Chaetodon citrinellus, also known as the Speckled Butterflyfish or Citron Butterflyfish is very common in the Pacific from the coast of East Africa to the Hawaiian, Marquesan and Tuamoto islands, north to southern Japan and the Ogasawara Islands, south to New South Wales (Australia) and Lord Howe Island.
The Citron Butterflyfish is a delicate cream to pale yellow, covered with small spots. It has a black stripe through the eye and over the head to the dorsal fin origin, the caudal fin is transparent. There is also a thick black band along the anal fin margin. The black lower anal fin margin distinguishes it from other species.. Small juveniles settle in ledges with urchins commonly mix with other similar sized juveniles like C. kleinii; adults may be solo, in pairs or small groups. Chaetodon citrinellus grows to 13cm (5.1 in.) in length. He is to be found in shallow exposed reef flats, lagoons, and seaward reefs; in relatively open areas with scattered corals.
Butterflyfish are not recommended for reefs as they will pick at or eat a wide variety of corals, fan worms, and other invertebrates. Most Butterflyfish are known to pick at Aiptaisia, a parasitic anemone.