Studies on the rare nematode genus Mylodiscus Thorne, 1939 with first report of its male

Mylodiscus nanus Thorne, 1939 is re-described based on specimens collected from various localities in India, Singapore, Japan and Costa Rica. Variations were observed in the shape of the lip region, amphids, guiding ring, cardia, vagina and tail. A single male of this species reported for the first time is characterized by having four well spaced ventromedian supplements, a long slender dorylaimoid spicule measuring 66 μm and a short conoid tail.