show Abstracthide AbstractThe red or red-bellied piranha (Pygocentrus nattereri) is a species of fish in the subfamily Serrasalminae, which is distributed widely throughout neotropical freshwater rivers of South America, including the Amazon basin, coastal rivers of northeastern Brazil, and the Paraguay and Parana basins. Through media influence, the red piranha has developed a reputation as a ferocious predator, despite being mostly an omnivorous forager, feeding on plants, insects, worms, crustaceans and fish. Only rarely will it exhibit 'feeding frenzy' attacks on large prey. In the wild red piranha exhibit social behavior and swim in schools, usually of 20 to 30 fish.