Erannis is a geometer moth genus of the subfamily Ennominae. It is placed by some entomologists in the tribe Erannini as the type genus, but others merge this group into the tribe Boarmiini or Bistonini. The adults of these smallish moths typically live in the crowns of their host trees. The genus is most diverse in the Holarctic; few of the 12 or so known species occur in adjacent regions.