The gray-handed night monkey (''Aotus griseimembra'') is a species of

night monkey Night monkeys, also known as owl monkeys or douroucoulis (), are nocturnal New World monkeys of the genus ''Aotus'', the only member of the family Aotidae (). The genus comprises eleven species which are found across Panama and much of South Ame ...

formerly considered a subspecies of

Gray-bellied night monkey The gray-bellied night monkey (''Aotus lemurinus''), also called the grey-legged douroucouli Aotidae Night monkeys, also known as owl monkeys or douroucoulis (), are nocturnal New World monkeys of the genus ''Aotus'', the only member of the family Aotidae (). The genus comprises eleven species which are found across Panama and much of South Ame ...

. Its range consists of parts of

Colombia Colombia (, ; ), officially the Republic of Colombia, is a country in South America with insular regions in North America—near Nicaragua's Caribbean coast—as well as in the Pacific Ocean. The Colombian mainland is bordered by the Car ...

and

Venezuela Venezuela (; ), officially the Bolivarian Republic of Venezuela ( es, link=no, República Bolivariana de Venezuela), is a country on the northern coast of South America, consisting of a continental landmass and many islands and islets in th ...

. The exact classification of the gray-handed night monkey is uncertain. While some authors consider it a subspecies of the gray-bellied night monkey, ''A. lemurinus'', other authors consider it a separate species, ''A. griseimembra''. In Colombia, its range consists of the northern portion from the

Sinú River Sinú River (), is a river in northwestern Colombia that flows mostly through the Córdoba Department and into the Caribbean. The river is the third most important river after the Magdalena River and the Cauca River in the Caribbean Region. It i ...

(or perhaps further east) to the Venezuelan border, including the

Sierra Nevada de Santa Marta The Sierra Nevada de Santa Marta (English: ''Snow-Covered Mountain Range of Saint Martha'') is an isolated mountain range in northern Colombia, separate from the Andes range that runs through the north of the country. Reaching an elevation of ...

and the

Magdalena River The Magdalena River ( es, Río Magdalena, ; less commonly ) is the main river of Colombia, flowing northward about through the western half of the country. It takes its name from the biblical figure Mary Magdalene. It is navigable through much of ...

Cauca River The Cauca River () is a river in Colombia that lies between the Occidental and Central cordilleras. From its headwaters in southwestern Colombia near the city of Popayán, it joins the Magdalena River near Magangue in Bolivar Department, and th ...

and Sao Jorge River valleys. In Venezuela, it is found to the west and south of

Maracaibo ) , motto = "''Muy noble y leal''"(English: "Very noble and loyal") , anthem = , image_map = , mapsize = , map_alt = ...

. The gray-handed night monkey is a relatively small monkey, with males weighing approximately and females weighing about . It has short, tight fur. The fur on the back ranges from grayish brown to reddish brown. The belly is yellowish. The hair on the back of the hands and feet is the color of light

coffee Coffee is a drink prepared from roasted coffee beans. Darkly colored, bitter, and slightly acidic, coffee has a stimulant, stimulating effect on humans, primarily due to its caffeine content. It is the most popular hot drink in the world. S ...

with darker hair tips, a key distinguishing feature from other ''A. lemurinus'' subspecies. The gray-handed night monkey is

arboreal Arboreal locomotion is the Animal locomotion, locomotion of animals in trees. In habitats in which trees are present, animals have evolved to move in them. Some animals may scale trees only occasionally, but others are exclusively arboreal. Th ...

and

nocturnal Nocturnality is an animal behavior characterized by being active during the night and sleeping during the day. The common adjective is "nocturnal", versus diurnal meaning the opposite. Nocturnal creatures generally have highly developed sens ...

. It and the other members of the genus '' Aotus'' are the only nocturnal monkeys. Laboratory experiments indicated lower levels of activity even in lighting conditions consistent with a

full moon The full moon is the lunar phase when the Moon appears fully illuminated from Earth's perspective. This occurs when Earth is located between the Sun and the Moon (when the ecliptic coordinate system, ecliptic longitudes of the Sun and Moon opp ...

. It is found in several types of forest, including

secondary forest A secondary forest (or second-growth forest) is a forest or woodland area which has re-grown after a timber harvest or clearing for agriculture, until a long enough period has passed so that the effects of the disturbance are no longer evident. ...

and

plantations, although one study indicated a preference for highly diverse forest. It lives in small groups of between two and six monkeys, most typically two to four, consisting of an adult pair and one infant and several juveniles and/or subadults. Groups are territorial, and groups occupy ranges that overlap only slightly. One study found a population density of 1.5 monkeys per square kilometer, while another found a density of 150 monkeys per square kilometer. The latter figure occurred in a forest remnant that had served as a refuge, which may account for the extremely high density. In common with other night monkeys, the gray-handed night monkey is one of the few

monogamous Monogamy ( ) is a form of Dyad (sociology), dyadic Intimate relationship, relationship in which an individual has only one Significant other, partner during their lifetime. Alternately, only one partner at any one time (Monogamy#Serial monogamy, ...

monkeys. The monogamous pair generally gives birth to a single infant each year, although twins occasionally occur. The

gestation Gestation is the period of development during the carrying of an embryo, and later fetus, inside viviparous animals (the embryo develops within the parent). It is typical for mammals, but also occurs for some non-mammals. Mammals during pregna ...

period is about 133 days. The father carries the infant from the time it is one or two days old, passing it to the mother for

nursing Nursing is a profession within the health care sector focused on the care of individuals, families, and communities so they may attain, maintain, or recover optimal health and quality of life. Nurses may be differentiated from other health ...

. Average interbirth interval for the mother is 271 days. The gray-handed night monkey is listed as "vulnerable" by the

International Union for Conservation of Nature The International Union for Conservation of Nature (IUCN; officially International Union for Conservation of Nature and Natural Resources) is an international organization working in the field of nature conservation and sustainable use of natu ...

(IUCN). It is believed to be particularly threatened in Colombia. This is in part due to habitat loss, but also because many were captured in the 1960s and 1970s for

malaria Malaria is a mosquito-borne infectious disease that affects humans and other animals. Malaria causes symptoms that typically include fever, tiredness, vomiting, and headaches. In severe cases, it can cause jaundice, seizures, coma, or death. S ...

research.

References

{{Taxonbar, from=Q1185106

gray-handed night monkey The gray-handed night monkey (''Aotus griseimembra'') is a species of night monkey formerly considered a subspecies of Gray-bellied night monkey of the family Aotidae. Its range consists of parts of Colombia and Venezuela. The exact classificati ...

Mammals of Colombia Mammals of Venezuela

Taxa named by Daniel Giraud Elliot