Dioctria Atricapilla, Meigen 1804. Violet Black-Legged Robberfly. Length 10 mm to 12 mm
Flight Season… May to July
Widespread in the southern half of Britain
The violet black-legged robber fly usually waits on lower stems of grasses and attacks prey as it flies by.
The larvae usually grow up in dung piles or decaying organic matter, but they can also live in some soils.
Courting behaviour involves the male leading the courtship dance in front of the female. If he fails to impress, she will rapidly move her wings or fly away; otherwise the male will begin copulating.
This is the only Doctria species with all black legs. The wings are darkened towards the base, particularly in the male. The female has a golden face whereas in the male it is dark brown.
Habitat…. Grasslands where it usually rests on grass stems,
Predatory on small insects, particularly other flies and parasitic hymenopterans.
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