The North American Cerylonidae (Coleoptera: Clavicornia)

The Cerylonidae are a amily o small to minute beetles (usually 2 ram. or less) which occur most commonly in fo.rest litter and under bark. At present, there are about 4o genera and over 3oo described species known rom all o the major zoogeographic regions. Crowso.n (I955) qrst recognized the Cerylonidae as an independent clavicorn family, including the cerylonines and murmidiines, as well as Euxestus and its allies; but these groups have been treated a.s tribes of the heteromerous amily Colydiidae by both Hetschko (I93O) and Arnett (1968). In their world generic revision of the family, Sen Gupta and Crowson (1973) added .4nommatus Wesmael, ./tbromus Reitter, and Ostomopsis Scott, while transferring Eidoreus Sharp (--Eupsilobius Casey) to the Endomychidae. The present paper consists of a revision of the IO genera and 18 species of Cerylonidae occurring in America north of Mexico. With respect to the composition of the family and that of its major subordinate groups, we have followed the classification presented by Sen Gupta and Crowson; the interrelationships among the subgroups, however, are still obscure, so we have treated the Euxestinae, Anommatinae, Metaceryloninae (not North American), Murmidiinae, Ostomopsinae, and Ceryloninae as independent subfamilies. The following abbreviations have been used in keys and descriptions" PLmpronotal length, PW--pronotal width, EL--elytral length, EWmelytral width, and TL--sum of PL and EL. The word "length" refers to the total length, including the head, and is