A piranha at the Newport Aquarium. Characidae in order Characiformes, freshwater fish that inhabits South American rivers, floodplains, lakes and reservoirs. Although often described as extremely predatory and mainly feeding on fish, their dietary habits vary extensively and they will also take plant material, leading to their the hungry girl diet book pdf as omnivorous. In Venezuela, they are called caribes.
They are known for their sharp teeth and powerful jaws. Piranhas belong to the subfamily Serrasalminae, which includes closely related omnivorous fish such as pacus. Traditionally, only the four genera Pristobrycon, Pygocentrus, Pygopristis, and Serrasalmus are considered to be true piranhas, due to their specialized teeth. However, a recent analysis showed, if the piranha group is to be monophyletic, it should be restricted to Serrasalmus, Pygocentrus, and part of Pristobrycon, or expanded to include these taxa plus Pygopristis, Catoprion, and Pristobrycon striolatus.
Pygopristis was found to be more closely related to Catoprion than the other three piranha genera. The total number of piranha species is unknown and contested, and new species continue to be described.
Estimates range from fewer than 30 to more than 60. Paraná, and the São Francisco River systems, but there are major differences in the species richness. Paraná and 2 in São Francisco. Caño Maporal, a stream in Venezuela.
Aquarium piranhas have been unsuccessfully introduced into parts of the United States. Piranhas have also been discovered in the Kaptai Lake in southeast Bangladesh. Research is being carried out to establish how piranhas have moved to such distant corners of the world from their original habitat.