Indo-West Pacific: Maldives to New Ireland in Papua New Guinea, including Cocos-Keeling Islands, north to Ryukyu Islands and south to the Philippines, including Palau. This species is the terminal male of Scarus singaporensis. Possibly replaced by Scarus falcipinnis in the western Indian Ocean.

Median predorsal scales 6; 3 scale rows on cheek, with 1-3 scales in ventral row. Caudal fins emarginate in initial phase to deeply concave in large terminal phase. Lips nearly covering dental plates; terminal males with 0-2 canines posteriorly on side of upper plate, none on lower. The initial phase closely resembles that of S. altipinnis. The terminal phase has the distinctive brilliant green throat and lacks the filamentous middle dorsal spine.

Usually associated with outer reefs but will enter shallow water in protected areas.