Wikipedia
Toxophora
Toxophora is a genus of flies belonging to the family Bombyliidae (bee-flies). There are 47 described species, distributed throughout the world, although they are most abundant in Southwestern United States and western Mediterranean. World catalog of bee flies (Diptera: Bombyliidae) They are strange, stout, robust flies with a hunchbacked form, with a body length of 6–12 mm and wings 4 to 7.5mm. Most species are black with banding or spots.
Larvae feed in the nest of wasps of the genus Odynerus.
Ectoparasitoids in nests of solitary bees & wasps Research.net. Yeates, D. The evolutionary pattern of host use in the Bombyliidae (Diptera): a diverse family of parasitoid flies