Scientific Report on the Belgian Expedition to the Great Barrier Reef in 1967. Nematodes IX Four new species of Quadricoma Filipjev (Nematoda, Desmoscolecida)

The following species are described: Q. papillata sp.n., characterized by its head‐shape with broad truncated anterior end and in males by the possession of 2 single short, stout ventral genital papillae situated anterior to the middle of the body; Q. lizardiensis sp.n., closely related to Q. papillata but distinguished from the latter by its head‐shape with a pronounced distally widened anterior border and the absence of genital papillae in the male; Q. freudenhammeri sp.n., characterized by its head‐shape with an anteriorly tapering naked front part with thickened, sclerotized cuticle and a rounded posterior part covered with thin cuticle and by the stoma with cheilorhabdia; Q. noffsingerae sp.n., characterized by its head‐shape with widened truncated anterior border surrounding 6 sometimes protruding lips, each with a tube‐like papilla and by the position of the ocelli situated along the posterior half of the long cylindrical oesophagus.