Tufted ground squirrel

The tufted ground squirrel, Rheithrosciurus macrotis, also called the groove-toothed squirrel, is a rodent of the family Sciuridae and the only species in its genus. It lives only on the island of Borneo, on lowland primary forest hillsides below about 1,100 metres. The head and body are about 335 to 352 millimetres long with a tail of 299 to 342 millimetres, and it weighs one to two kilograms. Its incisors have seven to ten distinct grooves, and the ears carry large red to dark brown tufts. The tail is remarkable: its volume including the air in the fluff is about 130 percent of the body volume, the largest tail to body ratio known in any mammal. It forages on the forest floor and lower canopy, appears to be active by day, and is known to eat canarium nuts, fruits, seeds and insects. Local Dayak hunters call it the vampire squirrel and say it kills deer, but this has not been observed by scientists. Deforestation has made it vulnerable and it is totally protected in Sarawak.