Common octopus

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Common octopus
Common octopus (Octopus vulgaris)

Common octopus ( Octopus vulgaris )

Systematics
Subclass : Octopus (coleoidea)
Superordinate : Eight-armed squid (Vampyropoda)
Order : Octopus (octopoda)
Family : Real octopus (Octopodidae)
Genre : Octopus ( Octopus )
Type : Common octopus
Scientific name
Octopus vulgaris
Cuvier , 1797

The common octopus or common octopus ( Octopus vulgaris ), sometimes only called octopus (plural octopods ), is a large cephalopod from the order of the octopus .

features

Locomotion of a Common Octopus

The pallium (the mantle-like back surface) of the common octopus has a wide opening and is up to 25 centimeters long; the tentacles reach a length of up to one meter and are equipped with two rows of suction cups. The dorsal (back) arms are the shortest. The lateral (side) arms are longer than the ventral (front), the ventrolateral arms are only slightly longer than the dorsolateral arms. The sipho is W-shaped. An ink sack is available. The common octopus has no ocelli (point eyes) between the eyes and the base of the lateral arms. The common octopus has no shell. This enables him to be highly mobile and enables him to squeeze through the narrowest of openings.

Distribution area

The common octopus is found in tropical and temperate seas around the world, most commonly near Great Britain and the Southeast Asian coast. The common octopus sensu stricto is possibly only distributed in European and North African waters, while the remaining populations are representatives of at least four species that can not be distinguished morphologically from the common octopus. The differentiation is only possible through molecular genetic studies, and the first description of the species in question is still pending.

The species colonizes the benthos from the coast to the outer edge of the continental shelves at depths of up to 200 meters, where the common octopus finds a variety of habitats such as rocks, coral reefs and seagrass beds.

Systematics

Evidence of Octopus vulgaris is available from all oceans, whereby the systematists agree that it is a species complex . The relationships between the individual populations have not yet been further investigated.

Nutrition and reproduction

The common octopus feeds mainly on crustaceans (crabs and lobster-like) and molluscs (clams and snails).

Females produce between 120,000 and 400,000 eggs, which are laid in strings, especially in crevices and caves in shallow waters. The laying of eggs can take up to a month. During the breeding season (25–65 days, depending on the water temperature) the females eat almost no food, which is why many die after the paralarvae hatch. The developing octopus (Paralarve) is planktonic.

The common octopus lives up to two years in the wild, but can live up to three years in captivity under optimal housing conditions.

fishing

The common octopus is caught primarily for human consumption and sold as freshly caught, frozen or dried and salted. According to the Food and Agriculture Organization , 34,262 tons were caught in 1999, with Mexico catching the largest at 19,081 and Italy at 8,844 tons.

In general, catches have been falling since the late 1960s. At that time, more than 100,000 tons were caught per year.

proof

  1. weichtiere.at Kraken Status: May 1st, 2008
  2. ^ Mark D. Norman, Julian K. Finn, FG Hochberg: Family Octopodidae . In: Patrizia Jereb, Clyde FE Roper, Mark D. Norman, Julian K. Finn (Eds.): Cephalopods of the world. An annotated and illustrated catalog of cephalopod species known to date (=  FAO Species Catalog for Fishery Purposes . Volume 3 , no. 4 ). Volume 3. Octopods and Vampire Squids. FAO, Rome 2014, ISBN 978-92-5107989-8 , pp. 36–215 , here pp. 40-47 ( fao.org [PDF; 26.3 MB ]).
  3. Oktopous oracle Paul Age expectation Kraken as of July 10, 2010
  • Michael Hutchins (Ed.): Grzimek's Animal Life Encyclopedia, 2nd edition. Volume 2, Protostomes , Farmington Hills, MI: Gale Group, 2003.

Web links

Commons : Octopus vulgaris  - album with pictures, videos and audio files