Red-Bellied Piranha (Pygocentrus nattereri)
The red-bellied piranha has a popular reputation as a ferocious predator, despite being primarily scavengers. As their name suggests, red-bellied piranhas have a reddish tinge to the belly when fully grown, although juveniles are a silver color with darker spots. They grow to a maximum length of 13 inches and a weight of 7.7 pounds.
Their diet consists largely of fish, insects, worms, crustaceans, and the occasional larger animal. In contrast to their popular reputation of feeding on live animals, red-bellied piranhas usually feed on dead, dying, and injured vertebrates in the wild, but have been known to attack healthy animals. The fish usually feed in large schools around dusk and dawn. They locate their prey by scent or motion using a set of sensors down the sides of their bodies.
Red-bellied piranha usually spawn around April and May during the rainy season. The male will build a dug-out nest in rocks and vegetation, awaiting a female. Females can lay up to 1000 eggs which the male fertilizes. Males become extremely territorial during spawning, and will prevent other fish from approaching the nest. After the eggs hatch, both parents guard the broods.
Information courtesy of wikipedia.org/wiki/red-bellied_piranha
Photo courtesy of animaladay.blogspot.com