FAMILY GONATIDAE HOYLE, 1886

(19 SPECIES IN FOUR GENERA)

Diagnosis: Medium adult-sized muscular Oegopsida with buccal connectives attached to the ventral borders of ventral arms; with four series of arm suckers, usually with hooks in the two medial series of dorsal, dorsolateral and ventrolateral arms; tentacles with numerous irregular series of suckers, sometimes with hooks, funnel–mantle locking apparatus straight, reaching the anterior margin of the mantle; usually without photophores; gladius with primary conus; egg masses brooded by females.

Remarks: This family has a wide range of variation within several key characters. The genera Gonatus Gray, 1849 and Eogonatus Nesis, 1972 have a modified carpal locking apparatus with elongated ridges, suckers and knobs at the base of the manus. The genus Berryteuthis Naef, 1921 has no hooks on tentacular clubs, whereas Gonatopsis Sasaki, 1920 loses its tentacles in the early juvenile stage. Gonatus pyrus Young, 1972 has ocular photophores.