The biological classification is different: the king crab refers to the giant quasi-shore crab, which belongs to the decapod and short-tailed fan crab family. King crab, also known as stone crab or rock crab, is a crustacean of the family Stone Crab.

Different shapes: the king crab has four pairs of feet and a pair of crab claws, while the king crab has only three pairs of feet and a pair of crab claws.