Endemic to Borneo (Gunung Kinabalu and northern Kalimantan)
The gray-bellied pencil-tailed tree mouse is an arboreal rodent in the family Muridae, endemic to Borneo. It is known from Gunung Kinabalu in Sabah and from Long Petak in northern Kalimantan, and probably has a wider distribution than currently documented. Its natural habitat is montane tropical forest and it is threatened by habitat loss (Wikipedia, general species account).
Description: Wildlife of Malaysia guide, Wildlife of Everywhere (wildlifeofeverywhere.com); general species information paraphrased from Wikipedia (CC BY-SA)
Mammals of the World