Characters: Colonies are encrusting plates or thick ridges, columns or branches. Branches are usually upright, but are commonly horizontal or irregular in shape, depending on exposure to wave action. There are usually no axial corallites. Corallites are smooth, rounded and exsert. The coenosteum is composed of fine spinules with elaborated tips.

Colour: Pale cream or brown.

Similar Species: Isopora cuneata, which has smaller, flatter branches and finer, more rounded, less elongate corallites. These species are difficult to distinguish unless they occur together. See also I. elizabethensis.

Habitat: Occurs in all reef environments.

Abundance: The most abundant coral of the northern Great Barrier Reef where it is the dominant species of most exposed outer reef slopes. Usually less dominant elsewhere in Australia and most other countries.