A remarkable new fish, Priocharax rex, has been discovered in Colombia's Amazon. This tiny species, measuring just 0.8 inches ...

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 ...

A newly found tiny Amazon fish features a unique organ between its fins, challenging assumptions about miniaturized aquatic ...

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 ...

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Paleontologists discovered a fossilized skull of a newly described species of giant freshwater dolphin in the Peruvian Amazon, which lived around 16 million years ago and is considered the ...

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 ...

Legend has it that the Santiago river used to swallow the canoe of anyone trying to explore it. Now an indigenous community is discovering surprising species in its waters. We stepped into the wooden ...

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 ...