Dusicyon avus is an extinct species of cerdocyonine canid in the genus Dusicyon, native to South America during the Pleistocene and Holocene epochs. It was medium to large, about the size of a German shepherd. It was closely related to the Falkland Islands wolf or warrah (Dusicyon australis), which descended from a population of D. avus. It appears to have survived until very recently, perhaps 400 years ago.

The Falkland Islands wolf, also known as the warrah and occasionally as the Falkland Islands dog, Falkland Islands fox, warrah fox, or Antarctic wolf, was the only native land mammal of the Falkland Islands. This endemic canid became extinct in 1876, the first known canid to have become extinct in historical times.