| abstract | The oribatid mite genus Ametroproctus, soil and litter inhabitants in the desert, alpine, and montane regions of western North America, is discussed. Two subgenera are recognized, Ametroproctus s.str. and Coropoculia. Their respective type-species, A. oresbios Higgins and Woolley and C. reticulata Aoki and Fujikawa, are redescribed, and newly discovered immatures of both species are described. Four new spcies are proposed, A. (Ametroproctus) tuberculosus, A. (A.) aridus, A. (Coropoculia) beringianus, and A. (C.) canningsi. A new gneric diagnosis is given, as well as a key to subgenera and species known from North America. |