Characters: Colonies have a branching growth-form. They may form compact hemispherical mounds or thickets over 2 metres across or occur as a few isolated branches. Corallites are monocentric or form short valleys. Walls are thick, rounded and smooth. Columellae are absent. Tentacles are extended only at night.
Colour: Grey-green to brown.
Similar Species: Australogyra zelli is similar to Platygyra in corallite structure but not growth-form. Goniastrea ramosa has a similar appearance but is much smaller and has paliform lobes.
Habitat: Usually in turbid waters around high islands or in reef lagoons.
Abundance: Uncommon.
Taxonomic Note: Very distinct species.
Taxonomic References: Veron, Pichon and Wijsman-Best (1977) as Platygyra zelli; Veron (2000a); Huang, Benzoni, Fukami et al. (2014); Arrigoni, Berumen, Terraneo et al. (2014);
Identification Guides: Veron (1986a);