Characters: Polyps are circular, up to 200 millimetres diameter and flat or with a central dome. Septa are of markedly different sizes and have large triangular to columnar teeth with a central rib and which form a regular pattern. Tentacular lobes are usually not developed. Costae are widely spaced, the larger having simple spines. The undersurface has pits between the costae.
Colour: Brown, sometimes with radiating stripes, with white tentacular lobes.
Habitat: Reef slopes and lagoons.
Abundance: Common in the western Indian Ocean and Red Sea, uncommon elsewhere.
Source reference: Veron (2000). Taxonomic reference: Veron and Pichon (1980). Additional identification guides: Veron (1986), Sheppard and Sheppard (1991), Nishihira and Veron (1995).