There are two different populations of this species in Madagascar, that of the dry forests of the west and that of the humid forests of the east, with different characteristics and behaviors. In the west the lemur population is larger and they extend over a smaller area, while in the east the opposite is true. In the west these animals feed mainly on leaves, while fruits predominate in the diet of populations in the east.

On the other hand, there is sexual dimorphism in this species. In both cases, the muzzle and face are gray to white and a dark line runs across the face from the forehead to the crown of the head. However, the back is more grayish in males and the chest is much more populated; while females have a darker back, from brown to orange.

Like all lemurs, red brown lemur also form social groups. In western populations, one male usually monopolizes the females in the group, while in the east several males can form reproductive pairs.

The red brown lemur is at low risk of threat due to its wide distribution, however its habitat is increasingly being lost due to human settlements and in some cases the animals are victims of hunting.