Tetra a tall dorsal fin characterized by a short connection to the fish’s body. Additionally, tetras possess a long anal fin stretching from a position just posterior of the dorsal fin and ending on the ventral caudal peduncle, and a small, fleshy adipose fin located dorsally between the dorsal and caudal fins. This adipose fin represents the fourth unpaired fin on the fish (the four unpaired fins are the caudal fin, dorsal fin, anal fin, and adipose fin), lending to the name tetra, which is Greek for four. While this adipose fin is generally considered the distinguishing feature, some tetras (such
Upeneus moluccensis anal fin. The caudal fin is deeply forked. The chin bears a pair of barbels which do not extend past the margin of the preoperculum. The upper and lower jaws, the palatine and the vomer are covered in brush-like or villiform teeth. The back is pinkish-red in colour contrasting with the white belly, from which it is separated by single longitudinal yellow stripe which runs from the operculum to the caudal fin peduncle. The dorsal fins are yellow in colour with 3 parallel red bars while the pectoral find is a similar colour but lacks markings and the pectoral fin