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Species Physocephala burgessi

unknown fly - Physocephala burgessi Thick-headed Fly - Physocephala burgessi Conopid of some kind ? - Physocephala burgessi - female Wasp-like - Physocephala burgessi - male Conopid on a high ridge - Physocephala burgessi Physocephala sp. - Physocephala burgessi Hornet, Wasp or Mimic fly??? - Physocephala burgessi fly - Physocephala burgessi
Kingdom Animalia (Animals)
Phylum Arthropoda (Arthropods)
Subphylum Hexapoda (Hexapods)
Class Insecta (Insects)
Order Diptera (Flies)
No Taxon ("Acalyptratae")
Superfamily Sciomyzoidea
Family Conopidae (Thick-headed Flies)
Subfamily Conopinae
Genus Physocephala
Species burgessi (Physocephala burgessi)
Synonyms and other taxonomic changes
Synonymy below from (1), hyperlinks go to original descriptions:
Conops burgessi Williston, 1882
Physocephala brevirostris Van Duzee, 1927
10-11 mm
Our only (almost) entirely red species. Flies in western half of U.S. and Canada.
Head: Entire face and frons yellowish, including facial grooves. Cheeks reddish. Top of head (vertex) reddish-yellow. There is a light reddish-brown (rarely blackish) medial stripe from top of head to antenna bases, where it forks and continues a short ways down sides of facial ridges. No stripe around eyes. Proboscis short, brownish-red, tip black.
Antenna: Red, the 1st segment very short (barely 1/3 x 2nd segment).
Thorax: Red with a wide median brown stripe from base to center of thorax. Obscure black areas around wing bases and end of thorax.
Legs: Mostly red. Front coxae blackened in front. Shins (tibiae) base half yellowish, rest red. Feet darker red. Claws dark.
Wings: Upper half of wings dark. Small hyaline area in R5, along 4th long. vein. Lower wings hyaline, except for streak in discal cell along 5th vein. Halters yellow, base of stem brown.
Abdomen: Red, can have darker shading on sides of segment 2 (petiole) and 3. May have very narrow yellow transverse stripe on segments 1 and 2. Top of last 2 segments may have a very light yellow dusting. Female pad (theca) on underside of segment 5 very small, dark red.
California to Texas, north to western Canada (Alberta to B.C.) (1)
Flight time: June to August
Food: Parasites of wasps and bees, especially the American Bumblebee Bombus pensylvanicus. Also parasitizes Bumblebee Bombus sonorus in California.
Williston's original 1882 description, as Conops burgessi, can be read online here.
Holotype female #02402 from California deposited at the California Academy of Sciences as Physocephala brevirostris Van Duzee
Type by Williston adult #MCZT_440 In Museum of Comparative Zoology, Osten Sacken Collection, Harvard - location unknown as P. burgessi.
Cotypes male and female, 16 from Colorado; Mendocino, California (Snow Entomological Collections, Lawrence, Kansas); location of others unknown.
Camras collection of 28 Physocephala burgessi donated to the Field Museum of Natural History, Chicago, Ill.
See Also
Some reddish specimens of P. texana may resemble burgessi, but the latter can be recognized by darker red color, black anterior coxae (usually yellowish to reddish in texana), and a single dark mark in the center of the thorax (dorsum of texana's thorax is usually predominantly black).
Note that Bohart(1941) discusses in detail ways to distinguish P. texana (there referred to using the synonym P. affinis) and P. burgessi.
Print References
Bohart, George E. (1941). A review of the genus Physocephala of the western United States (Diptera, Conopidae). Pan-Pacific Entomologist, 17(3):141-144 (Full Text)
Camras, Sidney, and Paul D. Hurd, Jr. (1957). The Conopid Flies of California (Diptera). Bulletin of the California Insect Survey. Vol.6, No.2. (Available as PDF)
Transactions of the Connecticut Academy of Arts and Sciences, 1877-1882. Vol. 4, pp. 337 to 338 – as Conops burgessi by Williston
Transactions of the Connecticut Academy of Arts and Sciences, 1882-1885. Vol. 6, pg. 391- keys by Williston.
Proceedings of the California Academy of Sciences, 1927-1928. Vol. 16, pp. 579 to 580 – as Physocephala brevirostris by Van Duzee
Annals of the Entomological Society of America, 1957. Vol. #50, #3, pg. 213; keys pg. 218 by Camras.
Entomological News, 1996. Vol. 107, #2, pp. 110-111 – keys by Camras.
The Diptera Families of British Columbia, 2006. Pg. 84 by Scudder and Cannings
Fly Times, 2007. Pg. 43 – Camras collection.
Works Cited
1.A Catalog of the Diptera of America North of Mexico
Alan Stone, et al. 1965. United States Department of Agriculture.