Around 65 species of crab occur in the waters of the British Isles. All are marine, with the exception of the introduced Chinese mitten crab, "Eriocheir sinensis", which occurs in fresh and brackish water. They range in size from the deep-water species "Paromola cuvieri", which can reach a claw span of , to the pea crab, which is only wide and lives inside mussel shells.
Fisheries.
Several species of wild crab are the subject of crab fisheries around the coasts of the British Isles. The most important are the brown crab or edible crab, "Cancer pagurus" (29,193 t), various swimming crabs (3,180 t), the spider crab "Maja brachydactyla" (1,565 t), the shore crab or green crab "Carcinus maenas" (553 t) and the velvet crab "Necora puber" (193 t). Around 77% of the catch is landed in the United Kingdom, 19% in Ireland, 4% in the Channel Islands, and 1% in the Isle of Man.
Species.
62 species have been directly observed in the waters of the British Isles:
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Three deep-water species have also been recorded near the British Isles, and are likely to occur in the area. These are:
Notes.
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References.
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