Coe, 1926
Body elongate, oval, flattened, broadly rounded at front and tapering gradually posteriorly; length 10-24 mm; rhynchocoel nearly as long as body; stylet armature comprising a slightly curved basis with about 8 conical stylets; 30 proboscis nerves; 18-24 pairs of intestinal diverticula; females with 10-18 pairs of ovaries; males with compact cluster of 4-6 spermaries on each side of body in front of brain.
Distribution: Taken between depths of about 600-1750 m, although nets drawn to the surface from 4800 m have contained specimens. Known from the North Pacific (south of the Aleutian Trench, in the submarine canyon at the entrance to Monterey Bay, California, and in the Coronado Trough off southern California), South Pacific (south of the East Pacific Ridge), North Atlantic (between 45º-50ºN and 29º-30ºW) and the South Atlantic (Angola Basin).