Jentink’s Flying Squirrel Hyloptes platyurus photographed by Shavez Cheema in hill forest near Tawau in Sabah.
Note the distinctive tail shape in the photos below which is broad at the base and tapers towards the tip. There is also a distinctive band of pale fur at the base of the tail.
This squirrel species is common in secondary forest the Malay Peninsular but rare in Borneo with only a few records from hill forest. Most likely it is a different species endemic to Borneo.