Recently, Espanol (1968, 1970) redefined the subfamily Hedobiinae and, using the anatomy of adults, presented a key to separate the eight genera which form it. He also introduced some notable modifications, among them the inclusion of Ptilineurus and Clada in the subfamily and the elevation of Ptinomorphus Mulsant and Rey to generic rank. The latter genus includes, among others, the species P. imperialis Linnaeus and regalis Duftschmid, from Europe and P. granosus LeConte and angularus Fall from the United States of America.
de Viedma, Manuel G.
"Definition of the Subfamily Hedobiinae Based on Larval Characteristics (Coleoptera: Anobiidae),"
The Great Lakes Entomologist, vol 6
Available at: https://scholar.valpo.edu/tgle/vol6/iss2/3