Rheithrosciurus

Rheithrosciurus is a genus of rodent in the squirrel family Sciuridae containing a single living species, the tufted ground squirrel, found only on the island of Borneo. It forages on the forest floor for nuts, seeds and insects. Its head and body measure roughly 335 to 352 millimeters with a tail of 299 to 342 millimeters and a weight of one to two kilograms, and its incisors carry seven to ten distinctive longitudinal grooves. Its skull is longer and flatter than that of most squirrels, and its coloring is predominantly brown with reddish tones and white to buff stripes along its flanks. The genus is noted for having the largest known tail to body size ratio of any mammal, with tail volume reaching about 130 percent of body volume. Its conservation status is listed as Vulnerable owing to deforestation across its limited range.