Precipitation-triggered-emergence
Guides
Pleocomidae
Rain Beetles
Pleocomidae, known as rain beetles, is a family of scarabaeoid beetles found in western North America. The family contains a single extant genus, Pleocoma, with two extinct genera known from the fossil record. Adults emerge in response to rain or snow events, giving the group its common name. The family is considered the sister group to all remaining families of Scarabaeoidea. At least one species, Pleocoma dubitabilis dubitabilis, has been documented as a pest of Christmas trees.