(Brinkmann, 1917a)
Body large when mature, without caudal fin, more slender and thicker than most bathypelagic nemertines; lengths of 7-105 mm, widths up to 35 mm and a thickness of 10 mm are reported; rhynchocoel nearly as long as body; stylet armature comprising a slender but sharply curved basis bearing many sharply conical stylets, with 6 pouches of accessory stylets; 23-29 proboscis nerves; 30-40 pairs of profusely branched intestinal diverticula, branches extending laterally above and below lateral nerve cords; females with about 30 pairs of ovaries; males unknown.
Distribution: First taken in non-closing nets drawn to the surface from a depth of 2000 m, this species has been subsequently trawled from between 1000-2500 m; one specimen obtained in a net where the water depth was 4400-4800 m but "it is probable [this] specimen was caught nearer the surface" (Coe, 1954a: 236). Recorded from the North Atlantic (West European Basin, southwest of Ireland, and in the Bermuda region), the South Atlantic (in an area between 33º-34ºS and 4º-16ºE near the Tristan da Cunha Islands) and the North Pacific (south of Alaska between 48º37'-48º58'N and 157º29'-157º50'W).