Revision of the genus Tylencholaimus de Man, 1876. Remaining species.

Abstract

The present paper deals with the taxonomy of five species belonging to the genus Tylencholaimus de Man, 1876. Two of them are prodelphic: T. stecki Steiner, 1914 and T. vulvulatus Rahman, Jairajpuri, Ahmad & Ahmad, 1987; they are characterized by having perioral region not disc-like, anterior part of the pharynx expanding gradually to the basal bulb, and posterior genital branch more than two body widths long. The other three species are opisthodelphic: T. intermedius n. sp., T. gertii Kruger, 1965 and T. pakistanensis Timm, 1964. These five species are described and illustrated. Moreover, T. rossi Yeates, 1979 is transferred to Tantunema Siddiqi, 1979 as Tantunema rossi (Yeates, 1979) n. comb. Several species recently described or transferred to Tylencholaimus, and others considered species inquirendae are briefly discussed.