frontalis (Osten Sacken), and Tanyptera topazina (Osten Sacken) (Alexander 1965). The wings vary from smoky black to hyaline to a condition described as “topazine” or tinged with crystalline pale yellow. The body varies from black to various combinations of black and red and yellow, and it seems likely that these colors, often shiny and iridescent, give the harmless flies a Batesian mimicry of wasps (though these appear to be wasps that use their ovipositor for laying eggs rather than for defense). One coloration difference between the two sexes at the Michigan site is reminiscent of the differences seen between many stick insect species (Phasmatodea), in which the male resembles a shiny wooden twig and the female mimics green Notes of the Northeastern Nat u ral ist, Issue 17/2, 2010 337 *Biology Department, Saginaw Valley State University, 7400 Bay Road, University Center, MI 48710; swtaber@svsu.edu. 338 Northeastern Naturalist Notes Vol. 17, No. 2 vegetation. In the present case, the male Antlered Crane Fly of the frontalis form also resembles a twig in shape and color and texture, including the node-like appearance of the junctions of the abdominal segments, and is thus cryptically adapted for life among trees, but the female of the fumipennis form is a Batesian mimic instead, with the red and black warning colors of the wasps that they resemble. Three of the Michigan males are rusty red with a black head and nearly hyaline wings (frontalis form), one is almost entirely black with blackish wings (fumipennis form), whereas one is black with a rusty red genital bulb and blackish wings, and does not key out to any previously described form (Alexander 1942). All four females key out to the fumipennis form, which—with its black and red coloration, blackish wings, and remarkably wasp-like abdomen (Fig. 2)—much resembles the pimpline ichneumonid wasps that were also collected in Oxford Swamp by the Malaise trap. The predominance of frontalis form males and fumipennis form females in these samples is notable in light of an observation made in New York on 31 May 1936, when these two color forms were collected while mating (Alexander 1942). The various color forms of the Antlered Crane Fly are not recognized as having taxonomic significance. Figure 1. Tanyptera dorsalis; frontalis form male from Oxford Swamp, Newaygo County, MI. Figure 2. Tanyptera dorsalis; fumipennis form female from Oxford Swamp, Newaygo County, MI. 2010 Northeastern Naturalist Notes 339 In an extensive survey of Wisconsin crane flies, comments for what are now recognized as the three color morphs of fumipennis, frontalis, and topazina indicate that all three were known from Wisconsin and the first morph was also known from Illinois, but neither of the latter two from the states surrounding Wisconsin (Dickinson 1932), which includes Michigan. Nevertheless, the work of Rogers in southeastern Michigan, which lasted for a little more than three years, concluded with impressive coverage and with 206 taxa reported (Rogers 1942). An unpublished list, assembled 45 years later, of crane flies known to occur in the entire state, only approximately doubled the number found by Rogers in a single area of a single county (Byers 1979). The list of states and provinces where the Antlered Crane Fly was previously known to occur included Maine, New Hampshire, Vermont, Massachusetts, Connecticut, New York, New Jersey, Maryland, Virginia, Tennessee, North Carolina, Ohio, Illinois, Wisconsin, Minnesota, Québec, Nova Scotia, and Ontario (Alexander 1940, 1942). No new state or province records have been published in the last 24 years (Harper and Lauzon 1985). A more recent publication than any cited above reported the Antlered Crane Fly from Minnesota, where it flew in late June and mid-July and was described as “rare” and of the topazina form, not of the frontalis color morph found in Michigan (Byers 1979). In Québec, the fly was found in a habitat much like that of the Michigan site, with secondary Paper Birch forest approximately 60 years old dominating previously lumbered and burned land (Harper and Lauzon 1985). The habitat preference for adults has been reported as open mesophytic or mixed woodlands (Alexander 1942), and the monthly records for all of these reports taken together include only May, June, and July. The Michigan material examined so far includes both males and females, but spans only the shorter time interval of late May to early June. A perusal of stored, frozen material from three field seasons (mid-April to late September each year) disclosed no additional specimens. The larval or maggot stage lives in the wood of decaying hardwood trees, such as Paper Birch, from which the color form reported here was bred when maggots were collected long ago in Maine, where adults fly from late May to late June (Alexander 1962). Paper Birch logs are abundant at the site where the Michigan material was collected by Malaise trap. In Wisconsin, larvae were found within decaying and sound wood such as that of maples (Dickinson 1932), which were presumably logs (Alexander 1942), and the Michigan site is rich in Red Maple in particular, beneath which the Malaise trap was erected in a spot surrounded by Paper Birch both standing and fallen. The Antlered Crane Fly occurs at elevations from at least as low as 283 m above sea level (Oxford Swamp, MI), to 1.6 km asl (Indian Gap of the Great Smoky Mountains National Park in Tennessee, where the frontalis color morph was in flight in early June [Alexander 1940]). A crane fly census published more than 60 years later from this same national park reported the species from most locations (Petersen et al. 2005). Two additional crane fly species that may be described with the common name of “Antlered,” and that are closely related to T. dorsalis, are Ctenophora apicata Osten Sacken and Ctenophora nubecula Osten Sacken. Neither insect is currently known from Michigan despite considerable tipulid collection in that state. They may be distinguished from T. dorsalis by the intermediate flagellomeres of the Ctenophora antenna, which are each four-branched rather than three-branched (Alexander and Byers 1981). Most reports for both species are from the eastern United States and Canada, and both are expected to occur in Michigan because C. apicata is reported from as far west as Minnesota (Byers 1979), and C. nubecula is known from 340 Northeastern Naturalist Notes Vol. 17, No. 2 Illinois (Alexander 1965). Furthermore, C. apicata larvae develop in elm (Ulmus), and Ctenophora species develop in willow (Salix), birch (Betula), cherry (Prunus), and beech (Fagus) in Europe (Alexander 1920). Ctenophora nubecula is believed to develop in oak (Quercus) (Rogers 1930). All of these plant genera occur at the Michigan habitat where the Antlered Crane Fly was found. The latter fly develops in Red Maple (Alexander 1920), which is especially abundant there. Finally, why did James Speed Rogers not encounter this most bizarre-looking of all crane flies now known to occur in Michigan? He did not use a Malaise trap, probably because its invention was published precisely in the midst of his studies, but neither did the collectors of earlier generations have such a means and it was they who described the species and its several color forms, too. Nevertheless, the only specimens encountered by the present writer in Michigan were found in this passively operating device that collects around the clock. Acknowledgments. I thank Laurie G. Reed of the Saginaw Valley State University Physics Department for photographing the specimens shown here and Dean Deborah R. Huntley of The College of Science, Engineering, and Technology at Saginaw Valley State University for subsidizing the cost of this publication. Literature Cited Alexander, C.P. 1920. The Crane-Flies of New York. Part II. Biology and Phylogeny. Cornell University Agricultural Experiment Station Memoir 38:691–1133. Alexander, C.P. 1940. Records and descriptions of North American crane-flies (Diptera). Part I. Tipuloidea of the Great Smoky Mountains National Park, Tennessee. American Midland Naturalist 24:602–644. Alexander, C.P. 1942. Family Tipulidae. Pp. 196–486, In G.C. Crampton, C.H. Curran, and C.P. Alexander (Contributors). Guide to the Insects of Connecticut. Part VI. The Diptera or True Flies of Connecticut. First Fasicle. Connecticut State Geological and Natural History Survey Bulletin 64. Alexander, C.P. 1962. The crane flies of Maine. Maine Agricultural Experiment Station Technical Series Bulletin T4, Orono, ME. Alexander, C.P. 1965. Family Tipulidae. Pp. 16–90, In A. Stone, C.W. Sabrosky, W.W. Wirth, R.H. Foote, and J.R. Coulson (Eds.). A Catalog of the Diptera of America North of Mexico. Agricultural Research Service, United States Department of Agriculture, Washington, DC. Alexander, C.P., and G.W. Byers. 1981. Tipulidae. Pp. 153–19, In J.F. McAlpine, B.V. Peterson, G.E. Shewell, H.J. Teskey, J.R. Vockeroth, and D.M. Wood (Coordinators). Manual of Nearctic Diptera. Volume 1. Research Branch, Agriculture Canada, Biosystematics Research Institute, Ottawa, ON, Canada. Monograph No. 27. Byers, G.W. 1979. Summer crane flies of Lake Itasca vicinity, Minnesota. University of Kansas Science Bulletin 51:603–613. Dickinson, W.E. 1932. The crane-flies of Wisconsin. Bulletin of the Public Museum of the City of Milwaukee 8:139–266. Harper, P.P., and M. Lauzon. 1985. The crane fly fauna of a Laurentian woodland, with special reference to the aquatic species (Diptera: Tipulidae). Revue d’Entomolgie du Québec 30:3–22. Petersen, M.J., C.R. Parker, and E. Bernard. 2005. The crane flies (Diptera: Tipuloidea) of Great Smoky Mountains National Park. Zootaxa 1013:1–18. Rogers, J.S. 1930. The summer crane-fly fauna of the Cumberland Plateau in Tennessee. Occasional Papers of the Museum of Zoology, University of Michigan, Ann Arbor, MI. Rogers, J.S. 1942. The Crane Flies (Tipulidae) of the George Reserve, Michigan. University of Michigan Museum of Zoology, Ann Arbor, MI. Miscellaneous Publications No. 53, 128 pp.+ 8 plates.