The Amuyao tree-mouse (Musseromys inopinatus)[3] is a species of rodent in the family Muridae.

[1] It is found on Mount Amuyao in Luzon, Philippines.

[1][2] As for all members of the genus Musseromys, they are small murids weighing between 15 and 22 grams.

[2] Two adult specimens were collected, now in the collections of the Field Museum of Natural History (FMNH): Their measurements are as follows : Data on this species endemic to the Philippines is, as of now, known from only one location.

[2] This particularity, alongside a lack of knowledge on the repartition and abundance of the species, brought the IUCN to assess the Amuyao tree-mouse as "Data Deficient".