Piranha pomfret has an ovoid body, laterally compressed, and the caudal fin is again shaped. The body is gray-green, the back is dark green, the abdomen is bright red. Sharp teeth, jaws developed with spines, known for ferocity. It is difficult to identify males and females. Generally male fish color is more colorful, smaller individual, female fish individual larger, lighter color, sexual maturity when the abdomen is more swollen. Red belly white pomfret this fish body left and right side flat, before and after the oval, tail fin slightly forked, the maximum body length of only about 32 centimeters. Body color varies greatly, the adult fish dorsal side is blue-gray to gray-black, the abdomen has a silver-gray luster. Juvenile fish body side is gray-green, dark green back, throat and chest and abdomen for the vermilion, the appearance is very similar to our country is promoting the breeding of short cover giant fat carp (freshwater pomfret). But the freshwater pomfret has 2 rows of upper and lower jaw teeth, which are flat and wide, and the first row of the lower jaw has only 12-14 teeth, and the second row has 2 teeth; when the mouth is closed, the upper and lower jaw teeth are in parallel contact. Piranhas have only 1 row of upper and lower jaw teeth, which are sharp and triangular, and 28-31 teeth in the lower jaw; when the upper and lower jaws are closed, they are jagged and embedded. Mature piranhas are similar in appearance between males and females, with bright green backs and bright red bellies with markings on the sides of the body. There is a highly developed sense of hearing. Both jaws are short and powerful, with a protruding lower jaw and triangular, sharp teeth that are interlocked above and below each other. It bites down on its prey and then clenches, tearing the flesh off with a twisting motion of the body, and can bite down as much as 16 cubic centimeters of flesh in a single bite. The rotating replacement of teeth allows it to continue feeding, and the powerful array of teeth can cause serious bite wounds. The six-centimeter piranha costs $40 a piece.