A large, reddish form, difficult to distinguish in the field from Microcebus danfossi and Microcebus ravelobensis found north and south of its range, respectively. The head- body length is 9–12.2 cm, the tail length 14.7–17.4 cm, the total length 24.7–29.4 cm, and the body weight about 55 g (E. E. Louis Jr., unpubl. data). The fur is short and dense, being maroon on the dorsum with an orange tinge (sometimes showing a faint dorsal line). The ventrum is creamy white, and the tail is the same color as the body, although the fur changes from short and dense on the proximal part to longer and more sparse at the tip. The color of the head varies between individuals even within a population. In some (possibly young) individuals, the head is uniformly rufous to brown, while others show this color only at a triangularly-shaped part over the eyes, with the crown being pale grayish. The ears are rufous. As with other mouse lemurs, there is a distinct white stripe on the bridge of the nose. The hands and feet are white and poorly-haired (Olivieri et al., 2007a).
This species has not been studied in the wild. It is known to inhabit the primary forests of the Bongolava Mountains (Olivieri et al., 2007a).
Northwestern Madagascar. This species is known only from three small forest fragments in the area around Port-Bergé, between the Mahajamba Est and Sofia rivers, including the type locality Ambodimahabibo (Olivieri et al., 2007a). Prior to its description, the mouse lemur in this region was presumed to be M. ravelobensis.
The most recent IUCN Red List assessment (2008)
classified M. bongolavensis as Data Deficient (DD). It is not
known to occur in any protected area, although it may occur
in the Bongolava Classified Forest. Surveys are needed
to determine the full extent of its range. Consideration should be given to establishing a protected area that includes the Bongolava Classified Forest, the only relatively large forest fragment left that is in its known range.
As of 2010, this species was not being kept in captivity (I. J. Porton, pers. comm.).
At this time, the best place where one can see this species is the type locality at Ambodimahabibo.