Filippova, 1972
Mantle soft, not very muscular, conical, with short tail in adults. Fins transverse-oval in larvae and juveniles, widely heart-shaped without tapering end in adults; fin length in adults approx. 40%, width approx. 50-60% ML. Arms and tentacles very long and weak, arm length approx. equal to ML. Club in adults with 30-40 (usually 32-33) hooks and 6-10 rows of suckers on dactylus. Surface of mantle and head with soft longitudinal skin ridges or papillae, even in early larvae (ML 3-5 mm). Gladius not visible from dorsal, with short (usually not more than 10% ML), triangular, cartilaginous rostrum posteriorly. No nuchal folds, no photophores. ML up to 100 (115?) cm.