This gibbon is active in trees by day and feeds mainly on fruit. Males have pale cheek fur, and the species occurs in southwestern Kalimantan.
Its coat ranges from light to dark brown. Males, including immature males, have white to cream fur on the cheeks.
It is active in trees by day and eats mainly fruit, as well as young leaves and insects.
A five-year study in Gunung Palung National Park, West Kalimantan, found that fruit and figs made up 70% of 145 independent feeding observations. A separate study tracked four wild groups in Sebangau's mixed-swamp forest, within Central Kalimantan's peat-swamp forest, from 2010 to 2018.
In the adult male type whose colors were described in detail in 1911, a pale forehead band widened into long cheek whiskers and a whitish throat patch; the lower back was paler cream-buff than the upper back.
An extinction-risk assessment has not been added yet.