Sketch of arctic fox skull.
Date 1988
Source V. G. Heptner, et al. (1988) Mammals of the Soviet Union, vol. 2, part 1a
Author N. N. Kondakov
Source: https://commons.wikimedia.org/wiki/File:MSU_V2P1a_-_Alopex_lagopus_skull.png

The Arctic fox (Vulpes lagopus), also known as the white fox, polar fox, or snow fox, is a small fox native to the Arctic regions of the Northern Hemisphere and common throughout the Arctic tundra biome. It is well adapted to living in cold environments. It has a deep thick fur which is brown in summer and white in winter.