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- Cephalopods are a class of free-living predatory animals characterized by bilateral (two-sided) symmetry. The body of the mollusk is divided into a head and a trunk. On the head there are arms and tentacles surrounding the mouth opening. The mouth is small, the pharynx is muscular, and in the throat there is a horny beak. The arms are covered with numerous disk-like suckers. Squids have suckers which are also equipped with hooks used to capture and retain the prey. Cephalopods of the Barents Sea have 8 arms, cuttlefish and squids have an additional pair of tentacles. There are a pair of large eyes on the sides of their head. The trunk with the internal organs is covered with a mantle. Squids live in the water column, cuttlefish and octopuses mainly live in the benthic, although some species live in the pelagic zone. The main food for cephalopods is fish, crabs and molluscs (Nesis, 1976, 1982).
In the Barents Sea cephalopods are represented by 9 - 11 species: 3 species of squids, 3 species of cuttlefish and 3-5 octopuses. Due to the complexity of the species identification of octopods, it is recommended that they can be classified to the genera Bathypolypus or Muusoctopus. Among the cuttlefish, Rossia palpebrosa is the most common species in the Barents Sea, however the second species - R. moelleri prefers the cold-water areas in the north of the Barents Sea and the Kara Sea. Among squids, Gonatus fabricii constantly inhabits the Barents Sea; other species are encountered during the warming season.
The appearance of a squid (according to Nesis, 1976): 1 - mace tentacles, 2 - tentacles, 3 - arm, 4 - beak, 5 - suckers, 6 - oral membrane, 7 - head, 8 - eye, 9 - funnel, 10 - front edge of the mantle, 11 - trunk, 12 - fin, 13 - mantle hole
Cartogram of biomass distribution of Cephalopoda (kg / mile of trawling)0 votedJanuary 25, 20181

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