The Falkland Island Fox (Dusicyon australis, formerly named Canis antarcticus), also known as the Warrah and occasionally as the Falkland Island Wolf or Antarctic Wolf, was the only native land mammal of the Falkland Islands. This endemic canid became extinct in 1876 (on West Falkland island), the only known canid to have gone extinct in historical times. The most closely related species to the monotypic genus Dusicyon among southern hemisphere foxes is Pseudalopex griseus, the culpeo or Patagonian fox, which itself has been introduced to the Falkland Islands in modern times. It was known from both West and East Falkland, but it is unknown if the varieties were much differentiated.
The fur of the Falkland Island Fox had a tawny colour. The tip of the tail was white. The diet is unknown. Due to the absence of native rodents on the Falklands, its diet probably consisted of ground-nesting birds such as geese and penguins, grubs and insects, as well as seashore scavenging (Allen 1942). They are sometimes said to have dwelt in burrows.
The first recorded sighting was by Capt. John Strong in 1692. Louis Antoine de Bougainville, who established the first settlement in the Falkland Islands termed it a loup-renard (“fox-wolf”) When Charles Darwin visited the islands in 1833 he named the species Canis antarcticus and described it as common and tame. The settlers regarded the fox as a threat to their sheep and organised poisoning and shooting on a massive scale. The absence of forests led to the speedy success of the extermination campaign. This was facilitated by the animal's tameness, as is common in insular species due to the absence of predators - trappers would lure the animal with a chunk of meat held in one hand, and kill it with a knife or stick held in the other. However, it would defend itself from humans occasionally if it needed to, as Admiral George Grey noted when they landed on West Falkland at Port Edgar (Falkland Islands) on December 17, 1836 - “I landed in the creek and had hardly put a foot on shore, when one of the foxes of the country was chased by Pilot. I ran up as they were fighting and came to the poor dog's assistance who had nearly met his match, and a rifle ball soon settled the business, but the Pilot had received a terrible bite in the leg.”
A live Warrah was taken to London Zoo, England in 1868, but survived only a few years. In 1880, post-extinction, Thomas Huxley classified it as related to the coyote. In 1914, Oldfield Thomas moved it into the genus Dusicyon, with the culpeo and South American foxes.
It has been speculated that the unusual distribution of this animal (the only other canine species native to oceanic islands are the Island Fox of California, and Darwin's Fox of Chile - but these habitats are not as remote as the Falklands) and some details of the skull suggest that it originally arrived with natives visiting the islands and was kept by them as a pet in a semi-domesticated state. If that is true, the progenitor form from mainland South America would have become extinct during the last Ice Age. DNA analysis of museum specimens have proved rather inconclusive as to the exact relationship of this animal, some even suggesting hybridization (during the domestication process) with a relative or progenitor of the coyote; it is not known whether this would have been biologically possible. Another possibility is that, during an Ice Age, a land bridge between Falkland islands and South America enabled its ancestors to traverse the distance. At any rate, the Falkland Island Fox is a biographical mystery.
It is commemorated in the Falkland Islands, by the name of one of West Falkland's rivers, the Warrah, and also on the Falkland fifty pence piece. One of the Falkland Islands' conservation magazines is also titled The Warrah. 
Darwin writing about his 1834 visit to the Falklands in The Voyage of the Beagle has the following to say - The only quadruped native to the islands is a large wolf-like fox (Canis antarcticus), which is common to both East and West Falkland. I have no doubt it is a peculiar species, and confined to this archipelago; because many sealers, Gauchos, and Indians, who have visited these islands, all maintain that no such animal is found in any part of South America. Molina, from a similarity in habits, thought that this was the same with his culpeu but I have seen both, and they are quite distinct. These wolves are well known, from Byron's account of their tameness and curiosity, which the sailors, who ran into the water to avoid them, mistook for fierceness. To this day their manners remain the same. They have been observed to enter a tent, and actually pull some meat from beneath the head of a sleeping seaman. The Gauchos also have frequently in the evening killed them, by holding out a piece of meat in one hand, and in the other a knife ready to stick them. As far as I am aware, there is no other instance in any part of the world, of so small a mass of broken land, distant from a continent, possessing so large an aboriginal quadruped peculiar to itself. Their numbers have rapidly decreased; they are already banished from that half of the island which lies to the eastward of the neck of land between St. Salvador Bay and Berkeley Sound. Within a very few years after these islands shall have become regularly settled, in all probability this fox will be classed with the dodo, as an animal which has perished from the face of the earth.”