Coconut Crab

The coconut crab is the largest land-dwelling arthropod in the world, found on islands across the Indian and Pacific Oceans, capable of growing to a leg span of nearly a metre and weighing up to about four kilograms. Related to hermit crabs, it uses a shell for protection only as a juvenile before developing a hardened abdomen as an adult that no longer needs a borrowed shell, and it has extraordinarily powerful claws capable of exerting one of the strongest pinching forces measured in any animal, strong enough to crack open coconuts, from which it gets its common name, although its diet also includes fruit, carrion and other organic matter. Coconut crabs breathe using a specialized organ that is intermediate between gills and lungs, allowing them to live entirely on land as adults, though they must still return to the ocean to release their eggs, which hatch and develop through a larval stage in the sea before young crabs return to shore. Slow to mature and long-lived, with some individuals estimated to live for several decades, the species has declined in many areas due to habitat loss and hunting for food, and it is now protected in several island nations.