Sphex

(Zool.) Any one of numerous species of sand wasps of the genus Sphex and allied genera. These wasps have the abdomen attached to the thorax by a slender pedicel. See Illust. of Sand wasp, under Sand.

Sphex fly
(Zool.) any one of numerous species of small dipterous flies of the genus Conops and allied genera. The form of the body is similar to that of a sphex.

Sphex

a genus of wasps of the family Sphecidae. The body length is 12–30 mm. The adults feed on flowers while the larvae feed on long-horned grasshoppers, crickets, small locusts, and other insects that have been paralyzed by the sting of an adult female sphex. The female digs a hole in the ground and then begins her search for prey, which she paralyzes by inserting her stinger into the thoracic nerve ganglia. She places the prey in the hole and lays an egg on it. After filling the hole with food, the female seals it and begins digging a new one. The paralyzed insects remain alive for as long as 40 days.

There are about 250 widely distributed species of spheges; about 50 species occur in the USSR. The wasps have very little practical significance. The species S. aegyptiacus usually follows injurious migratory locusts and preys upon them.