Abstract
The gall crabs belonging to the Family Cryptochiridae constitute a unique cryptic and little-known group of obligate symbionts of scleractinian corals (Anthozoa, Cnidaria). In Brazil, even with unique species making up the important national biodiversity (e.g. Opecarcinus hypostegus, Troglocarcinus corallicola, Troglocarcinus hirsutus and Kroppcarcinus siderastreicola) such associated fau…