Allen's squirrel

Allen's squirrel, Sciurus alleni, is a tree squirrel found only in northern Mexico, where its range covers southeastern Coahuila, central Nuevo León and western Tamaulipas and reaches the far north of San Luis Potosí. No subspecies are recognised. It is yellow-brown overall, grizzled with black and grey, with a darker head, paler sides and legs, a white to buff ring around each eye and a black tail frosted with white; black individuals are sometimes seen. Head and body length is typically 220 to 254 millimetres with a tail of 217 to 247 millimetres, and females tend to be a little heavier than males. The squirrel lives mainly in oak and oak-pine montane forest, but has also been recorded in pecan woods, in pine-cedar and pine-fir-aspen forest, and in similar lowland habitat. Active by day in the canopy and on the ground all year, it builds leaf-and-twig nests in branches or uses tree cavities, and eats mostly tree seeds and fruit along with insects and their larvae. It sometimes raids crops such as maize and peanuts, while logging and forest clearance for farming are its main threats.