about 50

The enigmatic scarab beetles are a small family (Glaresidae Semenov-Tian-Shanskii & Medvedev , 1932) of poorly-known beetles related to the scarab beetles. Although members of the single genus Glaresis occur in arid and sandy areas worldwide (except Australia), only adults have ever been collected (typically at lights), and both the larvae and biology of glaresids are as yet unknown.

These beetles are small, ranging from 2.5 to 6.0 mm, and have the stocky appearance typical of scarabs, with short heavy spurred legs. Color ranges from tan to dark brown, and the back is covered with short setae.

Efforts to raise glaresids in the laboratory were undertaken in the 1980s by C. H. Scholtz and others, but were unsuccessful.

Originally Glaresis was classified with Trogidae, and has many characteristics of "primitive" scarabaeoids , but no affinities to any of the other primitive groups. Scholtz has argued that the Glaresidae are the most primitive type of scarabaeoid .

Reference

• Mary Liz Jameson , "Glaresidae", in Ross H. Arnett, Jr. and Michael C. Thomas, American Beetles (CRC Press, 2001), vol. 2