Characters: Colonies are large and hemispherical or encrusting. Valleys are usually long and sinuous but may become short, with 1-3 centres and form Hydnophora-like (Merulinidae) monticules. Septa are exsert, equal, and finely toothed. A fine ambulacral groove occurs along the tops of walls. Tentacles are extended only at night. Colour: Walls are brown or grey with valleys the same colour or green. Similar species: Manicina areolata. Valleys are similar in size to Oulophyllia of the Indo-Pacific. Diploria species have smaller valleys and skeletal structures. Habitat: Shallow reef environments. Abundance: Sometimes common, conspicuous