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Robber Fly

Robber flies are also known as assassin flies. These insects can fly exceedingly fast and have a knack for catching large prey in the air. There are around 5,000 species across the world, and 900 here in the United States. Depending on species, adult flies can be as small as a quarter of an inch to as large as 2 inches long. Commonly, robber flies have hunched thoraxes and tapering abdomens, with the narrow side connecting to the thorax. Their eyes are located on the sides of their head. Flies can be found perching on stones or branches, waiting for their next victim to fly past. They feed on insects such as bees, wasps, and even dragonflies. They catch their prey in the air, pierce them with a needle-like mouthpart that injects a venom that paralyzes the prey, and suck out the insides of the insect. Females lay their eggs and larvae hatch and live in the soil, stumps, or rotting logs. Larvae are yellowish white in color and consume other insectlarvae.

robber fly or assassin fly