Aquatic nematodes from Ethiopia: 4: the family Leptolaimidae Orley, 1880 sensu Lorenzen, 1981 (Chromadorida: Nematoda) with the description of Anonchus coomansi n sp

Four species of the family Leptolaimidae Orley, 1880 sensu Lorenzen, 1981 one of which is new to science are described from Lake Tana and River Abbay, North-western Ethiopia. Anonchus coomansi n. sp. is identified by its smoothly truncate lip region, short (7-10 mu m long) and typically barrel-shaped stoma, didelphic females, and males with 22-28 ventro-median, tubular and 80-112 pouch-like, alveolar supplements. Detailed descriptions of Aphanolaimus tudoranceai Zullini, 1988, Paraphanolaimus behningi Micoletzky, 1923 and Paraplectonema pedunculatum (Hofmanner, 1913) Strand, 1934 are given. An attempt has been made to define the identity of P. behningi clearly. Ejaculatory glands are reported in the genus Anonchus here for the first time. Scanning electromicrographs of A. coomansi n. sp. including that of its spicules, A. tudoranceai and P. behningi and a key to the species of Anonchus Cobb, 1913 are also presented