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Family Conopidae - Thick-headed Flies

Stylogaster neglecta? - Stylogaster neglecta - female black/white possible wasp mimic fly? - Physocephala furcillata Clown fly - Zodion americanum Conopid being attacked by an ant - Physocephala Thick-headed Fly - Physocephala floridana - female Fly - Physocephala furcillata Zodion Zodiac sp. - Zodion
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)
Explanation of Names
Conopidae Latreille 1802
Greek conops (κωνωψ) 'gnat' (verbatim, 'cone-faced')(1)
67 spp. in 9 genera in our area(2), ~830 spp. in 52 genera total(3)
4-18 mm(2)
Medium-sized, blackish or brownish flies, many of which mimic thread-waisted wasps (Sphecidae)(4)(5):
in some genera (i.e. subfamily Conopinae) the abdomen long, with a slender, wasp-like pedicel; in others abdomen more uniform in width
head slightly broader than thorax; head often with prominent grooves on face (beneath the antennae)
antennae usually long, about the same length as head or longer; projecting forward, 3-segmented, third segment bearing either a dorsal arista or a terminal style
ocelli present or absent
proboscis long and slender, elbowed and projecting upward in some species
wing venation similar to that in the Syrphidae, but with spurious vein absent (except in Physoconops)
both male and female conopids have eyes widely separated at the top of the head (= "dichoptic"(6))
Conopids may be distinguished from syrphids their long, slender, stiff proboscis bent forward from the base; and by the lack a spurious vein (except in Physoconops) (4).
Examples of wing venation:
Physocephala       Zodion
Physoconops       Stylogaster
Key to CA spp. in(7)
Worldwide and throughout NA
Adults usually found on flowers
Adults take nectar. Larvae are endoparasites of wasps, bees, ants, crickets, cockroaches, and some Diptera (mostly calyptrate); host group varies by subfamily(8)
Life Cycle
At least in some groups, females oviposit on hosts in flight and have complex structures to lay eggs by prying open the host exoskeleton (below left). In Stylogaster (below right), the ovipositor is long and robust, the eggs having a barbed tip for penetration and attachment of the host in the manner of a harpoon.
See Also
Print References
Banks N. (1916) Synopses of Zodion and Myopa with Notes on other Conopidae. Ann. Ent. Soc. Am. 9: 191-200 (Full Text)
Bohart, G. E. (1938). Synopsis of the genus Dalmannia in North America (Diptera, Conopidae). Pan-Pac. Ent. 14(3): 132-136. (PDF of typed transcription...with equivalent text, but not the original typeset journal article!)
Bohart G.E. (1941) The oviposition of conopid flies upon smaller andrenid bees. The Pan-Pacific Entomologist 16: 91. (Full Text)
Bohart, G.E. and MacSwain, J.W. (1940). A conopid fly parasite of Megachile. The Pan-Pacific Entomologist 17: 95. (Full Text)
Burt, Trevor (2015). Taxonomic revision of four Nearctic Conopidae (Insecta: Diptera) genera (Dalmannia, Roberstonomyia, Stylogaster and Zodion) with notes on all other Nearctic genera. Master of Science Thesis, Carleton University. (Full Text)
Camras S. (1943) Notes on the North American species of the Zodion obliquefasciatum group (Diptera: Conopidae). Ent. News 54: 187-191 (Full text)
Camras, S. (1945). A study of the genus Occemyia in North America (Diptera: Conopidae). Ann. Ent. Soc. Am. 38: 216-222. (Full Text)
Camras S. (1953) A review of the genus Myopa in North America (Diptera: Conopidae). Wasmann J. Biol. 11: 97-114 (Full text)
Camras, Sidney (1955), "A Review of the New World Flies of the Genus Conops and Allies (Diptera: Conopidae)", Proc. U. S. Nat. Mus., Vol. 105, pp. 155-187 (Full Text)
Camras S. (1957) A review of the New World Physocephala (Diptera: Conopidae)". Ann. Ent. Soc. Am. 50:213-218.
Camras S. (1996) New information on the New World Physocephala (Diptera: Conopidae). Ent. News 107: 104-112 (Full text)
Camras, S. & P. Hurd (1957). The Conopidae flies of California, Bull. Cal. Insect Surv. 6(2) 19:49, (7)
Clements, D. K. (1997). The Enemy Within: Conopid flies as parasitoids of bees and wasps in Britain. British Wildlife, 8(5): 310-315.
Foote, B.A. and Gittins, A.R. 1961. The conopid flies of Idaho (Diptera: Conopidae). Bulletin of the Brooklyn Entomological Society 56: 1–5. (Full Text)
Freeman B.A. (1966) Notes on conopid flies, including insect host, plant and phoretic relationships (Diptera: Conopidae). J. Kans. Ent. Soc. 39: 123-131. (Full text)
Freeman B.A. (1968) Status of Zodion zebrinum, Z. auricaudatum, and Z. albonotatum (Diptera: Conopidae). Ann. ent. Soc. Am. 61: 276-278.
Gibson, J. F. and Skevington, J. H. (2013). Phylogeny and taxonomic revision of all genera of Conopidae (Diptera) based on morphological data. Zoological Journal of the Linnaean Society, 167: 43-81 (Full Text)
Gibson, J.F., Slatosky, A.D., Malfi, R.L., Rooulston, T., & Davis, S.E. (2014). Eclosion of Physocephala tibialis (Say) (Diptera): Conopidae) from a Bombus (Apidae: Hymenoptera) host: A video record J. ent. Soc. Ont. Volume 145: 49-58. (Full text)
Howell J.F. (1961) Biology of Zodion obliquefasciatum (Macq.) (Diptera: Conopidae). Bull. Wash. agric. Exp. Stn 51: 1-33.
Kröber, O. (1915). Die nord- und südamerikanischen Arten der Gattung Conops. Archiv fü Naturgeschichte, 81(5):121-160 (Full Text)
MacFarlane, R.P. and Pengelly, D.H. (1974). Conopidae and Sarcophagidae (Diptera) as parasites of adult Bombinae (Hymenoptera) in Ontario. Proceedings of the Entomological Society of Ontario 105: 55–59. (Full Text)
MacSwain, J.W. and Bohart, G.E. (1947). Some records of parasitism of solitary bees by conopid flies. The Pan-Pacific Entomologist 23: 30. (Full text)
Malfi, R.L., Davis, S.E., and Roulston, T.H. (2014). Parasitoid fly induces manipulative grave-digging behaviour differentially across its bumblebee hosts. Animal Behaviour 92: 213–220.
Otterstatter M.C. (2001). The Incidence of Parasitism by Conopid and Phorid Flies and its Effects on the Behaviour of Bumble Bees (Hymenoptera: Apidae). Master of Science Dissertation, Univ. of Calgary. 148 pp. (Full Text)
Otterstatter M.C., Whidden T.L., Owen R.E. (2002). Contrasting frequencies of parasitism and host mortality among phorid and conopid parasitoids of bumble-bees. Ecol. Entomol. 27(2): 229-237. (Full Text)
Parsons C.T. (1948). A classification of North American Conopidae. Ann. Ent. Soc. Am. 41: 223-246 (Full text)
Schmid-Hempel, P., Müller, C., Schmid-Hempel, R., and Shykoff, J.A. (1990). Frequency and ecological correlates of parasitism by conopid flies (Conopidae, Diptera) in populations of bumblebees. Insectes Sociaux 37: 14–30.
Severin H.C. (1931). Zodion fulvifrons Say, a parasite of the honey bee. Ent. News 48: 243-244. (Full text)
Skevington J.H., Thompson F.C., Gibson J.F. (2012). Sid Camras and his conopid legacy. Fly Times 49: 39-65 (Full text)
Stuke, J.-H., Skevington, J. H. (2007). The Conopidae of Costa Rica (Diptera). (Part 1: Conopinae-Conopini & Tropidomyiini). Zootaxa 1528:1-40 (Full Text)
Van Duzee M.C. (1927). A contribution to our knowledge of the North America Conopidae (Diptera). Proc. Calif. Acad. Sci. 17(18): 573-604 (Full text)
Van Duzee, M. C. (1934). Conopidae from North Dakota and the Rocky Mountain region. Annals of the Entomological Society of America 27: 315–323. (Full text)
Williston, S. W. (1882). The North American species of Conops. Trans. Conn. Acad. Arts & Sci., 4:325-342 (Full Text)
Williston, S. W. (1883). North American Conopidae: Stylogaster, Dalmannia and Oncomyia. Trans. Conn. Acad. Arts & Sci., 6:91-98 (Full Text)
Williston, S. W. (1885). North American Conopidae: Conclusion. Trans. Conn. Acad. Arts & Sci., 6:377-394 (Full Text)
Williston, S. W. (1892). Family Conopidae. Biologia Centrali-Americana: Insecta. Diptera. Vol. 3, pp. 79-86 (Full Text)