Hairy Robber Fly

All robber flies have stout, spiny legs and 3 simple eyes (ocelli) in a characteristic depression between their two large compound eyes. They also have a usually dense moustache of stiff bristles on the face; this is called the mystax, a term derived from the Greek mystakos meaning "moustache" or "upper lip". The mystax probably affords some protection for the head and face when the flies deal with struggling prey; various Asilidae prey on formidable species including stinging Hymenoptera, powerful grasshoppers, dragonflies and even other Asilidae, in fact practically anything of a suitable size. Some Asilidae do however specialise in smaller prey, and this is reflected in their more gracile build. In general the family attacks a very wide range of prey, including other flies, beetles, butterflies and moths, various bees, ants, dragon and damselflies, ichneumon wasps, grasshoppers, and some spiders. They do so apparently irrespective of any repugnatorial chemicals the prey may have at its disposal. Many Asilidae when attacked in turn do not hesitate to defend themselves with their proboscides and may deliver intensely painful bites if handled incautiously.
The antennae are short, 3-segmented, and sometimes bear a bristle-like structure called an arista.
Many Asilidae have long, tapering abdomens, sometimes with a sword-like ovipositor. Others, for instance Laphria are fat-bodied bumblebee mimics.
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