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SAO RAIMUNDO, Brazil - Even in the most biodiverse rainforest of the world, the pirarucu stands out: It can weigh up to 440 pounds, by far the largest of 2,300 known fish species in the Amazon. Not so ...

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 ...

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 ...

MAMIRAUÁ RESERVE, Brazil — On this stretch of the Amazon River, you don't need a fish finder to locate the pirarucu, one of the world's largest freshwater fish. The splashing gives them away. Like the ...

CARAUARI, Brazil (AP) — Even in the most biodiverse rainforest of the world, the pirarucu, also known as arapaima, stands out. First, there is its mammoth size: It can weigh up to 200 kilos (440 ...