Sea Fan Disease Key

Sea fans (Gorgonia spp.) are very visible members of the coral reef community. The fans rise above the reef structure and filter small prey from the passing water. Two diseases of sea fans are presented here. Both are characterized by the discoloration of the gorgonian tissue. The affected areas of the sea fan may appear as patches of darker purple, with other patches where the axial skeleton of the sea fan is bare. Both diseases involve the presence of extraneous filamentous material on the fan.

If there is discoloration of the sea fan in a distinct band or patches: