how large is the typical piranha
Jawbone of Pygocentrus nattereri. Piranhas are normally about 14 to 26 cm (5.5 to 10.2 in) long, although some specimens have been reported to be up to 43 cm (17 in) in length. Serrasalmus, Pristobrycon, Pygocentrus, and Pygopristis are most easily recognized by their unique dentition.