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Home » Guide » Arthropods (Arthropoda) » Hexapods (Hexapoda) » Insects (Insecta) » Flies (Diptera) » "Aschiza" » Hover Flies (Syrphidae) » Syrphinae » Syrphini » Toxomerus

Genus Toxomerus

Classification · Synonyms and other taxonomic changes · Explanation of Names · Numbers · Size · Identification · Range · Food · Life Cycle · Remarks · See Also · Works Cited

Syrphid Fly spp? - Toxomerus marginatus - male

Syrphid from Oregon with Distinctive Stripe Pattern - Toxomerus occidentalis

Toxomerus marginatus? - Toxomerus marginatus

Very dark Syritta pipiens? - Toxomerus occidentalis - male

Classification

Kingdom Animalia (Animals)

Phylum Arthropoda (Arthropods)

Subphylum Hexapoda (Hexapods)

Class Insecta (Insects)

Order Diptera (Flies)

No Taxon ("Aschiza")

Family Syrphidae (Hover Flies)

Subfamily Syrphinae

Tribe Syrphini

Genus Toxomerus

Synonyms and other taxonomic changes

Mesogramma Loew 1866, Mesograpta Loew 1872

Moved to Syrphini per recent paper

Explanation of Names

Toxomerus Macquart 1855

From Greek 'bow thigh' (refers to the bow-shaped metafemur)

Numbers

14 spp. in our area(1)(2)(3), hundreds total

Size

5‒13 mm

Identification

Key to our species in (4)

Pattern on abdomen characteristic(5); eye with a notch on back margin

Colors vary depending on temperature during pupation: under hotter conditions, the yellow/orange increases and the background gets lighter, but if it was cold, the dark increases and the orange parts become darker. Larvae and puparia bright green.

Range

New World & tropical Africa; in our area:

T. marginatus: much of the US & so.Canada; common

T. geminatus: e.NA; common

T. politus: so. Canada to Argentina; uncommon

T. occidentalis: w.NA; common

10 spp. restricted to FL

Food

Larvae of most species feed on aphids

Life Cycle

Eggs laid singly on plants near aphids. Pupation in soil cavities in spring; adults emerge in summer.(5)

Egg laying

Remarks

"extremely diverse in the tropics with many, many undescribed species and over 100 described species." ‒Jeff Skevington

See Also

Allograpta

Works Cited

1.	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.

2.	Toxomerus mutuus

3.	A Catalog of the Diptera of America North of Mexico Alan Stone, et al. 1965. United States Department of Agriculture.

4.	Field/Photo ID for Flies: Fly Guide

5.	National Audubon Society Field Guide to Insects and Spiders Lorus and Margery Milne. 1980. Knopf.

Contributed by Cotinis on 10 April, 2004 - 1:03am
Additional contributions by john and jane balaban, Beatriz Moisset, Robin McLeod, Chuck Entz, v belov, Arturo Santos, zdanko
Last updated 25 May, 2024 - 6:55pm

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