Small Knob Coral

About

Small Knob Coral (Astrea devantieri) is a massive, boulder-forming species native to the shallow reefs of the western Indian Ocean, with a documented range spanning Iran, Somalia, and Yemen. In the wild it occupies reef environments from the surface down to around 30 metres, forming smooth, dome-shaped colonies that can eventually reach boulder proportions. The individual corallites are small and neatly uniform, measuring just a few millimetres across, with well-defined walls and septa arranged in two clear orders. A detail that helps distinguish it from looser, more irregular relatives. Colouration is one of its most recognizable traits: the tissue typically runs red to orange with contrasting green centres, giving the colony a patterned, almost mosaic-like appearance rather than a flat wash of colour. In the aquarium, this species sits comfortably in the intermediate care category. It appreciates moderate lighting and moderate water movement, conditions that broadly mirror its natural shallow-reef habitat. It is considered reef safe and poses no particular threat to neighbouring corals through sweeper tentacles or aggressive growth, though like most Astrea species it benefits from stable water quality and consistent parameters over time. Availability in the hobby tends to be limited given its relatively restricted natural range, which makes it a worthwhile find for keepers looking to represent some of the Indian Ocean's less commonly kept reef builders.