Blue king crab

The blue king crab (Callinectes sapidus) is a decapod crustacean of the family Portunidae. The species measures up to 15 cm long and 23 cm wide. It has a more than long, elliptical body, with two spikes on either side of the body and a serrated anterior margin. The legs are rather elongated with the first pair turning into claws, larger in males than in females. The colour of the body is olive-green on the upper side, while the green is blue-white and the legs have a deep blue colour at the junction and end. During the moulting period, pink spots appear on the last pair of legs, which become increasingly red as the moult approaches. (Source: wikipedia).