Nomes alternativos: blue demoiselle, Chrysiptera cyanea, blue devil, cornflower sergeant-major, Hedley's damselfish, red tail Australian damsel, sapphire devil, sky-blue damsel
The blue damselfish are small fish of a dazzling blue color. The fish are native to the Indo-Pacific, where they inhabit reefs and lagoons.
A specimen can reach 8.5 cm in length. Although small, it is known for its aggressive temper as it's very territorial.