Hooks: 6-9; anterior teeth: 10-13; posterior teeth: none.
Maximum adult body length: 16 mm; tail: 30-40 %.
Body slender; transversal musculature absent; head fairly large; hooks not serrated. Fin bridge absent; one pair of short lateral fins both on trunk and tail; posterior fins short, partially rayed or no rays, rounded. Collarette absent; gut diverticula absent. Small eyes with star-shaped pigment spot. Seminal vesicles with knob and trunk; position of seminal vesicles: touching both posterior fins and tail fin. Ovaries short; ova fairly large. Adhesive papillae and adhesive organs absent. Apical glands absent.
Distribution: epi- and mesopelagic; global between 40°N and 40°S.
Remarks: very prominent anterior teeth.
Type locality: Bay of Naples, Mediterranean.