Colonies are composed of large, tapered, prostrate branches. Axial corallites are dome-shaped with small openings. Radial corallites occur only on the upper surfaces of branches; lower surfaces are smooth. They are of mixed sizes, the smallest are immersed, the largest are bead-like, up to 4 millimetres diameter. All corallites have small openings. The coenosteum is smooth and dense, composed of fine spinules without elaborated tips.