SOME SPECIES OF HELICOTYLENCHUS STEINER, 1945 FROM SOUTH-AFRICA (NEMATODA, HOPLOLAIMIDAE)

A total of 49 populations of the genus Helicotylenchus Steiner, 1945 f rom various localities in South Africa were studied. H. delanus sp. n. , collected from the rhizosphere of Pinus patula is described. The spe cies is characterized by the posterior position of the vulva (V = 73-7 6%), reduced posterior genital branch (25-44 mu m), and position of ph asmids (five annuli posterior to anus) in females and by body length ( 497-629 mu m), position of excretory pore (85-94 mu m from anterior en d), styler length (22-26 mu m), spicule length (18-23 mu m), and guber naculum length (6-8 mu m) in males. H. krugeri Van den Berg & Heyns, 1 915 is synonymized with H. martini Sher, 1966. H. paracanalis Sauer & Winoto, 1975 and H. variabilis Philips, 1971 are new recordings for So uth Africa. The male of H. indicus Siddiqi, 1963 is described for the first time and H. brevis (Whitehead, 1958) Fortuner, 1984, H. exallus Sher, 1966, and H. vulgaris Yuen, 1964 are redescribed. (C) Orstom/Els evier, Paris.