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Family Tabanidae - Horse and Deer Flies

Deer Fly - Chrysops ater - female fly (Tabanidae) - Tabanus trimaculatus - female Chrysopsinae - Deer Flies Chrysops callidus - Chrysops callidus Chrysops flavidus agg. - Chrysops Hybomitra - female Leucotabanus annulatus? - Leucotabanus annulatus - female Deer fly (with squished abdomen) - Chrysops excitans Chrysops cf. geminatus - Chrysops montanus - female
Kingdom Animalia (Animals)
Phylum Arthropoda (Arthropods)
Subphylum Hexapoda (Hexapods)
Class Insecta (Insects)
Order Diptera (Flies)
No Taxon (Orthorrhapha)
Infraorder Tabanomorpha
Family Tabanidae (Horse and Deer Flies)
Other Common Names
Bulldog Flies, Clegs, Yellow Flies of the Dismal Swamp, Greenheads, Gad Flies, Copper Heads
Explanation of Names
Tabanidae Latreille 1802
350 spp. in 31 genera in our area(1)(2), 145 spp. in Canada and Alaska; almost 4,500 in ~160 genera worldwide(3)
8-28 mm
Regional keys: n. NA(3), e. Canada(4)(5), CA(6), ID(7), ME(8), MI(9), OH(10), TX(11), VA(12), PNW (13)
Medium to large flies, females take blood; some are pests. The notched posterior margin of abdomnal tergite 1 is unique. Typical characteristics:
stoutly built flies with large squamae (scales above the halteres, also called calypters);
feet with 3 pads (as opposed to 2);
antennomere 3 elongated, made up of several fused parts, sometimes with a prominent tooth at base
veins R4 and R5 fork to form a large 'Y' across the wing tip.
Worldwide and throughout NA; analysis of distribution in NA in (3)
larvae mostly in wet soil in marshes/bogs and at water margins; a few spp. in sand/gravel in fast-flowing streams; others also in drier soils(14)
Year round in FL, summer further north
adult females feed on vertebrate blood, usually of warm-blooded animals; males (also females in a few spp. in all 3 subfamilies) visit flowers
larvae mainly carnivorous, a few eat detritus
Life Cycle
larval stage up to 2 or more years, esp. in the north(14)
The bite is effected by stabbing with the mouthparts and slicing the skin with scissor-like movements of the finely serrate, knife-like mandibles and smaller maxillae. After capillaries are ruptured, anti-coagulant saliva is pumped out through the hypopharynx, and the blood is lapped up using the labella –mouthparts images (Thomas 2012).
Eyes may have striking color pattern; Knüttel & Lunau (1995, 1997) suggest these colours filter light to improve contrast detected by the eye pigments themselves, and play a role in sexual signalling
Print References
Internet References
Taxon profile (Squitier 2011)(17)
Works Cited
1.American Insects: A Handbook of the Insects of America North of Mexico
Ross H. Arnett. 2000. CRC Press.
2.Catalog of Tabanidae (Diptera) of North America north of Mexico
Burger J.F. 1995. International Contributions on Entomology 1(1): 100pp.
3.The horse flies and deer flies of Canada and Alaska (Diptera: Tabanidae)
Teskey H.J. 1990. The insects and arachnids of Canada, Pt. 16. Ottawa: Agriculture Canada. 381 pp.
4.Tabanidae of Canada, east of the Rocky Mountains 1: a photographic key to the species of Chrysopsinae and Pangoniinae
Thomas A.W., Marshall S.A. 2009. Canadian Journal of Arthropod Identification No. 8.
5.Tabanidae of Canada, east of the Rocky Mountains 2: a photographic key to the genera and species of Tabaninae...
Thomas A.W. 2011. Canadian Journal of Arthropod Identification No.13.
6.Adult and immature Tabanidae (Diptera) of California
Middlekauff, W. W. and R. S. Lane. 1980. University of California Press.
7.The horse flies and deer flies of Idaho
Nowierski, R. M. and A. R. Gittins. 1976. Research Bulletin, Agricultural Experiment Station, University of Idaho College of-Agriculture. 96, 1-48.
8.The horse flies and deer flies of Maine (Diptera, Tabanidae)
Pechuman L.L., Dearborn R. 1996. Maine Agric. & Forest Exp. Sta. Technical bulletin 160, iv+24 pp.
9.A synopsis of the Tabanidae (Diptera) of Michigan
Hays, K.L. 1956. 1956. University of Michigan, Museum of Zoology.
10.Tabanidae of Ohio with a catalogue and bibliography of the species from America north of Mexico
James Stewart Hine. 1903. Columbus: Press of Spahr and Glenn.
11.The horse and deer flies (Diptera: Tabanidae) of Texas
Goodwin and Drees. 1996. 1996. Southwestern Entomological Society.
12.Horse Flies and Deer Flies of Virginia (Diptera: Tabanidae)
Pechuman L.L. 1973. The Insects of Virginia 6: 92 pp.
13.The Horse Flies and Deer Flies of Idaho, Oregon and Washington State
14.Manual of Nearctic Diptera Volume 1
Varies for each chapter; edited by J.F. McAlpine, B.V. Petersen, G.E. Shewell, H.J. Teskey, J.R. Vockeroth, D.M. Wood. 1981. Research Branch Agriculture Canada.
15.An annotated checklist of the horse flies, deer flies, and yellow flies (Diptera: Tabanidae) of Florida
Zettel Nalen C.M., Kline D.L., Sutton B.D., Müller G., Cilek J.E. 2015. Fla. Entomol. 98: 479-488.
16.The Tabanidae (Diptera) of Louisiana
Tidwell M.A. 1973. Tulane Studies Zool. Bot. 18: 1-95.
17.University of Florida: Featured Creatures