Also known as Beachrunner Crab, Blackback Land Crab, Black-backed Land Crab, Black Land Crab, Brachyura Crab, Little Nipper, Purple-backed Shore Crab, Terrestrial Crab, Tropical Land Crab, True Crab.
Found on the land under coconut husks and leaf litter, over sandy areas in and around coconut trees, mangroves and shorelines.
They feed on detritus, plants and seedlings.
Length - 11cm
Depth - Land
Widespread Indo-West Pacific
These crabs have evolved over millions of years to live on the land, however when they are ready to spawn they ventures to the edge of the shore to release their eggs.
The juveniles then go through several moults underwater before the last critical moult to become a terrestrial crab, leaving the water back to land.
Brachyura crabs are considered true crabs, they have a short abdomen, 4 walking legs and a pair of clawed arms at the front.
Many thousands of species live worldwide in sea water, fresh water and on land. Ref: https://www.sealifebase.org/summary/Geograpsus-grayi.html