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Home » Guide » Arthropods (Arthropoda) » Hexapods (Hexapoda) » Insects (Insecta) » Flies (Diptera) » "Aschiza" » Hover Flies (Syrphidae) » Eristalinae » Eristalini » Eristalina » Drone Flies (Eristalis)

Genus Eristalis - Drone Flies

Eristalis? - Eristalis arbustorum - female

Eristalis transversa, Transverse Flower Fly - Eristalis transversa - male

Fly with gold markings for ID - Eristalis transversa - male

Eristalinae? Hover Fly - Eristalis stipator

Classification

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)

Pronunciation

ih-RISS-tah-liss

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)

Numbers

2 subgenera, with 20 spp. in our area(2) and ~100 total(3)

Size

7-17 mm

Identification

Some species (e.g., E. tenax) resemble honey bees. Others are darker, less hairy, e.g. E. dimidiatus, E. nemorum.

Wing

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

Range

Holarctic, Neotropical, Afrotropical, Oriental(3); E. tenax is introduced from Europe

Season

Mar-Nov in NC(4), Apr-Oct in MN

Food

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

Remarks

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.

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. CJAI 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.

Contributed by Cotinis on 19 September, 2004 - 2:40pm
Additional contributions by Beatriz Moisset, Robin McLeod, Ted Kropiewnicki, Aaron Schusteff, v belov, KenW, PaleoJon
Last updated 25 May, 2024 - 1:24pm

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