Characters: Colonies are massive and occasionally occur as free-living mobile balls. Corallites are rounded and shallow, 2.5-3.5 millimetres diameter. Septa have curved upper margins and are granulated. Most are not fused and do not form distinct cycles. Columellae consist of one or a few granules.
Colour: Reddish-brown with pale walls.
Similar species: Superficially similar to Siderastrea radians but corallite characters are more like S. savignyana.