Characters: Colonies consist of a tangle of branches which are usually twisted into irregular shapes. Branchlets are uncommon. Axial corallites are tubular; incipient axial corallites occur irregularly. Radial corallites are irregular and immersed to tubular, giving branch surfaces a rough appearance.
Colour: Grey or tan.
Similar Species: None. Isopora brueggemanni has thicker and more uniform branches and larger and more regularly arranged radial corallites. Acropora roseni has similarly irregular radial corallites.
Habitat: Shallow reef environments.
Abundance: Uncommon.
Taxonomic Note: Although the species illustrated here is distinct, there is doubt over the designation of this name. The holotype of Acropora meridiana Nemenzo, 1971 has previously been considered a synonym of Isopora brueggemanni by Wallace (1999) and Wallace, Done and Muir (2012). As illustrated here, most colonies have gnarled basal branches without clearly distinguishing characters, consistent with Nemenzo's type. Further detailed study is warranted.
Taxonomic References: Nemenzo (1971); Veron (2000a);
