Evaniidae
（重定向自Ensign Wasp）
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The Evaniidae, also known as the ensign wasps or hatchet wasps, are a family of parasitic 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 feed on cockroaches, and develop inside the egg-cases (oothecae) of their hosts.