The largest crustacean is the Japanese spider crab. The span of its legs can reach 3.7 meters, the cephalothorax is 40 centimeters long and the weight of an adult is about 19 kilograms.

An excerpt from the article 22 facts about crustacean

Their body is mostly red with white spots, which allows them to camouflage perfectly against the background of the ocean floor. Some individuals are completely red or white. They live exclusively around the Japanese coast around the island of Honshu and around the northeastern coast of Taiwan.