Mantle cylindro-conical, narrowed behind, head not retractable. Fin heart-shaped, with tapering end. Ventral protective membranes on 3rd arms not widened. Rings of large club suckers with one long tooth in the centre of distal side, others smaller. Fixing apparatus with knobs and suckers. Funnel pit with foveola, longitudinal ridges, and usually side pockets. Funnel and mantle cartilages fused. Photophores: 1 each on ventral side of eyeball; 1 each in middle and near base of 4th arms; two long narrow luminous stripes on ventral mantle along the sides of ventral midline from anterior to posterior end, interrupted near anterior end and near line of maximal fin width; many tiny simple photophores dispersed on skin of mantle; one in mantle cavity on gut at boundary between middle and posterior third of length. No dorsal photophore. ML up to 22 cm. Larvae: proboscis rather long, 1/2-2/3 ML, in early larvae longer, in later shorter than arms; lateral suckers on tip up to 1.5 times larger than others. Proboscis beginning split at ML approx. 5-5.5 mm, finishing at 9-10. Fourth arm pair developed at ML approx. 2 mm. Mantle narrow. Funnel and mantle cartilages fused at ML approx. 8-11 mm. Eyeball photophores at ML approx. 3.5 mm, gut photophore at 3-3.5 mm, luminous stripes on the mantle at ML approx. 20 mm. Single gut photophore and luminous stripes are characteristic features. Mantle in larvae with dispersed large brown chromatophores, in juveniles with crimson and brown chromatophores.
One species with disjunct range of bi-peripheral type: N and S Pacific, South Atlantic, and S Indian Ocean.