Patagonian weasel not been thoroughly studied in the wild, and knowledge of its behavioral patterns is unsure. It reportedly has been kept as a working pet by local ranchers to destroy rodents. Patagonian weasel The Patagonian weasel ("Lyncodon patagonicus") is a small mustelid that is the only member of the genus "Lyncodon". Its geographic range is the Pampas of western Argentina and sections of Chile. An early mention of the animal is in the Journal of Syms Covington, who sailed with Charles Darwin on his epic voyage aboard "HMS Beagle". The Patagonian weasel has a head and body length of , with
Patagonian opossum of La Pampa and Choele Choel (northern Rio Negro Province). It is suggested that the Patagonian opossum may have emerged from the same ancestral group as "Marmosa". They resemble each other closely. In the winter both types have similarly thickening at the base of the tails, where fat accumulates. Yet they do not share all aspects of their lifestyle; Patagonian opossums have a specialized way to gather and consume food, which is made possible by the shortening of their skull and jaws. The shortening occurs in the premolar region; this gives the Patagonian opossum increased biting power. The general appearance