Robber fly (family Asilidae) with its prey,an Eastern tailed-blue butterfly (Everes comyntas). More than 4200 species of robber flies are known. The robber fly,or bee killer,is a predator of flying insects. It has large,protuberant eyes,which permits a broad field of view. Its neck and the front of its dorsal thorax are mobile,enabling the head to be turned in a wide arc when searching for prey. The robber fly has a short,powerful proboscis,used for sucking juices of its prey. Photographed in Pennsylvania,USA |