(Lamarck, 1798)
Description
Adult. Difficult to distinguish from Alloteuthis medius. Body is slender, up to 210 mm long, with maximum mantle length of 140 mm; produced posteriorly to a finely tapered point; in males the portion posterior to the fins constitutes one-third to one-half total mantle length, in females less than one-quarter. Fins are narrow, rounded, together with a heart shape outline in dorsal view. [Variation in mantle shape: A.subulatus]. Width of the fin in adults is above 25 % of mantle length. Dorsal anterior edge of mantle produced as a quadrate projection extending between eyes. Arms up to twice length of head, with flattened, angular section, dorsal pair half length of ventral pair; all with two longitudinal series of suckers. Length of the longest arm in adults is 20-25 % of mantle length. Tentacle clubs are narrow with median suckers of middle region up to four times diameter of adjacent marginal suckers; suckers are attached obliquely to club axis at angle of about 45°.
Larvae/juvenile [hatchling A.subulatus-hatch]. Description not available. Generally no great changes in body forms occur in development from hatchling to adult. (Hanlon et al., in Sweeney et al., 1992).
Size
Adult mantle length maximum 14 cm; hatchling mantle length ca. 2 mm. [Synopsis of sizes of Alloteuthis species from hatchling to adult Loligo-sizes-y ].
Habitat
In coastal waters and offshore.
Distribution in the North Sea
All North Sea.
World distribution
E Atlantic, from the Shetland Island and S Norway to Cape Blanc (Mauretania) and the Mediterranean Sea.
Remark
As some authors regard Alloteuthis as a subgenus within Loligo, this would imply the present species to be Loligo (Alloteuthis ) subulata (Lamarck, 1798). More to read under Genus Alloteuthis.