Catalogue of Geadephaga (Coleoptera, Adephaga) of America, north of Mexico Author Bousquet, Yves Agriculture and Agri-Food Canada, Central Experimental Farm, Ottawa, Ontario, Canada bousquety1@yahoo.com text ZooKeys 2012 2012-11-28 245 1 1722 http://dx.doi.org/10.3897/zookeys.245.3416 journal article http://dx.doi.org/10.3897/zookeys.245.3416 1313-2970-245-1 FFFF52503A0AFF882450FFB66D45FF8E 578462 Genus Opisthius Kirby, 1837 Opisthius Kirby, 1837: 60. Type species: Opisthius richardsoni Kirby, 1837 by monotypy. Etymology. Uncertain, possibly from the Greek opisthen (behind) or opisthios (hinder) [masculine]. Bousquet and Smetana (1996: 218) suggested that the name possibly reflect Kirby's assignment of Opisthius to follow Elaphrus in his paper. Diversity. One North American species. Identification. The species was treated in Lindroth's (1961a: 88-90) monograph on the Carabidae of Canada and Alaska.