Revision of Palearctic species of the genus Dimorphaphorura (Collembola: Onychiuridae: Onychiurinae: Oligaphorurini) with description of new species

In this paper, the Palearctic genus DimorphaphoruraBagnall, 1949 (Collembola: Onychiuridae), is revised. The diagnosis of the genus is defined within the tribe Oligaphorurini based on the development of the furcal area, shape of furcal rudiment, and furcal chaetotaxy. Six new species are described: D. olenaesp. n. from Ukraine, D. inyasp. n . , D. pseudoinyasp. n., D. sibiricasp. n., D. caucasicasp. n. , and D. sophyaesp. n. from Russia. The type species of the genus, D. differensBagnall, 1949 is redescribed, and the lectotype and paralectotypes are designated. All previously known species are redescribed or with additional characters complemented: D. alnus ( Fjellberg, 1987 ) comb. n. , D. chatyrdagi ( Kaprus’, Weiner & Pomorski, 2002 ) comb. n. , D. daii ( Pomorski, Skarżyński & Kaprus’, 1998 ) comb. n. , Dimorphaphorura eremia ( Kaprus’,Weiner & Pomorski, 2002 ) comb. n. , D. hackeri ( Christian, 1986 ) comb. n. , D. irinae ( Thibaud & Taraschuk, 1997 ) comb. n. , D. melittae ( Christian, 1993 ) comb. n. , D. pseudoraxensis ( Nosek & Christian, 1983 ) comb. n. , D. raxensis ( Gisin, 1961 ) comb. n. , D. steposa ( Kaprus’, Weiner & Pomorski, 2002 ). An identification key to all Dimorphaphorura species is provided.