Characters: Colonies are submassive or encrusting, with an irregular surface. Corallites are small and often crowded. Septa are in two unequal orders of 12 each, the first being exsert and irregularly toothed. Coenosteum spinules are prominent. ‘Groove and tubercle’ formations are often present. Colonies are often infested with parasitic barnacles. Colour: Mottled cream or yellowish-green, sometimes mottled grey. Similar species: Cyphastrea chalcidicum, which has strongly alternating costae. See also C. ocellina. Habitat: Shallow exposed reef environments. Abundance: Usually uncommon.