Hooks: 12-15; anterior teeth: 4-9; posterior teeth: 2-8.
Maximum adult body length: 23 mm; tail: 50-51 %.
Body large and firm, opaque; transversal musculature on trunk and tail; head very large; hooks not serrated. Fin bridge absent; one pair of medium length lateral fins both on trunk and tail; lateral fins without rays, rounded. Collarette absent; gut diverticula absent; eyes absent. Seminal vesicles conical; position of seminal vesicles: touching both posterior fins and tail fin. Ovaries short; ova fairly small. Adhesive papillae and adhesive organs absent. Vestibular organs small, with one row of papillae; apical gland cell complex present; neck canals absent.
Remarks: 6 immature specimens from about 4000 m in the Eastern North Atlantic.
Type locality: 20°N, 21°W.