The Mount Graham red squirrel (Tamiasciurus hudsonicus grahamensis) is an endangered subspecies of the American red squirrel (Tamiasciurus hudsonicus) native to the Pinaleño Mountains of Arizona. It is smaller than most other subspecies of red squirrel, and also does not have the white-fringed tail that is common to the species. Its diet consists mainly of mixed seeds, conifer cones and air-dried fungi. It exhibits similar behavior to other squirrels in its species.