GUIRIVULU
South American Folklore
This is the name of a monster in the legends and folklore of South America, especially Chile. The GUIRIVULU is described as a beast that has the shape of a Puma with the head resembling that of a fox. It has the curiously adapted tail that ends in a massive claw. Because of it features it is sometimes called the fox-snake. This monster inhabits the deepest pools and waters of the rivers, where it will attack not only animals but any human that is foolish enough to go near it. Should it come upon a vicim, they are quickly enveloped in the enormous mouth and swallowed into the body, which expands and extends like that of a snake, to take the victim whole.
Source: Giants, Monsters, and Dragons: An Encyclopedia of Folklore, Legend, and Myth