Spider crab introduction: The Japanese giant spider crab lives on the seabed in the southeastern coastal waters of Japan. It is the largest animal in the Crustacea, with a body length of 30-50 cm. When the entire chelicerae is fully extended, it can reach 3.7 meters. . Like other crustaceans, it also sheds its shell, and each molt takes about 36 hours. Its molting process is not complicated. When the crab shell splits longitudinally, its body will come out of the shell first, and the crab legs will come out last.