The family contains about 19 species in three genera, widely distributed and plentiful in cold boreal waters of the Pacific Ocean.

Molecular studies in allozymes and mitochondrial DNA have indicated that this species nests within the genus Gonatus,[3] although other authorities treat it as a synonym of Gonatopsis okutanii.

[4] Morphologically, armhook squid are fairly uniform: all species are characterised by the suckers of their arms, which are arranged in four rows (series) rather than the typical count of two.

Only one species, the fiery armhook squid (Gonatus pyros), possesses photophores; these are located on the ventral periphery of the eyes.

Five female Gonatus onyx squids have been observed in Monterey Canyon dragging a membrane sack containing 2,000 to 3,000 developing eggs.