Pteronura

Pteronura is a genus of otter containing a single living species, the giant otter (Pteronura brasiliensis), the longest member of the weasel family, reaching up to 1.8 meters in length. Unlike most mustelids it is highly social, typically living in family groups of three to eight members built around a dominant breeding pair, and it is unusually vocal and active by day. The giant otter ranges across north-central South America, mainly along the Amazon River and in the Pantanal, with populations persisting discontinuously in Bolivia, Brazil, Colombia, Ecuador, French Guiana, Guyana, Paraguay, Peru, Suriname, and Venezuela, the Guianas now its last stronghold after the loss of as much as eighty percent of its historic range. It has exceptionally dense fur, a wing-like tail, webbed feet, and individually distinctive markings of white or cream fur on the throat and chin, and feeds almost exclusively on fish, particularly characins and catfish, occasionally taking crabs, turtles, and small caimans; hunting for its pelt and continuing habitat degradation have made it endangered since 1999.