Arctic fox sleeping in snow

The arctic fox (Vulpes lagopus, formerly known as Alopex lagopus), also known as the white fox, polar fox or snow fox, is a small foxnative to Arctic regions of the Northern Hemisphere and is common throughout the Arctic tundra biome. The Greek word alopex, (ἀλώπηξ) means a fox and Vulpes is the Latin version. Lagopus is derived from Ancient Greek lago (λαγως), meaning "hare", + pous (πους), "foot" and refers to the hair on its feet. Although it has previously been assigned to its own genus Alopex, genetic evidence places it in Vulpes(Mammal Species of the World) with the majority of the other foxes.

The arctic fox lives in some of the most frigid extremes on the planet. Among its adaptations for cold survival are its deep, thick fur, a system of countercurrent heat exchange in the circulation of paws to retain core temperature, and a good supply of body fat. The fox has a low surface area to volume ratio, as evidenced by its generally rounded body shape, short muzzle and legs, and short, thick ears. Since less of its surface area is exposed to the arctic cold, less heat escapes the body. Its furry paws allow it to walk on ice in search of food. The arctic fox has such keen hearing that it can precisely locate the position of prey under the snow. When it finds prey, it pounces and punches through the snow to catch its victim. Its fur changes colour with the seasons: in the winter it is white to blend in with snow, while in the summer months it changes to brown.

Vulpes lagopus (arctic fox) sleeping with its tail wrapped as a blanket.