Aquarium piranhas have been unsuccessfully introduced into parts of the United States. In many cases, however, reported captures of piranhas are misidentifications of pacu (e.g., red-bellied pacu Piaractus brachypomus is frequently misidentified as red-bellied piranha Pygocentrus nattereri). read more
Piranhas have never had the most darling of reputations. Just look at the 1978 cult film Piranha, in which a pack of piranhas escape a military experiment gone wrong and feast on unsuspecting lake-swimmers. read more