Cuckoo Wasps

The cuckoo or ruby-tailed wasps constitute one of the most attractive families of Hymenoptera because of their brilliantly metallic coloration. Almost all of our species are either purple, blue or green, but many Palaearctic species are marked also with golden or ruby in specific patterns. ~The behavior and life history also make this a very fascinating group. All species are parasitic, and, as one common name implies, many of them exhibit behavior in the host nests similar to that of cuckoos in the nests of their bird hosts. Members of the small subfamilies Cleptinae and Amiseginae parasitize, respectively, the resting larvae of sawflies in their cocoons and eggs of walking sticks. Almost all species belonging to the Elampinae, Chrysididinae and Parnopinae have as their hosts solitary wasps or bees which nest in the ground or in cavities in wood or which build mud cells; one exotic species of Chrysis L. is known to parasitize the resting larva of the oriental moth in its cocoon. The parasite egg is deposited in the host cell while it is being provisioned by the mother wasp or bee. In most species the newly hatched chrysidid larva devours the host egg or young larva and then feeds on the provisions stored for the host. However, in species of Chrysura Dahlb. the parasite larva attaches to the host larva, sucks only a small amount of body fluids, and does not devour the host larva until the latter attains full growth and spins its cocoon. Eggs of Parnopes Latr. and Chrysis pellucidula Aar. are deposited in the host nest while the host wasp is provisioning; these parasite larvae also devour the resting host larva in its cocoon. The female of Chrysis fuscipennis Br. chews a hole in the host mud cell, oviposits therein, and the parasite larva develops on the resting larva of the host. ~The arrangement of genera in the Chrysididinae and division into Species Groups in Chrysis Linnaeus are by R. M. Bohart who also contributed new synonymy and distribution in both the Chrysididinae and Elampinae.