(Prosch, 1847)
Description
Adult. A sluggish squid with a coriaceous and firm mantle, which is fused with funnel and head in the occipital area. Mantle length up to 38 cm. Head is short and narrow. Eyes are very big and look aside. There is one tiny cartilaginous tubercle in each mantle- funnel fusion site. Dorsal (middle) component of funnel organ has three conical or finger-like papillae. Arms are strong and have two rows of suckers; there are several considerably enlarged suckers in distal part of lateral arms. Tentacles are long, with a slightly widened club bearing four rows of suckers with denticulate rings. In juveniles and adults anterior edges of fins are attached to lateral sides of mantle far ahead of the site of maximal width of the body. Posterior end of gladius is narrowly conical.
Juvenile. Mantle stout, saccular (< ca. 11 mm ML) [T.megalops-j ], becoming conical with growth, with large (if expanded), widely spaced, oval chromatophores [T.megalops-hatch ]. One tiny cartilaginous tubercle on each mantle- funnel fusion site, first seen at 30-60 mm mantle length. Head with short, stout arm-crown stalk. Eyes oval. Tentacles of medium length, usually stout, with four rows of suckers, extending nearly the entire length of the stalks. [After Roper and Sweeney, in Sweeney et al., 1992]
Size
Mantle length up to 38 cm.
Depth range
Adults mesopelagic and bathypelagic. Juveniles (6-20 mm mantle length) in 0-100 m layer; juveniles tend to live deeper with growth. There is evidence of diurnal vertical migration for juveniles and subadults.
Distribution in the North Sea
Occasionally northern North Sea, from the deep-waters of the Norwegian Sea.
World distribution
N Atlantic boreal-subtropical species; from SW Greenland, Denmark Strait, Faeroe-Iceland and Faeroe-Shetland Ridges and N Scotland to the Sargasso Sea and Canary Islands. Rarely found in Caribbean Sea.