Kristensen, 1981
Description
Adult. Mantle slender, obviously conical; head appears to be strong and dominant. Tentacles are long and strong. One row of suckers along the ventral edge of tentacular stalk. Club is short, its length 13-17 % of mantle length [G.steenstrupi-t ]. In addition to the central hook in the club, a distal and usually four or more small proximal hooks are present; central hook is very large and sharp. There are 9-13 transverse rows of suckers and hooks in the basal half of the third arm; 14-17 transverse rows of suckers in the basal half of the fourth arm. Fin is heart-shaped, passing beyond the posterior end of the mantle.
Radula: lateral teeth of radula with ridge on the base plate.
The ratio of tentacle club length and pen length ranges from 0.20 to 0.36.
Young unknown.
Size
Maximum mantle length 35 cm.
Depth range
Adult in the lower epipelagic and mesopelagic zone; sometimes (but rarely) migrating to the surface at night. Also living at the bottom on the slopes. Larvae and juveniles live in the epipelagic zone.
Distribution in the North Sea
Possibly entering the northern North Sea from the adjacent Norwegian Sea.
World distribution
Mainly EN Atlantic 45-63°N; widely distributed in the boreal zone of the N Atlantic. The type locality is Rockall, west off the British Isles.
The distributions of eastern G. steenstrupi and western Gonatus fabricii overlap in the Irminger Sea.
[After Kristensen, 1981]