The Sumatran mountain squirrel (''Sundasciurus altitudinis'') is a species of

rodent Rodents (from Latin , 'to gnaw') are mammals of the Order (biology), order Rodentia ( ), which are characterized by a single pair of continuously growing incisors in each of the upper and Mandible, lower jaws. About 40% of all mammal specie ...

in the family

Sciuridae Squirrels are members of the family Sciuridae (), a family that includes small or medium-sized rodents. The squirrel family includes tree squirrels, ground squirrels (including chipmunks and prairie dogs, among others), and flying squirrel ...

. Its skull reaches sizes between , overlapping with that of the

Palawan montane squirrel The Palawan montane squirrel (''Sundasciurus rabori'') is a species of rodent in the family Sciuridae. It is endemic to the Philippines. Its natural habitat is subtropical or tropical dry forest A forest is an ecosystem characterized by ...

. It was originally described as a

subspecies In Taxonomy (biology), biological classification, subspecies (: subspecies) is a rank below species, used for populations that live in different areas and vary in size, shape, or other physical characteristics (Morphology (biology), morpholog ...

of ''

Sundasciurus tenuis The slender squirrel (''Sundasciurus tenuis'') is a species of rodent in the family Sciuridae. It is arboreal and found in Indonesia, Singapore, Malaysia, and Thailand Thailand, officially the Kingdom of Thailand and historically known a ...

''.

References

Sundasciurus Fauna of Sumatra Rodents of the Philippines Taxa named by C. Boden Kloss Taxa named by Herbert C. Robinson Mammals described in 1916 {{Squirrel-stub