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Genus Eristalis - Drone Flies

Fly - Eristalis arbustorum Is this Eristalis dimidiata? - Eristalis dimidiata Genus Eristalis bee fly mimic ? - Eristalis arbustorum Fly - Eristalis dimidiata Eristalis sp.?? - Eristalis obscura - female Eristalis tenax Incidental Eristalis - Eristalis tenax Drone Fly - Eristalis tenax
Kingdom Animalia (Animals)
Phylum Arthropoda (Arthropods)
Subphylum Hexapoda (Hexapods)
Class Insecta (Insects)
Order Diptera (Flies)
No Taxon ("Aschiza")
Family Syrphidae (Hover Flies)
Subfamily Eristalinae
Tribe Eristalini
Subtribe Eristalina
Genus Eristalis (Drone Flies)
Other Common Names
Drone Flies (sometimes applied to E. tenax only), Rat-tailed Maggots (larvae of E. tenax)
Synonyms and other taxonomic changes
reviewed in(1)
Explanation of Names
Eristalis Latreille 1804
Latin eristalis, a kind of gemstone, maybe opal (likely what Latreille meant)
2 subgenera, with 20 spp. in our area(2) and ~100 total(3)
7-17 mm
Some species (e.g., E. tenax) resemble honey bees. Others are darker, less hairy, e.g. E. dimidiatus, E. nemorum.
Keys to species by Bill Dean at
Larva's anterior spiracles dark brown; prolegs with crochets in three rows with spicules gradually becoming smaller below
Holarctic, Neotropical, Afrotropical, Oriental(3); E. tenax is introduced from Europe
Mar-Nov in NC(4), Apr-Oct in MN
Adults take nectar. Larvae feed on small organisms in stagnant water.
Life Cycle
Larvae, at least of E. tenax, live in eutrophic water, have tail that serves as "snorkel" for breathing. They are called rat-tailed maggots.
Larva, puparium, female ovipositing
Eggs of E. tenax are occasionally swallowed by humans and the larvae live in the human intestinal tract, where they cause "myiasis". E. tenax sometimes emerges from carrion, closely resembles honey bee. This may account for the biblical story of honeybees nesting in a dead lion.
Internet References
Works Cited
1.Eristalis (Diptera: Syrphidae) from America North of Mexico
Telford H.S. 1970. Ann. Ent. Soc. Am. 63(5): 1201-1210.
2.Key to the genera of nearctic Syrphidae
Miranda G.F.G, Young A.D., Locke M.M., Marshall S.A., Skevington J.H., Thompson F.C. 2013. Can. J. Arthropod Identification 23: 1-351.
3.Austalis, a new genus of flower flies (Diptera: Syrphidae) with revisionary notes on related genera
Thompson F.C. 2003. Zootaxa 246: 1-19.
4.Insects of North Carolina
C.S. Brimley. 1938. North Carolina Department of Agriculture.
5.Syrphidae of Ontario