Other Common Names
Drone Flies (sometimes applied to E. tenax only), Rat-tailed Maggots (larvae of E. tenax)
Synonyms and other taxonomic changes
Explanation of Names
, a kind of gemstone, maybe opal
(likely what Latreille meant)
2 subgenera, with 20 spp. in our area(2)
and ~100 total(3)
Some species (e.g., E. tenax) resemble honey bees. Others are darker, less hairy, e.g., E. dimidiatus, E. nemorum.
Moderately to very hairy; head broader than high and about as broad or slightly broader than thorax; antennae short, inserted near middle of head, third segment longest ventrally, while dorso-apically it is shorter and rounded; arista generally long; eyes range from bare to pilose, holoptic
to narrowly dichoptic
in male; mesonotum short and compact, rather convex; scutellum without fringe; stigmatic cross-vein present, spurious vein generally distinct, marginal cell closed, third vein deeply bent into apical cell and ending well above apex of wing, anterior cross-vein at or near middle of discal cell; hind femora slender to moderately thickened and without spurs, spines, or teeth; tibiae nearly straight or moderately arcuate; abdomen generally with yellow and black markings.
Key to species, courtesy of Martin Hauser:
For full-size version, click here
Text key to species by Bill Dean under the image below:
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
Fields, etc. with flowers
Adults take nectar. Larvae feed on small organisms in stagnant water.
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.
Hull F.M. (1925) A review of the genus Eristalis
in North America. Part I
| Part II
Ohio J. Sci. 25: 11–43, 285-312