The Hamlyn's monkey (''Cercopithecus hamlyni''), also known as the owl-faced monkey, is a species of

Old World monkey Old World monkey is the common English name for a family of primates known taxonomically as the Cercopithecidae (). Twenty-four genera and 138 species are recognized, making it the largest primate family. Old World monkey genera include baboons ...

that inhabits the

bamboo Bamboos are a diverse group of evergreen perennial flowering plants making up the subfamily Bambusoideae of the grass family Poaceae. Giant bamboos are the largest members of the grass family. The origin of the word "bamboo" is uncertain, ...

and primary rainforests of the Congo. This species is exceedingly rare and known only from a few specimens; little is known about it. However these specimens tend to be widely dispersed throughout the eastern part of Congo, from the Epulu River to the

Lukuga River The Lukuga River is a tributary of the Lualaba River in the Democratic Republic of the Congo (DRC) that drains Lake Tanganyika. It is unusual in that its flow varies not just seasonally but also due to longer term climate fluctuations. Location ...

and from the

Congo River The Congo River ( kg, Nzâdi Kôngo, french: Fleuve Congo, pt, Rio Congo), formerly also known as the Zaire River, is the second longest river in Africa, shorter only than the Nile, as well as the second largest river in the world by discharge ...

to the Kabale Forest, with one example in northwestern Rwanda. Geographically it corresponds quite closely to another species of monkey,

L'Hoest's monkey L'Hoest's monkey (''Allochrocebus lhoesti'') or mountain monkey, is a guenon found in the upper eastern Congo basin. They mostly live in mountainous forest areas in small, female-dominated groups. They have a dark coat and can be distinguishe ...

''C. lhoesti''. It travels on the ground, and researchers think that it may be awake primarily by night. Schwarz (1928) grouped this species with ''C. l'hoesti'', while Elliot (1913) noted its distinctive cusp pattern on the third molar, and reassigned it to a separate genus, ''Rhinostigma''. This he believed to be an intermediate between ''Cercopithecus'' and ''Cercocebus''. Hamlyn's monkey has one subspecies other than the nominate. In weight, the male is much larger than the female, with the average adult weighing 7 to 10 kg, while females weigh on average 4.5 to 6 kg.Singapore Zoological Gardens Docents (1999).
Cercopithecids (Cercopithecidae)
''. Retrieved on 10 July 2006. It is thought to be a frugivore-folivore in diet. Some published reports indicated that Hamlyn's Monkey lives in small groups, of ten members or less, with one male and multiple females, with no data to show them occurring in monogamous groups. The species has been found only in higher elevations, above 900m and up to 4600m. In color it is generally dark gray, with a characteristic white stripe which extends from the root of the nose to the upper lip, giving it an owl-like appearance, hence the name "owl-faced monkey". The name "Hamlyn's monkey" and the scientific epithet "''hamlyni''" come from the animal dealer who first brought this species to the London Zoo. It has scent glands on its chest with which it territorial marking, marks its territory. Both sexes have bare, blue buttocks, and the mature male has bright red and blue genitals. The juvenile coloration is a yellow-brown coat and a pink face. In captivity it has been known to live for about 33 years. Like others of this genus, it covers a wide area in its daily travels, mostly in a search for food.

Subspecies

* ''Cercopithecus hamlyni hamlyni'' * ''Cercopithecus hamlyni kahuziensis''

Notes

External links

* ARKive
Images of the owl-faced guenon ''(Cercopithecus hamlyni)''
Guenons, Hamlyn's monkey Mammals of the Democratic Republic of the Congo Mammals of Rwanda Fauna of Central Africa Mammals described in 1907, Hamlyn's monkey Taxa named by R. I. Pocock {{Primate-stub