Kite-tailed robberfly

Tolmerus atricapillus · Order: Diptera · Family: Asilidae

No source yet on danger. We have no source yet on whether it bites, stings or damages anything.
Kite-tailed robberfly
Photo: Cilla Moerman, CC BY

The kite-tailed robberfly is a small grey-black asilid about 11 to 14 mm long. It belongs to the Palearctic species Machimus atricapillus and looks much like other Machimus flies, making it hard to tell apart. Identification keys and illustrations are available in several works, including those by Wolff et al. (2021) and older sources like Seguy (1920).

Source: Wikipedia

How to recognize it

It is a small, grey-black asilid that is difficult to distinguish from other Machimus species.

Source: Wikipedia

Size

Adults measure about 11 to 14 mm in length.

Source: Wikipedia

Where it comes from

Machimus atricapillus is a Palearctic species.

Source: Wikipedia

Lookalikes

It is hard to tell apart from other Machimus flies. Keys, descriptions and illustrations are provided in works by Wolff, Gebel & Geller-Grimm (2021) and earlier authors.

Source: Wikipedia

More photos

Kite-tailed robberfly photo 3
Photo: Sascha Nunheim, CC BY
Kite-tailed robberfly photo 4
Photo: Barry Walter, CC BY
Kite-tailed robberfly photo 5
Photo: unknown, CC0
Kite-tailed robberfly photo 6
Photo: bristolian, CC BY

Same family (Asilidae)

Northeastern HammertailNortheastern HammertailEfferia aestuansHarmlessStripe-legged Robber FlyStripe-legged Robber FlyDioctria hyalipennisPlain-tailed Hanging ThiefPlain-tailed Hanging ThiefDiogmites neoternatusGolden-tailed BeebanditGolden-tailed BeebanditMallophora fautrixSand HammertailSand HammertailEfferia albibarbisBlack-tailed LaphriaBlack-tailed LaphriaLaphria flavicollis

Sources

  • Wikipedia: https://en.wikipedia.org/wiki/Machimus_atricapillus

Look it up elsewhere: GBIF · iNaturalist · BugGuide · Wikipedia

Text written 2026-10-22 from the sources above and checked sentence by sentence against them. Data fetched 2026-10-22.

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