The taxonomy of Cercopithecus nictitans is contentious. Grubb et al. (2003) list two subspecies, the geographically widespread C. nictitans nictitans and the more restricted C. nictitans martini, but an isolated population of the latter is thought to represent a distinct and possibly threatened subspecies. A recent morphometric analysis (Cardini & Elton, 2008) misclassified Cercopithecus diana within the Cercopithecus mitis species group, which includes Cercopithecus nictitans, Cercopithecus albogularis, and Cercopithecus mitis. The inclusion of Cercopithecus nictitans within the Cercopithecus mitis species group was confirmed by a recent molecular analysis (Tosi et al., 2005), which supports Cercopithecus albogularis as the sister taxon of C. nictitans.
Cercopithecus nictitans is colloquially known as the “cowardly monkey” because of its high frequency and range of alarm calls.
Auditory, olfactory, visual, and tactile senses are complex, as in most primates. Greater spot-nosed monkeys are especially known for their wide range of vocalizations, which vary from deep booms to chirps, depending on context. Males perform loud, low-frequency boom calls to communicate territoriality and as a predator alarm call. Females and subadults often use short chirps to attract the attention of the group. Loud isolation calls are emitted both by infants and members of the group that have become separated from the troop. Olfactory communication includes mutual genital sniffing and muzzle sniffing, both of which are performed by males. Visual signals include staring, which is often accompanied by head-bobbing in order to indicate a threat display among males. Grimacing or yawning with the canines exposed is an expression of tension or a threat display.
Communication Channels: visual ; tactile ; acoustic
Perception Channels: visual ; tactile ; acoustic ; chemical
Greater spot-nosed monkeys are threatened by habitat loss through deforestation and by hunting for meat, especially in the western portion of its range. On the island of Bioko, populations of C. nictitans martini have undergone steep declines, exceeding 50% during the period of 1986 to 2006.
Populations are known to occur in several protected national parks in Equatorial Guinea and Cameroon. They are listed on Appendix II of CITES and on Class B of the African Convention on the Conservation of Nature and Natural Resources.
Cercopithecus nictitans nictitans is currently listed as Least Concern by the IUCN due to its widespread range and relatively slow rate of population decline. Cercopithecus nictitans martini is classified as vulnerable due to restricted habitat range, ongoing habitat loss, and hunting pressure.
US Federal List: no special status
CITES: appendix ii
Greater spot-nosed monkeys, like other guenons, have been reported to feed on agricultural crops.
Negative Impacts: crop pest
Cercopithecus nictitans is hunted and eaten by humans. They may positively impact forest diversity through seed dispersal.
Positive Impacts: food
Like many other frugivorous Old World monkeys, Cercopithecus nictitans likely plays a large role in seed dispersal, as they often ingest fruits and seeds away from the parent site. Cercopithecus nictitans has been reported to live in mixed-species groups with Cercopithecus diana for mutual predator defense and increased foraging opportunities. Humans (Homo sapiens) hunt them for bushmeat, and also to prevent the greater spot-nosed monkeys from destroying their crops. Greater spot-nosed monkeys carry a variety of parasites, including a primate-specific strain of malaria (Plasmodium falciparum).
Ecosystem Impact: disperses seeds
Commensal/Parasitic Species:
Greater spot-nosed monkeys are primarily frugivorous and granivorous. Like most Old World Monkeys, they have cheek pouches in which to store seeds while foraging. They supplement their diets of fruits and seeds with leaves and insects, and occasionally agricultural crops.
Animal Foods: insects
Plant Foods: leaves; seeds, grains, and nuts; fruit; flowers
Primary Diet: herbivore (Frugivore , Granivore )
Cercopithecus nictitans occupies a variety of dense forest habitats in western and central Africa, ranging from Guinea in the west to the Democratic Republic of the Congo in the east. Populations are found in Guinea, Liberia, Ivory Coast, Nigeria, Cameroon, Equatorial Guinea, Gabon, Central African Republic, Congo, and the Democratic Republic of the Congo.
Biogeographic Regions: ethiopian (Native )
Cercopithecus nictitans is found in the moist tropical lowland and montane forests, tropical swamp and mangrove forests, and dense gallery forests of west and central Africa. Activity is mostly confined to the main canopy layer due to their robust size. They descend voluntarily to the ground only rarely.
Habitat Regions: tropical ; terrestrial
Terrestrial Biomes: forest ; rainforest
Wetlands: swamp
Longevity in the wild has not been recorded, but like other Cercopithecus species, greater spot-nosed monkeys probably live for approximately 20 years.
Range lifespan
Status: captivity: 31 (high) years.
Cercopithecus nictitans, also known as white-nosed guenons, greater spot-nosed monkeys, greater white-nosed monkeys, or putty-nosed monkeys, is most easily recognized by a distinctive white spot covering the nose. Their fur is dark, ranging in color from olive to black, and sometimes have a white patch on the breast. They have cheek pouches in which to store food while foraging. Individuals weigh, on average, between 4.2 and 6.6 kilograms, making them one of the largest of the Cercopithecus group. Sexual dimorphism is evident, with males exhibiting a greater length and body mass than females. They are diurnal and, like all guenons, possess trichromatic vision. Greater spot-nosed monkeys are primarily arboreal, but also move through the forest quadrupedally. Grubb et al. (2003) recognized two subspecies, C. nictitans nictitans and C. nictitans martini, based on geographic range. Cercopithecus nictitans nictitans occupies the eastern section of the range, from Cameroon to the Democratic Republic of the Congo. Cercopithecus nictitans martini is thought to represent the western populations of several distinct subspecies, such as one on the island of Bioko.
Range mass: 4.2 to 6.6 kg.
Other Physical Features: endothermic ; heterothermic ; bilateral symmetry
Sexual Dimorphism: male larger
Male Cercopithecus nictitans sound resonating alarm calls to warn the group of predators and enemies. Their dark coloring also acts as camouflage within the dark tree canopy, allowing them to hide from predators, such as leopards, crowned eagles, and humans.
Known Predators:
Anti-predator Adaptations: cryptic
Greater spot-nosed monkeys have a polygynous mating system, in which one resident adult male resides with several adult females and their offspring. The lone male has exclusive breeding access to all of the females. Male tenures of 5 years are common. Females solicit copulation by presenting their estrous swellings to males. During copulation, the females look over their shoulders and pout, with the lower lip pushed forward and down. Greater spot-nosed monkeys exhibit female philopatry, in which males disperse from natal groups upon adolescence and females stay in their natal range.
Mating System: polygynous
Females reach maturity around 4 years of age. Once pregnant, they gestate for 172 days on average. They give birth to one offspring approximately every two years. There is little information available on the reproductive cycle, breeding season, and parental investment of greater spot-nosed monkeys. However, it is assumed that, like other Cercopithecus species, the young are relatively well-developed at birth and that mothers will invest in their own offspring for approximately six months.
Breeding interval: Greater spot-nosed monkeys breed once every two years.
Breeding season: Breeding season is unknown, but it is probably year-round, as in Cercopithecus mitis.
Average number of offspring: 1.
Average gestation period: 172 days.
Average time to independence: 4 years.
Key Reproductive Features: iteroparous ; year-round breeding ; gonochoric/gonochoristic/dioecious (sexes separate); sexual ; fertilization ; viviparous
There is little information regarding the level of parental investment in Cercopithecus nictitans, although females certainly invest heavily in offspring through gestation, lactation, and juvenile protection.
Parental Investment: precocial ; female parental care ; pre-fertilization (Provisioning, Protecting: Female); pre-hatching/birth (Provisioning: Female, Protecting: Female); pre-weaning/fledging (Provisioning: Female, Protecting: Female)
