Coconut Crab

• récordIt is the largest land arthropod in the world, and will climb trees to cut coconuts loose with its powerful claws before dropping them to break on the ground.
• Its claws exert one of the highest gripping forces measured in the animal kingdom, enough to crack open a coconut.
• It is so adapted to life on land that it drowns if submerged: it breathes with branchiostegal lungs that it has to keep moist.
• Its larvae are marine: the females come down to the shore to release them, and the young spend their first weeks at sea, in a borrowed shell, before coming ashore for good.
• It is the largest land arthropod in the world: up to a metre across the legs and about 4 kg.
• Its claw is the strongest measured in a land animal: up to some 3,300 newtons in the biggest specimens, a force that far exceeds the bite of most vertebrates and lets it open coconuts.
• It is a hermit crab that gave up the shell. When young it occupies snail shells like any hermit crab, but as it grows it hardens its own abdomen and does without them for good.
• It cannot swim: as an adult it breathes with branchiostegal lungs, a rudimentary kind of lung, and it drowns if submerged. The only exception is the female, who goes down to the shore to release her eggs into the sea.
• Its sense of smell is extraordinary and works in air, not in water: it has remodelled its olfactory organs into a design closer to that of insects, and it detects rotting fruit and carrion from kilometres away.
• It can live sixty years and takes about five to mature, which makes it very vulnerable to overexploitation; it is listed as Vulnerable.
• It has been suspected for decades of being the cause of the disappearance of Amelia Earhart's remains on the island of Nikumaroro, though that is only a hypothesis.

Skeleton type

Invertebrate - chitin exoskeleton (crustacean)

Habitat and environment

Coastal forest and scrub on Indo-Pacific islands and atolls

Sexual maturity

5 years

Sources consulted: Wikipedia (es): Birgus latro