Great Basin Naturalist


The taxonomic history of the genus Gymnodamaeus is reviewed for North American species. A new species, Gymnodamaeus chalazionus, is described from Colorado and compared with species from both the western and eastern U.S. Among other features, the new species differs from G. veriornatus Higgins, 1961, in the shorter interlamellar hairs and the surface structure of the notogaster and genital plates. The new species is also compared with G. quadricaudatus Jacot, 1937, G. pearsei and minor Banks, 1947; with G. gildersleeveae and ornatus Hammer 1952, from Canada, and with G. elegantulus Hammer, 1958, from South America. Twelve scanning electron micrographs are used to delineate some of the details of integument and other features.