Mantle cylindrical in anterior and conical in posterior part, semigelatinous. Fin large, round, oval, heart- or diamond-shaped, usually longer than half of mantle. Arms with 2 rows of suckers, 4th usually much longer than others. Tentacles extremely long, whip-like, with thin stem and barely widened club bearing minute suckers in many rows. No keel nor fixing apparatus. In some species tentacles autotomized during capture. Buccal membrane with 7 lappets, connectives to 4th arms attached ventrally. Funnel cartilage ear-shaped or oval, usually with 2 projections: tragus (on ventral side) and antitragus (on posterior side), rarely with 3 or none. Mantle cartilage nose-like or consists of 2 short ridges forming a right angle. Gladius narrow, with long conus, reaching far behind posterior end of fin and forming a tail thread. Photophores in various positions, may be on eyeball, on eyelid ventral to eye sinus, on ventral side of mantle, fin, funnel and 4th arms, absent in some species. Development gradual, without clear larval stage. Three genera.
Planctonic stages recorded for: