White-breasted spiny tailfish, also known as pink blue hanging, pink blue upside down hanging, is a genus of spiny tail fish in the suborder Spiny tail of the suborder Spiny Tail fish, which is a tropical marine fish active offshore. Distributed in the indian ocean and the central and western Pacific Oceans, although they live near reef areas, they are not strictly coral reef fish, and their activities are more extensive. Its beautiful appearance can be used as an ornamental fish, and it is the most representative species of spiny tailfish.
The body is oval in shape and flattened laterally. Small mouth, terminal position. The whole body is powder blue or royal blue, and the body color is dark and light. The dorsal fin is bright yellow with a black rim; the pectoral fin is yellow; the ventral fin and fin are pale blue, and there are several dark gray vertical ring bands on the side of the body. The head is triangular and dark blue-black. The eyes are close to the top of the head, there is a white line on the lip margin, and a white marking from the throat cheek to the posterior edge of the gill cap. The caudal fin is forked, white, with black edges, and a pale white or pale yellow spiny tail hook on each side of the tail stalk.
The general body length is 23 cm, and the maximum body length is recorded to be up to 54 cm. Hot-tempered, very active, and swims very fast. When threatened, it will swing its tail from side to side and attack enemies with thorns on the tail handle. They generally act alone or in pairs, practicing monogamy and gathering into large schools of fish when foraging. When disturbed, they will hide in caves or crevices in the reef disk. Herbivorous, feeding on sparsely dispersed algae on the seafloor.