Evaniidae

Evaniidae is a family of parasitoid wasps also known as ensign wasps, nightshade wasps, hatchet wasps, or cockroach egg parasitoid wasps. They number around 20 extant genera containing over 400 described species, and are found all over the world except in the polar regions. The larvae of these solitary wasps are parasitoids that feed on cockroaches and develop inside the egg-cases, or oothecae, of their hosts.

==Description== Evaniidae have the metasoma attached very high above the hind coxae on the propodeum, and the metasoma itself is quite small, with a long, one-segmented, tube-like petiole, and compressed laterally over most of its length (segments 2–8). The ovipositor is short and thin. When active, these wasps jerk the metasoma up and down constantly, as referenced in their common names. The mesosoma is high, short, and heavily sclerotized, with a ridged and pitted surface. The head is largely immovable and attaches to the mesosoma on a short neck; with usually 13-segmented antennae that do not differ between males and females.