Red-bellied piranha

The red-bellied piranha, also known as the red piranha (Pygocentrus nattereri), is a species of freshwater ray-finned fish belonging to the family Serrasalmidae, which includes the pacus, piranhas and related fishes. The red-bellied piranha occurs in South America, found in the Amazon, Paraguay, Paraná and Essequibo basins, as well as coastal rivers of northeastern Brazil. This fish is locally abundant in its freshwater habitat.

They are carnivorous foragers and feed on insects, worms, crustaceans and fish. Opportunistic feeders as they are, will also take advantage of edible aquatic plants as well as any fruits, nuts or seeds that may fall into the waters. They are not a migratory species but do travel to seek out conditions conducive to breeding and spawning during periods of increased rainfall. Red-bellied piranhas often travel in shoals as a predatory defense but rarely exhibit group hunting behavior. Acoustic communication is common and is sometimes exhibited along with aggressive behaviors. They are a popular aquarium fish.