Colonies are a network of anastomosing branches, either compacted or open, and up to 5 metres across in lagoons with soft substrates. Branches are triangular in section. Valleys are short and shallow with thick columellae and septa which, except near branch tips, are fused into one solid structure. Tentacles may be extended during the day. There is little or no development of an encrusting base and no development of laminae.
Pale yellow or cream.
Reef environments protected from strong wave action.