Piaractus mesopotamicus


Piaractus mesopotamicus, the small-scaled pacu, Paraná River pacu or simply pacu, is a South American ray-finned fish that is native to the Paraguay-Paraná River basin, but it has been introduced by aquaculture activities in a wider area. In its native range it is also known as the pacú chato, pez chato or mbiraí-piraí.
P. mesopotamicus is a robust fish, with ovoid shape, flattened laterally. Its colour is dark grey to silver, with a white belly and a yellow breast. It reaches up to in length and in weight. The other member of its genus, P. brachypomus, can be distinguished by its larger scale-size and the lower number of lateral scales.
P. mesopotamicus is an omnivore. Young individuals usually feed on micro-crustaceans, while adults feed on plant material and insects. Main food items for adults are nuts and seeds that fall from trees in flooded forests. It tolerates water temperatures between, but stops feeding when it falls below.