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Thousands of fish species — about 2,500 of them named — call the Amazon River home, but scientists estimate nearly half of the marine creatures lurking in the massive stretch of water remain ...

The recent sightings of the Amazon sailfin catfish in Pakistan have sparked concern among environmental experts, who warn ...

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.

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 ...

WASHINGTON, Oct 16 (Reuters) - One of the world's largest freshwater fish is protected by the natural equivalent of a "bullet-proof vest," helping it thrive in the dangerous waters of the Amazon River ...

A study led by the Oswaldo Cruz Foundation (Fiocruz) reveals that fish from all six Amazonian states exceed the acceptable limit for mercury contamination (greater than or equal to 0.5 micrograms per ...