Two new nematode species of the family Desmodoridae Filipjev, 1922, found in coral reefs in Vietnam, are described and illustrated. Metachromadora (Bradylaimus) tenuis sp. n. in body size and absence of precloacal supplements in males is close to M. (B.) asupplementa [Crites, 1961] and M. (B.) suecica (Allgen, 1929). It differs from both species by the comparatively thinner body, comparatively shorter tail, presence of bipartite basal bulb of pharynx and shorter spicules and gubernaculum [Crites, 1961]. The table of chief of morphological characters of males 12 valid species of the genus Metachromadora (Bradylaimus) is given. Spirinia laevioides Gerlach, 1963 was described from one female and two males from atoll in the Maldives. The description was short and incomplete. Since we had a lot of material available, it was decided to rewrite and reillustrate this species.
Vietnam, coral reefs, free-living nematodes, new species
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