R Vasconcellos · CC BY 4.0Pacu
Piaractus mesopotamicus · paku
A round, flat fish with delicious flesh, the vegetarian cousin of the piranha.
What it is
A robust member of the piranha family, oval and flattened, silver with a yellowish chest. Despite its relatives, it is omnivorous and eats plenty of fruit and seeds that drop into the water from riverside trees. It spawns in summer, between December and January, and is one of the most prized river fish on Paraguayan tables.
Did you know…?
By swallowing whole fruit and releasing the seeds downstream, it helps spread the trees of riverside forests.
Where
The Paraguay and Paraná rivers and connected lagoons. It is also farmed in fish ponds in several parts of the country.
Researched and reviewed in September 2026 with 3 sources. A second reviewer checked dates, coordinates and lodging. Hours and prices may change.