A pale crab freckled with reddish spots, carrying claws noticeably longer than its walking legs, up to about 2 cm (0.8 in) across. It lives on black corals and gorgonians rather than on stony coral, which puts it deeper than most of the reef's symbiotic crabs.
The long claws are for the host's own defence as much as its own: like the guard crabs of the shallows, this species drives away animals that would graze the colony, and takes mucus and trapped particles in return. Black coral bushes grow on shaded walls and overhangs below about 10 m (33 ft), and a careful torch pass over one often turns up a pair of crabs, a squat lobster and a shrimp on the same branch. Records here are few, though that reflects how rarely divers examine black coral closely rather than genuine scarcity.
- pale body marked with reddish spots
- long slender claws, longer than the legs
- found on black coral bushes, not on stony coral
- width up to 2 cm
