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A new fish species has emerged, but it does not hail from the realm of Mordor as its name suggests. The relationship between pacus and piranhas has been closely studied by researchers and while the ...

Researchers discovered a new species dwelling at the bottom of a river in the Amazon rainforest, according to a new study. Image from the Journal of Fish Biology A rare new species of fish was ...

A new species of piranha-like fish called pacu was recently found hiding in plain sight among several near-identical species in the Amazon River. Researchers have named it after Sauron from "The Lord ...

The construction of the Balbina hydroelectric dam in the Brazilian Amazon led to the loss of seven endemic fish species in the Uatumã River, researchers have found. The hydroelectric dam has ...

Top-dwelling fish are a great addition to any tank. Not only do they add vibrancy and diversity, but they may be necessary if you keep aggressive bottom-dwellers, like crayfish or crabs. In this guide ...

The pirarucu, the giant fish of the Amazon, was an endangered species. Due to conservation efforts, it's making a comeback. Now a big fish story - seriously. In the Amazon jungle, there is a species ...

One-fifth of fish species in the Mekong river face the threat of extinction, according to a new report from a coalition of regional and international environmental groups. The Mekong -- among the ...