The Red Piranha is found in the Paraná-Paraguay and Amazon basins. It can also be found in the rivers of northeastern Brazil and the Guianas.
It is considered one of the most dangerous and aggressive piranha species. Its name comes from the colour of its red belly, which is more intense in males. Contrary to popular belief, red piranhas are not dangerous to humans and, in fact, Amazonian tribes fish by entering the river up to their waists.
It lays its eggs in the sediment, about 5000 of them at a time, in bowl-shaped nests, measuring about 4-5cm deep and 15cm in diameter, built by the males. It congregates in groups of 20-30 individuals and hides in vegetation to catch its prey.
Its main threat comes from commercial trapping.