Japanese Spider Crab

The Japanese spider crab is a species of marine crab native to the waters around Japan, holding the record for the largest leg span of any living arthropod, which can exceed three metres from claw to claw in mature individuals. Its body is comparatively small relative to its long, spindly legs, and its shell is covered in small bumps and hook-like structures onto which it often attaches sponges, algae and other debris as camouflage against predators. It lives on the sandy and rocky seafloor at depths that can range from around fifty to several hundred metres, moving into shallower waters seasonally to breed, and it feeds as a scavenger on dead animal matter, algae and small invertebrates. Like other crustaceans, it grows by periodically molting its hard exoskeleton, a vulnerable process during which it hides to avoid predation. Though slow-moving and not aggressive, its long lifespan, which can reach a century, and enormous size have made it a notable attraction in public aquariums worldwide, and it is also harvested as a food source in parts of Japan.