Infra-order Brachyura, Family Grapsidae
Pleated rock crab | Pachygrapsus plicatus (H. Milne Edwards, 1837)
A small-sized crab characterized by a carapace with many grooves and the grooved outer faces of the claws. Attains a carapace width of 20 mm. Variable in color ranging from off-white mottled with dark sage green, brown and black with light olive markings. Banded legs. Lower sections of walking legs have stiff spines and bristles.
Common at the water’s edge and lives along rocky intertidal shores exposed to the ocean.
Read more about Christmas Island's pleated rock crab in the book
"Crabs of Christmas Island" by Max Orchard
Pleated rock crab