Genus Nagelus

SEM face view broadly oval, and laterally elongated, with labial disc partially or completely fused with first lip annulus, lip annulus sectors also partially or completely fused together. Amphid apertures within the structure made by the first annulus and labial disc. The rest of labial annuli without longitudinal grooves or indentations. Deirids present in the lateral field at a level where the field has six lines. Tail irregularly conoid, with a distal hyaline part. Male spicules without well developed velum, cylindroid, blunt ended. Gubernaculum not protruding from cloaca.