New Giant, Air-Breathing Fish Discovered

One of the world's largest, most endangered, and most mysterious freshwater fish has yielded a new surprise: a likely new species—and possibly several more—have been lurking in the backwaters of the Amazon.

New research published by National Geographic explorer Donald J. Stewart and colleagues L. Cynthia Watson and Annette M. Kretzer in the journal Copeia this week reveals strong genetic evidence for an unknown new species of arapaima that was found at several locations in southwestern Guyana.

Long, narrow giants, arapaimas live in tropical South America. They can grow up to 10 feet long and weigh 440 pounds. They breathe air through a primitive lung, and tend to live in oxygen-poor backwatersRead More