Coconut Crab

The coconut crab (Birgus latro) is the largest land-living arthropod, with a leg span of up to about a meter and a weight of several kilograms. It lives on islands of the Indian and Pacific oceans and is a giant hermit crab that no longer uses a shell as an adult.

🧬 Field Guide Specimen: Open Coconut Crab in the CRV Science Field Guide to log the specimen, see its place among the Ecdysozoa lineages in the Cladogram Explorer, and test your recall in the Red List conservation game.

Adults have lungs-like organs in the gill chamber and will drown if immersed in water for long. Females release their larvae into the sea, where they drift as plankton before the young crabs come ashore and use snail shells for a time.

The crab climbs palms and uses its massive claws to open coconuts, sometimes after husking them. A measured pinch force of more than a thousand newtons is among the strongest of any land animal.

Coconut crabs grow slowly and take decades to reach full size, so hunting for food and habitat loss have wiped them out from some islands. The species is a good example of island gigantism.

• Giant Isopod — another giant crustacean
• Sea-level rise — a threat to island habitats