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Predaceous insects

Robber Flies Capturing Prey

8-3-16  robber fly 009The robber fly family, Asilidae, is one of the largest families of flies.  All robber flies are predaceous and are recognized by their long bodies, forward-facing beaks and a tuft of hairs above the beak.  You find them on the ground or on leaf tips and other sunny spots where they survey the area for flying insects.  Once a robber fly has spotted a suitably-sized prey, it darts out and impales it with its stout beak.  It then inserts its needlelike “tongue” into the prey’s neck, eye or other weak spot, immobilizing the insect and liquefying its innards with an injection of saliva that contains nerve poisons and enzymes that break down proteins. Finally, it drinks its meal.  Pictured is a species of robber fly in the genus Diogmites, whose members are known for dangling by a foreleg while dining.

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