Habitat: In mangrove, seagrass, artificial substrate, under rock or coral; common in patch reef and in the posterior zone of the reef. Distribution: Caribbean wide. Characteristics: Massive-amorphous to ramose, black to dark green externally, black with yellow tinges internally. Surface varies from smooth, to tuberculate to conulose. Oscules raised above the body (3-10 mm in diameter). Compressible to the touch. Smooth surface, with detachable skin.