Pleocomidae

The rain beetles are a group of beetles found in the far west of North America. They spend most of their lives underground, emerging in response to rain or snow, thus the common name. Formerly classified in the Geotrupidae, they are currently assigned to their own family Pleocomidae, considered the sister group to all the remaining families of Scarabaeoidea. The family contains a single extant genus, Pleocoma, and one extinct genus, Cretocoma, described in 2002 from Late Cretaceous deposits in Mongolia.