Larval Taxonomy of the Troginae 



in North America With Notes on Biologies 



and Life Histories 



(Goleoptera: Scarabaeidae) ' 



By Charles W. Baker ^ 

 Introduction 



The subfamily Troginae of the Scarabaeidae is represented by three 

 genera in North America: Trox^ Omorgus^ and Glaresis, of which 

 Omorgus is restored to generic status in this study. Only those species 

 of Trox and Omorgus which occur in North America are treated in 

 this bulletin. No attempt has been made to separate the species out- 

 side of North America into Trox s. st. and Omorgus. The subfamily 

 contains one other genus, Cryptogenius, which is restricted to South 

 America. 



The genus Glaresis is known from eight species in North America. 

 During this study numerous adults were collected in Oregon, but all 

 attempts to rear the larvae were unsuccessful. The biology of this 

 genus is unknown, and the placement of Glaresis within the Troginae 

 has been questioned by Crowson (1955). 



The adults and larvae of Trox and Omorgus can be characterized as 

 facultative animal necrophages. Records indicate that they feed on the 

 remains of a great many terrestrial animals as well as certain aquatic 



1 Modified from a thesis submitted in partial fulfillment of the requirements 

 for the Ph. D. degree. Department of Entomology, Oregon State University, Cor- 

 vallis, Greg. 



2 Department of Biological Sciences, Boise State College, Boise, Idaho. 



Technical Paper No. 2279, Oregon Agricultural Experiment Station 



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