A pair of Eastern Woolly lemurs, (Avahi laniger) nesting during the day. Note the distinctive white stripe along the thigh which is one of the most distinguishing features of the woolly lemurs.
The woolly lemur group of primates contain the only nocturnal members of the family Indridae (which includes the largest living lemur – the Indri). There are presently four recognized species in the woolly lemur group. All of the presently recognized species of woolly lemurs are very similar in appearance and due to their being nocturnal, it can be very difficult to distinguish the differing species in the wild. It can also be difficult to distinguish them from certain species of Lepilemur. There are recorded body sizes for both A. laniger and A. occidentalis (head body lengths of approximately 25 – 30 cm and a tail length of around 31-37 cm). Weight ranges for these two species are approximately 900 and 1,300 grams for A. laniger and 700 to 900 grams for A. occidentalisThere are no reported body size data published for A. unicolor. A single male A. cleesei weighed 830g. The woolly lemurs common name comes from the curly, woolly appearance of the dense fur . Their hindlimbs are proportionally longer than the trunk and forelimbs and they have long tails that are typically longer than the body.
Characteristics of each species
- 'A. laniger'
Darker than A. occidentalis, this species has a dense coat that is grey-brown to reddish, paler towards the tail – which is a rusty red color.
It is reported that there have been no long term studies of A. laniger, but it is thought they may live in monogamous pairs . Groups of up to five have been reported and home range is thought to be around 1-2ha. Where studies have been conducted, all Avahi eat flowers and fruits, but its diet consists mainly of leaves.
A. laniger is considered Least Concern by the IUCN.
- 'A. occidentalis'
It is reported that there have been no long term studies of A. laniger, but it is thought they may live in monogamous pairs . Groups of up to five have been reported and home range is thought to be around 1-2ha. Young leaves and buds are reported to be the preferred food.
'A. occidentalis' is considered Endangered by the IUCN.
- 'A. unicolor'
Back color is sandy-brownish grey. The tail can be slightly darker or even reddish brown although the base of the tail may be cream colored. The coloration of the face gives the impression of a facial mask.
A. unicolor is considered “data deficient” by the IUCN.
- 'A. cleesei'
The fur above the forehead is blackish and forms a dark chevron pattern. The snout is black and hairless. Head body fur is brown-grey. The tail can be grey-brown to grey.
This new species is only known from the Tsingy de Bemaraha region of western Madagascar .
- J. Fleagle (1998). Primate Adaptation and Evolution. Academic Press: New York.
- F. Szalay and E. Delson (2001). Evolutionary History of the Primates. Academic Press, New York.
- Mittermeier et al. (2006). Lemurs of Madagascar. Conservation International.
- J. Fleagle (1998). Distribution and geographic variation in the western woolly lemur (Avahi occidentalis) with description of a new species (A. unicolor). Int. J. Primat., 371-376.