Eastern red pandas may be somewhat larger and darker in color than those from western areas.
Red pandas from the eastern sector of the range of the species may be somewhat larger and darker in color than those from western areas, but with considerable variation in both subspecies, and some individuals may be brown or yellowish brown rather than red. Eastern red pandas are distinguished from Western by longer winter coats and greater blackness of the pelage, bigger skulls, more strongly curved foreheads, and more robust teeth.
The red panda is found between 2,200 and 4,800 meters in temperate forests of the Himalayas and high mountains of northern Burma and western Sichuan and Yunnan.
The confirmed western-most range of Ailurus seems to be the Namlung Valley in Mugu District and the Lake Rara region of northwestern Nepal. The southern limit is the Liakiang Range of western Yunnan and the northern and eastern limit is the upper Min Valley of western Sichuan. The existence of Ailurus in southwestern Tibet and northern Arunachal Pradesh is strongly suspected but has not been documented. A specimen exhibited in the Srinagar Museum in Kashmir reportedly was taken in Ladakh, eastern Kashmir; although this could not be confirmed, it would represent a substantial western expansion of the range.
The current distribution of Ailurus suggests a radiation outward from a central core in the Burma-Yunnan-Sichuan highlands along regions of recent orogenic activity, most notably the Himalayas. The zone of highest density includes a region in western China proposed as a Pleistocene refugium for a variety of endemics.