Eulemur rubriventer (I. Geoffroy, 1850)

Eulemur rubriventer is a medium-sized Eulemur with a head-body length of 35–40 cm, a tail length of 43–53 cm, a total length of 78–93 cm, and a weight of 1.6–2.4 kg (Glander et al., 1992; Terranova and Coffman, 1997). This species is sexually dichromatic. In males, the dorsal coat is long, dense, and a deep chestnut-brown. The ventral coat is slightly lighter and more reddish. The tail is darker, shading to black like the muzzle, face and head. Conspicuous patches of white skin form characteristic “tear-drops” beneath the eyes. There is no bushy beard or ear tufts as in other Eulemur species, but the fur around the ears is particularly dense and gives the head a robust appearance. In females, the dorsal coat and tail color are similar to those of the male, but the ventral coat is a highly contrasting creamy-white that may extend all the way to the cheeks. Facial coloration is also similar to that of the male, except that the white patches beneath the eyes are reduced. The head appears less robust, as it lacks the long bushy cheek hairs of the male. Over its relatively large range, the red-bellied lemur is sympatric with four other Eulemur species: E. albifrons in the northern part of its range, E. fulvus toward the middle of its range, and E. rufifrons and E. cinereiceps in the southern part. It can be distinguished from all of them by its dark luxurious coat and the male’s conspicuous white eye patches. Males from the region of Andasibe (= Périnet) appear to have a more distinctive reddish belly compared to populations found farther south, such as in Ranomafana National Park (O. Langrand, pers. obs.).