The Gray-bellied mountain rat, also known as the Gray-bellied limnomys and the Buffy-collared moss-mouse (Limnomys bryophilus), is a species of murid in the family Muridae. It is found only in the Philippines, where it is common at high elevations of the Kitanglad Mountain Range in the province of Bukidnon on the island of Mindanao. Its habitat is the moss-rich montane cloud forest from about 2,250 metres up to about 2,800 metres. The alternative name of "Buffy-collared moss-mouse" reflects the rat's small size.