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''Cancer pagurus'', commonly known as the edible crab or brown crab, is a species of crab found in the North Sea, North Atlantic Ocean and perhaps in the Mediterranean Sea. It is a robust crab of a reddish-brown colour, having an oval carapace with a characteristic "pie crust" edge and black tips to the claws. A mature adult may have a carapace width of up to and weigh up to . ''C. pagurus'' is a nocturnal predator, targeting a range of molluscs and crustaceans. It is the subject of the largest crab fishery in Western Europe, centred on the coasts of the British Isles, with more than 60,000 tonnes caught annually. ==Description== The carapace of ''C. pagurus'' adults is a reddish-brown colour, while in young specimens it is purple-brown. It occasionally bears white patches, and is shaped along the front edge into nine rounded lobes,〔 resembling a pie crust.〔 Males typically have a carapace long, and females long, although they may reach up to long in exceptional cases.〔 Carapace width is typically , or exceptionally up to . A fold of the carapace extends ventrally to constitute a branchial chamber where the gills lie. The first pereiopod is modified into a strong cheliped (claw-bearing leg): the claw's fingers, the dactylus and propodus, are black at the tips.〔 The other pereiopods are covered with rows of short stiff setae; the dactylus of each is black towards the tip, and ends in a sharp point.〔 From the front, the antennae and antennules are visible. Beside these there are the orbits in which the eyes are situated.〔 The mouthparts comprise three pairs of maxillipeds, behind which there are a pair of maxillae, a pair of maxillules, and finally the mandibles.〔 In common with most crabs, the abdomen is folded under the thorax and shows clear sexual dimorphism: in males it is comparatively narrow, whereas in the female it is wider.〔 抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』 ■ウィキペディアで「Cancer pagurus」の詳細全文を読む スポンサード リンク
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