Colonies are digitate. Branches are thick, tapering to large dome-shaped axial corallites. Small branchlets or incipient axial corallites usually occur at the base of main branches. Radial corallites are of two sizes, the larger are usually in rows and have thick walls and only slightly increase in size down the sides of branches.
Many colours, but most usually cream, brown, purple or blue (which may photograph purple) with blue or cream tips.
Exposed upper reef slopes and reef flats.
Usually common, and sometimes a dominant species.