Piranhas

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.
Distribution
Piranhas are found in the Amazon basin, in the Orinoco, in rivers of the Guyanas, in the Paraguay-Paraná, and the São Francisco River systems. Some species of piranha have broad geographic ranges, occurring in more than one of the major basins, whereas others appear to have more limited distributions.