Perote ground squirrel

The Perote ground squirrel (Xerospermosphilus perotensis) is a species of rodent in the family Sciuridae. It is endemic to Mexico and is currently at risk of extinction. Perote ground squirrels live within the same area as rock squirrels (Otospermophilus variegatus) but they use different microhabitats. In one case it also shares its habitat with the Mexican ground squirrel (Ictidomys mexicanus). Perote ground squirrels have traits similar to those of spotted ground squirrels (X. spilosoma pallescens) found in the northern Mexican Plateau; however they are larger, have shorter tails and yellow backs. Its skull is relatively narrow with a large braincase and they have heavy, thick teeth. Perote ground squirrels have two annual cycles, an active phase (March–November) and a hibernation phase (December–February). Some overlap may occur in March and November however.

X. perotensis was first described as a species in 1893. Much research is being done recently, and many scientists think it should be classified as a subspecies of X. spilosoma. "In either case, and regardless of the position one might adopt around species concepts, it is evident that X. perotensis constitutes an independent and isolated biological entity that has evolved under restricted geographical and ecological contexts as a consequence of recent Pleistocene events".