First records of troglobitic beetles from arkansas: Two new species of speleochus park (Coleoptera: Staphylinidae: Pselaphinae: Bythinini), and synonymy of subterrochus park with speleochus

The two species of pselaphine staphylinid beetles described herein represent the first unambiguous records of true troglobitic beetles from caves in the Ozark Plateau region of Arkansas. Speleochus macosar Carlton, new species, is based on a series of six specimens collected from Whippoorwill Cave, Madison County, northwestern Arkansas. Speleochus blanchardensis Carlton, new species, is based on a series of four specimens collected in Blanchard Springs Caverns, Stone County, north-central Arkansas. All specimens were collected from the zone of total darkness, deep within the caves. Comparison with other troglobitic species from the southeastern United States included within the genera Speleochus Park, 1951 and Subterrochus Park, 1960 suggest that all are congeneric. An updated description of Speleochus is provided and the following nomenclatural changes are proposed: Speleochus (= Subterrochus, new synonymy);Speleochus eurous (Park, 1960), new combination; Speleochus ferns Park, 1951, combination reinstated, and Speleochus steevesi (Park, 1960), new combination. The species described from Arkansas are the only members of the genus known from west of the Mississippi River Embayment. All others are described from caves in northern Alabama