A disease of corals. Colonies with this condition have small (2-10 cm diameter) circular to irregular patches of denuded skeleton that will increase in diameter an additional 1-10 cm over a period of 5-7 days. The disease typically affects the top surface of elkhorn coral (Acropora palmata) branches. In most cases most of the affected tissue dies rapidly, and subsequent enlargement of the bare skeletal areas slows after a few days and eventually stops. A bacterium has been identified as a causal agent .