Naked characin

Naked characin (Gymnocharacinus bergii) is a small species of fish in the family Characidae. It is the southernmost member of the family (together with some Cheirodon species from Chile) and the only member of the genus Gymnocharacinus. It is endemic to a stream near Valcheta in northern Patagonia, Argentina. Adults have no scales. It is endangered because of habitat loss.