Furry Coral Crab (Cymo melanodactylus)
…a small species of pebble crab that is distributed throughout the Indo-Pacific, extending from the Red Sea and Madagascar to New Caledonia and French Polynesia. Furry coral crabs are found in coral reefs and exclusively live on the surface of corals in the genus Acropora. C.melanodactylus are commensal organisms for Acropora spp as 2-3 individuals will live on the coral and protect them from predators. In turn the crabs get to nibble on the coral’s mucus secretions, which causes the coral little harm. Although they primarily eat mucus furry coral crabs are also known to eat zooplaknton, organic particles and even some of the coral’s living tissue.
Furry coral crabs are often found in larger numbers on dead/damaged corals, its currently unknown weather they are the cause of it or if they are merely exploiting it. A recent study has shown that C.melanodactylus that are attached to corals with white band disease actually cause the disease to advance at a much slower rate than if they were absent.