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Measuring 10 feet (3 meters) long and weighing in at more than 400 pounds (180 kilograms), it's hard to imagine that the arapaima, the largest fish in the Amazon River basin, could ever go missing.

Amazon basin fish species living in lakes, floodplain forests and river systems need a high degree of connectivity to stay genetically diverse and healthy, but this connectivity is threatened by ...

A fish larger than a man, tasty as well as beautiful, the freshwater pirarucu is a favorite with poachers in a lawless part of the Amazon jungle where Brazil, Peru and Colombia meet. Prized for its ...

In the Amazon, Johnny Appleseed may be a fish. When rivers in the Amazon Basin flood into surrounding forests and savannas, a fruit-eating fish called a tambaqui proves itself a champion at excreting ...

A new type of giant Amazonian fish — one for which only a single species was known for more than a century — has been discovered in Brazil, scientists say. The fish is a new species of arapaima, which ...

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 ...

Piranhas are among the most deadly creatures in the water, with razor-sharp teeth capable of slicing flesh easily, but a fish in the Amazon River basin has developed a "bulletproof vest" to protect ...

A freshwater Amazonian fish has evolved scales with microscopic armorlike structures specially designed to resist a piranha's piercing bite, new research shows. Arapaima gigas is the largest — and ...