Geographic Range
        L’Hoest’s monkeys (
        
         Cercopithecus lhoesti
        
        ) are found in montane forests of the Albertine Rift, including southwestern Uganda,
            Rwanda, Burundi, and Democratic Republic of the Congo.
        
Habitat
        L'Hoest's monkeys reside in montane tropical rainforests, including both primary and
            secondary forests. In secondary forests, they occupy the thick underbrush that grows
            where trees have fallen. L'Hoest's monkeys can be found at altitudes ranging from
            900 to 2,500 m. The species is typically more terrestrial than other
        
         guenons
        
        .
        
- Habitat Regions
 - tropical
 
- Terrestrial Biomes
 - forest
 - rainforest
 - mountains
 
Physical Description
        L’Hoest’s monkeys are large, strikingly patterned monkeys with long limbs and a long
            tail. Females weigh approximately 3.5 kg, while males weigh approximately 6 kg. They
            are usually 31.7 to 68.6 cm in length, and tail length ranges from 48.3 to 99.1 cm.
            L'Hoest's monkeys are mostly covered in short dark gray fur, and they have a large
            chestnut saddle pattern on their back. There is also a distinctive large, conspicuous
            patch of white fluffy fur from the throat across the sides of the head almost to the
            ears. Their limbs and belly are black. Their face is mostly dark, with paler pinkish-white
            areas around the eyes and nose. Their long tail is medium gray, blacker near the tip,
            and is often held so the tip bends forward. Their eyes are bright orange. In males,
            the scrotum is bright blue in color, but otherwise both sexes are similar in coloration.
            L'Hoest's monkeys have narrow feet which aide running on the ground. They also have
            cheek pouches, used to carry food while foraging.
        
- Other Physical Features
 - endothermic
 - bilateral symmetry
 
- Sexual Dimorphism
 - male larger
 - sexes colored or patterned differently
 - male more colorful
 
Reproduction
        L'Hoest's monkeys are polygynous. A single male lives and mates with many females.
            When males have reached sexual maturity they leave the group. When females are ready
            to mate, they direct their hindquarters toward a male, know as presenting.
        
- Mating System
 - polygynous
 
        Female L’Hoest's monkeys usually give birth every other year at the end of the dry
            season. On average, females L'Hoest's monkeys produce a single offspring after 5 months
            of gestation. Infants are born with their eyes open and fully covered in brown fur.
            Their fur darkens to adult coloration around 2 to 3 months of age. Young L'Hoest's
            monkeys nurse until mothers birth another offspring, but frequency of nursing considerably
            decreases after the first few months. On average, weaning occurs around 1 year of
            age. When males reach sexual maturity, they leave the group.
        
- Key Reproductive Features
 - iteroparous
 - seasonal breeding
 - gonochoric/gonochoristic/dioecious (sexes separate)
 - sexual
 - induced ovulation
 - fertilization
 - viviparous
 
        After birth, a baby L'Hoest's monkey clings to its mother's belly while she licks
            it clean.  Females in the group try to hold new infants. Because social groups are
            composed of related females and young, parental care likely occurs. Young L'Hoest's
            monkeys often entwine their tail with their mother's.
        
- Parental Investment
 - female parental care
 - 
         
          pre-hatching/birth
         
         
- 
           
            provisioning
           
           
- female
 
 - 
           
            protecting
           
           
- female
 
 
 - 
           
            provisioning
           
           
 - 
         
          pre-weaning/fledging
         
         
- 
           
            provisioning
           
           
- female
 
 - 
           
            protecting
           
           
- female
 
 
 - 
           
            provisioning
           
           
 - post-independence association with parents
 
Lifespan/Longevity
        The lifespan of L'Hoest's monkeys in the wild is currently unknown. One captive specimen
            lived to be 24.1 years of age.
        
Behavior
        L’Hoest’s monkeys live in groups with a single male and 10 to 17 females or young,
            most of which are related. They forage and sleep as a group in trees, and also participate
            in mutual grooming, which solidifies close bonds within the group. They rarely associate
            with other
        
         guenons
        
        . L’Hoest’s monkeys are diurnal and are more terrestrial than most other
        
         guenons
        
        . They travel on the ground and, unusual for
        
         primates
        
        , may also flee from predators while on the ground.
        
Home Range
Little information is available regarding the home range of L'Hoest's monkeys.
Communication and Perception
        L'Hoest's monkeys occassionally flee from predators while on the ground, which necessitates
            coordination, though the manner of this coordination is unknown. When females are
            ready to mate, they direct their hindquarters toward a male, know as presenting. L'Hoest's
            monkeys also utilize a variety of behaviors as a threat display. Staring involves
            fixing the eyes on a subject, raising the eyebrows, stretching the facial skin, and
            moving the ears back. Often, they open their mouth but do not display their teeth.
            Additionally, they may engage in head-bobbing, which often occurs with staring with
            an open mouth, and is also a threat display.
        
Food Habits
        The diet of L'Hoest's monkeys consists mainly of fruits, leaves, and invertebrates.
            Invertebrates typically constitute a little less than half of the diet, while fruits
            and plant materials make up over 50%. However, in some locations, the dietary percentage
            of invertebrates is as low as 9%. L’Hoest’s monkeys usually forage for mushrooms,
            terrestrial herbs, and arthropods in the lower strata of the forest and search the
            upper strata for small fruits, buds, flowers, young leaves (which have more protein
            than mature leaves), and herbaceous stems. They often look for arthropods in shallow
            streams, fallen leaves, trunks, and branches of the forests. L'Hoest's monkeys favor
            fruits of
        
         Myrianthus arboreus
        
        ,
        
         Polycias fulva
        
        ,
        
         Musanga leo-errerae
        
        , and
        
         Ficus
        
        spp. Some invertebrates in their diet include
        
         insects
        
        ,
        
         earthworms
        
        ,
        
         spiders
        
        ,
        
         ants
        
        , and
        
         grasshoppers
        
        . L'Hoest's monkeys also have cheek pouches, in which they carry food while foraging.
        
- Animal Foods
 - insects
 - terrestrial non-insect arthropods
 
- Plant Foods
 - leaves
 - wood, bark, or stems
 - fruit
 - flowers
 
- Other Foods
 - fungus
 
Predation
        Predation of L'Hoest's monkeys by
        
         common chimpanzees
        
        has been observed in the Kahuzi forests in the Democratic Republic of Congo. Additionally,
        
         crowned hawk-eagles
        
        prey on
        
         guenons
        
        , including L'Hoest's monkeys. To escape eagles, they flee on the ground, which is
            uncharacteristic of
        
         primates
        
        . L'Hoest's monkeys are also hunted by humans for bushmeat.
        
Ecosystem Roles
        Due to their semi-frugivorous diet, L’Hoest’s monkeys play a role in seed dispersal.
            Members of this species are known to host two types of gastrointestinal worm parasites,
        
         Strongyloides fulleborni
        
        and a species of
        
         Trichurus
        
        .
        
- Ecosystem Impact
 - disperses seeds
 
Economic Importance for Humans: Positive
        L'Hoest's monkeys are hunted for bushmeat.
        
- Positive Impacts
 - food
 
Economic Importance for Humans: Negative
        L'Hoest's monkeys are occasionally infected with Simian Immunodeficiency Virus, or
            SIV. When transmitted to humans, this virus becomes HIV.
        
- Negative Impacts
 - 
         
          injures humans
         
         
- carries human disease
 
 
Conservation Status
        L'Hoest's monkeys are considered vulnerable by the ICUN Red List and endangered by
            the US Federal List. Populations are decreasing because of deforestation due to agricultural
            expansion as well as hunting. L'Hoest's monkeys were at one point listed in Appendix
            II by The Convention on International Trade in Endangered Species (CITES), which means
            international trade of this species is monitored. However, hunting of this species
            for bushmeat still occurs. L'Hoest's monkeys are most vulnerable to snares and shotgun
            hunting.
        
Other Comments
        L'Hoest's monkeys,
        
         Cercopithecus lhoesti
        
        , were formerly classifed as a single speices with two other taxa of western Africa,
            Preuss's Monkey (
        
         Cercopithecus preussi
        
        ) and Sun-tailed Monkey (
        
         Cercopithecus solatus
        
        ).
        
Additional Links
Contributors
Bess Ferguson (author), Michigan State University, Pamela Rasmussen (editor), Michigan State University, Gail McCormick (editor), Animal Diversity Web Staff.
- Ethiopian
 - 
          
living in sub-Saharan Africa (south of 30 degrees north) and Madagascar.
           
- native range
 - 
          
the area in which the animal is naturally found, the region in which it is endemic.
 
- tropical
 - 
          
the region of the earth that surrounds the equator, from 23.5 degrees north to 23.5 degrees south.
 
- forest
 - 
          
forest biomes are dominated by trees, otherwise forest biomes can vary widely in amount of precipitation and seasonality.
 
- rainforest
 - 
          
rainforests, both temperate and tropical, are dominated by trees often forming a closed canopy with little light reaching the ground. Epiphytes and climbing plants are also abundant. Precipitation is typically not limiting, but may be somewhat seasonal.
 
- mountains
 - 
          
This terrestrial biome includes summits of high mountains, either without vegetation or covered by low, tundra-like vegetation.
 
- polygynous
 - 
          
having more than one female as a mate at one time
 
- iteroparous
 - 
          
offspring are produced in more than one group (litters, clutches, etc.) and across multiple seasons (or other periods hospitable to reproduction). Iteroparous animals must, by definition, survive over multiple seasons (or periodic condition changes).
 
- seasonal breeding
 - 
          
breeding is confined to a particular season
 
- sexual
 - 
          
reproduction that includes combining the genetic contribution of two individuals, a male and a female
 
- induced ovulation
 - 
          
ovulation is stimulated by the act of copulation (does not occur spontaneously)
 
- fertilization
 - 
          
union of egg and spermatozoan
 
- viviparous
 - 
          
reproduction in which fertilization and development take place within the female body and the developing embryo derives nourishment from the female.
 
- female parental care
 - 
          
parental care is carried out by females
 
- arboreal
 - 
          
Referring to an animal that lives in trees; tree-climbing.
 
- diurnal
 - 
          
- active during the day, 2. lasting for one day.
 
 
- motile
 - 
          
having the capacity to move from one place to another.
 
- social
 - 
          
associates with others of its species; forms social groups.
 
- visual
 - 
          
uses sight to communicate
 
- tactile
 - 
          
uses touch to communicate
 
- visual
 - 
          
uses sight to communicate
 
- tactile
 - 
          
uses touch to communicate
 
- chemical
 - 
          
uses smells or other chemicals to communicate
 
- food
 - 
          
A substance that provides both nutrients and energy to a living thing.
 
- carnivore
 - 
          
an animal that mainly eats meat
 
- herbivore
 - 
          
An animal that eats mainly plants or parts of plants.
 
- folivore
 - 
          
an animal that mainly eats leaves.
 
- frugivore
 - 
          
an animal that mainly eats fruit
 
- omnivore
 - 
          
an animal that mainly eats all kinds of things, including plants and animals
 
- endothermic
 - 
          
animals that use metabolically generated heat to regulate body temperature independently of ambient temperature. Endothermy is a synapomorphy of the Mammalia, although it may have arisen in a (now extinct) synapsid ancestor; the fossil record does not distinguish these possibilities. Convergent in birds.
 
- bilateral symmetry
 - 
          
having body symmetry such that the animal can be divided in one plane into two mirror-image halves. Animals with bilateral symmetry have dorsal and ventral sides, as well as anterior and posterior ends. Synapomorphy of the Bilateria.
 
References
Basabose, K., J. Yamagiwa. 1997. Predation on mammals by chimpanzees in the montane forest of Kahuzi, Zaire. Primates , 38/1: 45-55.
Beer, B., E. Bailes, G. Dapolito, B. Campbell, R. Goeken, M. Axthelm, P. Markham, J. Bernard, D. Zagury, G. Franchini, P. Sharp, V. Hirsch. 2000. Patterns of genomic sequence diversity among their simian immunodeficiency viruses suggest that L'Hoest Monkeys ( Cercopithecus lhoesti ) are a natural lentivirus reservoir. Journal of Virology , 74: 3892-3898. Accessed February 01, 2009 at http://jvi.asm.org/cgi/content/abstract/74/8/3892 .
Flannery, S. 2007. "L'hoest's Monkey (Cercopithecus lhoesti)" (On-line). The Primata. Accessed February 22, 2011 at L'hoest's Monkey (Cercopithecus lhoesti) .
Gillespie, T., E. Greiner, C. Chapman. 2004. Gastrointestinal parasites of the guenons of western Uganda. Journal of Parasitology , 90/6: 1356-1360.
Hart, J., T. Butynski, J. Hall. 2008. "Cercopithecus lhoesti" (On-line). IUCN Red List of Threatened Species. Accessed February 22, 2011 at http://www.iucnredlist.org/apps/redlist/details/4220/0 .
Kaplin, B. 2001. Ranging behaviors of two species of guenons (Cercopithecus lhoesti and C. mitis doggetti) in the Nyungwe forest reserve, Rwanda. International Journal of Primatology , 22/4: 521-548.
Mitani, J., W. Sanders, J. Lwanga, T. Windfelder. 2001. Predatory behavior of crowned hawk-eagles (Stephanoaetus coronatus) in Kibale National Park, Uganda. Behavioral Ecology and Sociobiology , 49: 187-195.
Santiago, M., F. Bibollet-Ruche, N. Gross-Camp, A. Majewski, M. Masozera, I. Munanura, B. Kaplin, P. Sharp, G. Shaw, B. Hahn. 2003. Noninvasive detection of Simian Immunodeficiency Virus infection in a wild-living L’Hoest’s monkey (Cercopithecus lhoesti). AIDS Research and Human Retroviruses , 19/12: 1163-1166.
Tolo, C., J. Baranga, G. Kagoro-Rugunda. 2008. Dietary selection of L’Hoest’s monkeys in Kalinzu forest reserve, southwestern Uganda. African Journal of Ecology , 46/2: 149-157.
de Magalhaes, J., J. Costa. 2009. A database of vertebrate longevity records and their relation to other life-history traits. Journal of Evolutionary Biology , 22/8: 1770-1774. Accessed February 22, 2011 at http://genomics.senescence.info/species/entry.php?species=Cercopithecus_lhoesti .
2008. "BBC Science & Nature: Animals" (On-line). Accessed September 13, 2008 at http://www.bbc.co.uk/nature/wildfacts/factfiles/664.shtml .
1976. "Endangered Species Program" (On-line). Accessed September 03, 2008 at http://endangered.fws.gov/wildlife.html .
Wildscreen. 2007. "L’Hoest’s monkey (Cercopithecus lhoesti)" (On-line). ARKive Images of Life on Earth. Accessed February 22, 2011 at http://arkive.org/lhoests-monkey/cercopithecus-lhoesti/#text=All .
2005. "Oregon Zoo Animals" (On-line). Accessed September 13, 2008 at http://web.archive.org/web/20060513150520/http://www.oregonzoo.org/Cards/Primates/monkey.lhoest.htm .