This medium-sized lemur has a horizontal posture, which is suited to its predominantly quadrupedal mode of movement. These lemurs are also capable of leaping considerable distances, their long furry tails assisting them in maintaining their balance. Colouration of this lemur differs between the sexes. Males have grey-brown upperparts, paler creamy-grey underparts and a reddish crown. Females have far more reddish-brown upperparts and a grizzled-grey crown. Both sexes have prominent white eyebrow patches and distinctive bushy white cheeks, although these are far less bushy in females than in males. The face, muzzle and mid-forehead are dark grey to black, with a thin dark line dividing the crown.
Red-fronted brown lemurs live in multimale-multifemale groups without a noticeable hierarchy, generally numbering from eight to ten individuals, although group size may range between 4 and 18. In western forests aggregations of between 30 and 100 individuals have even been reported feeding in a single fig tree. Breeding is seasonal with infants generally born in September or October after a gestation period of approximately 120 days. A single offspring is usual, although twins have been reported. Brown lemurs reach sexual maturity between two and three years, and the lifespan in the wild is believed to range between 20 and 25 years. This species is cathemeral, meaning it is active at varying times throughout the day and night. Fruit, mature leaves, flowers, bark, sap, soil, insects, centipedes and millipedes form the bulk of this lemur’s diet.
Found in two distinct populations in the east and west of Madagascar. The eastern and western populations represent two separate subspecies, though these have yet to be officially described. There is also a small introduced population in southern Madagascar at the Berenty Private Reserve.