Robber Fly

Description:

Insects in the Diptera family Asilidae are commonly called robber flies. The family Asilidae contains about 7,100 described species worldwide. All robber flies have stout, spiny legs, a dense moustache of bristles on the face (mystax), and 3 simple eyes (ocelli) in a characteristic depression between their two large compound eyes. The mystax helps protect the head and face when the fly encounters prey bent on defense. The antennae are short, 3-segmented, sometimes with a bristle-like structure called an arista. The short, strong proboscis is used to stab and inject victims with saliva containing neurotoxic and proteolytic enzymes which paralyze and digest the insides; the fly then sucks the liquefied meal through the proboscis. Many species have long, tapering abdomens, sometimes with a sword-like ovipositor. Others are fat-bodied bumblebee mimics. Adult robber flies attack other flies, beetles, butterflies and moths, various bees, ants, dragon and damselflies, Ichneumon wasps, grasshoppers, and some spiders.

Habitat:

Habitat and Food Source(s): Adults have piercing-sucking mouthparts. Adult robber flies perch on stems of low plants or other objects and attack prey in the air. They feed on bees, beetles, dragonflies, other flies, grasshoppers, leafhoppers, wasps, and other insects. Larvae live in the soil, in wood and other habitats, feeding on organic matter, other arthropods such as white grubs, beetle pupae and grasshopper egg masses, and they may be carnivorous.