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Home » Guide » Arthropods (Arthropoda) » Hexapods (Hexapoda) » Insects (Insecta) » Flies (Diptera) » Orthorrhapha » Asiloidea » Stiletto Flies (Therevidae)

Family Therevidae - Stiletto Flies

Representative Images

Black Fly Tiger-striped diptera - Thereva fucata - female Therevid Fly sp.? Pelecorhynchidae or Rhagionidae - Thereva Therevidae Thervinae - female insect

Classification

Kingdom Animalia (Animals)
Phylum Arthropoda (Arthropods)
Subphylum Hexapoda (Hexapods)
Class Insecta (Insects)
Order Diptera (Flies)
No Taxon (Orthorrhapha)
Superfamily Asiloidea
Family Therevidae (Stiletto Flies)

Explanation of Names

Therevidae Newman 1834
see Thereva
Common name refers to narrow, tapering abdomen

Numbers

~150 spp. in 30 genera in our area(1), >1,600 spp. in >120 genera of 4 subfamilies worldwide(2)(3)

Size

2.5‒15 mm(1)

Identification

Key to Nearctic genera(4)
Larva

Range

cosmopolitan, most diverse in Australia(5)

Habitat

usually open areas: adults on foliage, flowers, dry ground along sandy areas; larvae in sand or decaying wood(1)

Food

Adults are nectar feeders; larvae prey on soil arthropods(2)

Remarks

The long, serpentine larvae hunt rapidly slithering through soil and may be mistaken for potworms or earthworms(6)

See Also

similar to robber flies (Asilidae) but without the beard, have more slender legs and no depression between the eyes(1)

Works Cited

1.American Insects: A Handbook of the Insects of America North of Mexico
Ross H. Arnett. 2000. CRC Press.
2.Stiletto Flies of the World
3.An annotated catalogue of the New World Therevidae (Zootaxa 3600 (1): 001 – 105 )
DONALD W. WEBB, STEPHEN D. GAIMARI, MARTIN HAUSER, KEVIN C. HOLSTON, MARK A. METZ, MICHAEL E. IRWIN, GAIL E. KAMPMEIER & KRISTIN. 2013. Magnolia Press.
4.Therevidae home page
5.Australian Faunal Directory
6.Hidden Company that Trees Keep: Life from Treetops to Root Tips
James B. Nardi. 2023. Princeton University Press.
Contributed by john and jane balaban on 12 September, 2004 - 5:01pm
Additional contributions by Mike Boone, cotinis, Robin McLeod, Hartmut Wisch, Bbarnd, Vox Sciurorum, v belov, Marci Hess
Last updated 7 April, 2024 - 1:21pm

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