Characters: Colonies are massive, forming lobed to columnar colonies. Corallites are flattened, of similar size, 2-3mm diameter, formed by extratentacular budding. Septa are in two unequal orders, first order septa forming a small columella. Walls are composed of thickened septa. Costae are conspicuous and regularly dentated.
Colour: Brown or yellowish.
Similar Species: Orbicella franksi has an irregular surface, is more calcified and has more prominent costae. Orbicella faveolata is less calcified, with more uniform corallites with thin costae.
Habitat: Most reef environments.
Abundance: Common, frequently a dominant species of lagoons and upper reef slopes.
Taxonomic Note: Formerly in genus Montastraea.
Taxonomic References: Laborel (1969); Roos (1971); Zlatarski and Estalella (1982); Veron (2000a); Medina, Weil and Szmant (1999); Budd, Fukami, Smith et al. (2012);
Identification Guides: Humann (2002);