Moseley, 1875a
Body broad and oval, narrowing posteriorly to a pointed tail with no obvious caudal fin; lengths of 11-45 mm, widths of 3.5-23 mm and a thickness of 3 mm have been recorded; rhynchocoel nearly as long as body; stylet armature a sickle-shaped basis bearing about 9 minute conical stylets and 6 or more accessory stylet pouches; 16-22 proboscis nerves; 12-20 or more deeply branched and lobed intestinal diverticula; females with 4-13 pairs of ovaries; males with cluster of 5-8 spermaries each side of body in front of brain.
Distribution: Mostly trawled from depths between 350-1500 m, some individuals have been found in non-closing nets drawn to the surface from depths of 3500-3600 m. A widespread species, known from the Atlantic (off the west coast of Africa between the Gulf of Guinea and the Cape of Good Hope), Pacific (off Japan, east of the Kuril Islands, east of the Emperor Seamount Chain, in the submarine canyon off Monterey Bay, California, and near the Galapagos Islands), Indian Ocean (near Sri Lanka) and south of Australia where the Pacific, Indian and Antarctic oceans converge.