Gyrosmilia interrupta (Ehrenberg 1834)

zooxanthellate

Colonies are up to 30 cm across. They are encrusting, rarely attaining a height of over 3 cm. Valleys are about 8 mm wide or less, and septa of adjacent valleys often join at the top of the thin wall, where their line of contact is marked by a thin ridge. Septa curve slightly laterally, and have a radius over the top of the wall of 2-3 mm. They plunge steeply, and there is no columella. The species is common at mid- to deep depths on all reef slopes. The species prefers recesses and small holes in the reef, which makes it more inconspicuous although it is fairly abundant. It is found equally commonly in moderately turbid as well as clear water reef slopes. Living corals are always shades of brown. Tentacles are retracted during the day. (Sheppard, 1998 ) Colonies are circular and slightly domed, have meandering radiating valleys. The light skeleton has the enlarged septa found in Plerogyra and Physogyra, but lacks their characteristic vesicles. Colour: usually a chocolate brown, occasionally with a greenish hue. Habitat: diverse. (Richmond, 1997)