Cuvier, 1797
Description
Larvae of 2.4 mm mantle length (not depicted): arms subequal, 4-6 suckers; arms with four chromatophores in one row; mid-dorsal region of mantle with two large posterior spots of one chromatophore each; ventral mantle with16-18 large chromatophores.
Juvenile of 6.0 mm mantle length (see right figure): arms subequal, 7 mm long, with 20-26 suckers; arms with 20-28 chromatophores in one row proximally and two rows distally; funnel with 2+2 chromatophores; mid-dorsal region of mantle clear, ventral mantle covered with 25-30 chromatophores.
Adult benthic [O.vulgaris ]. Adult body distinctly warty, up to 1000 mm total length, with maximum arm spread of 3000 mm, but commonly much smaller. Mantle aperture wide. Arms are thick and stout, bearing two longitudinal rows of suckers. Arm length is 70-85 % of total length.
Size
Mantle length of planktonic larva up to 6.0 mm, but 10.0-11.0 mm has been reported also. Adult total length up to 100 cm.
Depth range
Larvae and juveniles epipelagic; adults benthically on rocky coasts, from the shallow sublittoral to 100 m.
Distribution in the North Sea
Rare in the S North Sea, rare in the N North Sea.
World distribution
Cosmopolitan, widely distributed in warm and temperate waters of the E and W Atlantic Ocean, Mediterranean Sea, Carraibbean Sea, Mexican Gulf, and W Pacific. In the Atlantic Ocean, it reaches its NE limit in SW Britain and the W English Channel, where it varies in abundance from year to year.
[Description of larva after Hochberg et al., in Sweeney et al., 1992]