In the wild, C. cephus is not reported to have any adverse effects on humans. However, when kept as pets, their curiosity often leads these monkeys to destruction of property. As mentioned previously, they are also capable of biting.
Predators of C. cephus include leopards, snakes, birds of prey, and humans who occasionally capture these monkeys.
Male moustached guenons produce a distinctive warning tone, which is described as a sharp, staccato, rhythmically repeated bark. A ke-ke-ke call is also used by both sexes, which indicates fear.
Known Predators:
Cercopithecus cephus has a very colorful face, bluish to violet with a bluish-white crescented stripe below the naked nose. Beneath this “moustache” are black hairs along the border of the upper lip and bright yellow bushy whiskers on both sides of the face. The ears are black and the rest of the head is covered with blackish-brown hair. This blackish-brown hair extends dorsally and laterally, with the ventral region having ashy grey hair. The tail, which is longer than the rest of its body, is nonprehensile and is covered in coppery-red hair.
The average length of C. cephus is 520 mm (head to body) and its tail averaging 700 mm. The average mass is about 4 kg. The dental formula is 2/2, 1/1, 2/2, 3/3 = 32.
Females and males are alike in color. Cercopithecus cephus is sexual dimorphic in size with the female being relatively smaller.
Average mass: 4 kg.
Average length: 520 mm.
Other Physical Features: endothermic ; homoiothermic; bilateral symmetry
Sexual Dimorphism: male larger
Average mass: 3585 g.
Little is known about the lifespan of C. cephus in the wild or in captivity. However, one known wild born C. cephus female lived in captivity for 31 years and it is estimated that it was as old as 36 years. Close relatives of moustached guenons have lifespans in the wild averaging 22 years.
Average lifespan
Status: captivity: 36 years.
Average lifespan
Status: wild: 22 years.
Average lifespan
Sex: male
Status: captivity: 23.0 years.
Average lifespan
Sex: female
Status: captivity: 23.0 years.
Cercopithecus cephus inhabits an array of forested regions including primary rainforests, secondary rainforests, and gallery forests.
Habitat Regions: tropical
Terrestrial Biomes: rainforest
Cercopithecus cephus is distributed in western Africa, south and east of the Sanaga River. Its southern and eastern limits are the banks of the Congo/Oubangi river system. However, the region where the Congo River empties into the Atlantic Ocean is no longer a barrier since this species in now found in northwestern Angola and eastern Democratic Republic of the Congo. It is not known when or how C. cephus was able to cross the river barrier at this location, but it is not found much further from this crossing point. Cercopithecus cephus occurs in Equatorial Guinea, Gabon, the Republic of the Congo, southern Cameroon, southwestern Central African Republic, northwestern Angola, and eastern Democratic Republic of the Congo.
Biogeographic Regions: ethiopian (Native )
Cercopithecus cephus is primarily frugivorous. This species has adapted to live on the pulp of oil palm nuts, and as a result, it is only found in regions where there is a constant supply of this fruit. In order to compete effectively with other primate species, C. cephus arrives at a fruiting tree before dawn. Cercopithecus cephus may also feed on fruits in the early evening after other primate species have retreated. In addition to oil palm nuts, moustached guenons consume seeds, leaves, insects, and eggs.
Animal Foods: eggs; insects
Plant Foods: leaves; seeds, grains, and nuts; fruit
Primary Diet: herbivore (Frugivore )
Cercopithecus cephus is accompanied by sneaky and silent birds (Tropicranus albocristatus cassini), which benefit from the insects, numerous seeds, and other vegetable products disturbed by the monkeys. This is commensalism. Because C. cephus is a frugivore, it undoubtedly aids in the dispersal of the seeds of fruit trees.
Ecosystem Impact: disperses seeds
Species Used as Host:
Mutualist Species:
Commensal/Parasitic Species:
Cercopithecus cephus is sometimes kept as a pet. This guenon is usually friendly toward humans and is full of curiosity. However, as is true of all wild animals, C. cephus can bite.
Positive Impacts: pet trade
Cercopithecus cephus is not endangered.
US Federal List: no special status
CITES: no special status
State of Michigan List: no special status
IUCN Red List of Threatened Species: least concern
Cercopithecus cephus uses a trilling call that is soft and oscillates in a descending pitch. These calls are emitted by subadults when approached by an adult, therefore communicating obedience.
Cercopithecus cephus uses staring as a threat display. In this case, a monkey fixes its eyes on another individual with eyebrows raised, scalp retracted, and facial skin stretched by moving the ears back. The color underneath the eyelids contrasts sharply with the adjacent facial color, contributing to the visual effect of this threat. Cercopithecus cephus also stares with its mouth wide open but the teeth covered. This threat expression is usually accompanied by bobbing the head up and down.
Cercopithecus cephus also uses a nose-to-nose greeting, where two monkeys approach each other and touch noses. Such greetings are frequently followed by play or grooming.
Although not documented for this species, many old world primates use some forms of scent-based communication. Cercopithecus cephus may use some chemical communication as well.
Communication Channels: visual ; tactile ; acoustic
Perception Channels: visual ; tactile ; acoustic ; chemical
Cercopithecus cephus is commonly called a moustached guenon or a moustached monkey.
Mating in this species is polygynous, with one male generally mating in a group of 10 to 40 females. A female elicits copulation by directing her rump towards the male, informing him that she is ready for copulation.
In spite of this basic pattern, polygynandrous mating groups sometimes occur. The breakdown of the one-male group structure may lead to between 3 and 6 males attending a group of females on any one day. These males occasionally leave such groups for a few hours to court and mate females in neighboring groups. The presence of several males in the group coincides with elevated levels of sexual activity.
Mating System: polygynous ; polygynandrous (promiscuous)
In the tropics, where there is little annual variation in day length and temperature, annual changes in rainfall and nutrition are most important in determining the reproductive events of C. cephus. In areas of high rainfall, some populations display year round mating and birth. The majority of the C. cephus population has a mating season centered around July, August, and September, with the birth season centered around December, January, and February. Mating and birth seasons usually last three months or less when there is one wet season, and three months or longer when there are two wet seasons each year.
Breeding interval: Females are able to breed yearly.
Breeding season: Breeding takes place from July to September .
Average number of offspring: 1.
Average gestation period: 5.6 months.
Range age at sexual or reproductive maturity (female): 4 to 5 years.
Range age at sexual or reproductive maturity (male): 4 to 5 years.
Key Reproductive Features: iteroparous ; seasonal breeding ; year-round breeding ; gonochoric/gonochoristic/dioecious (sexes separate); sexual ; fertilization ; viviparous
Average birth mass: 340 g.
Average gestation period: 172 days.
Average number of offspring: 1.
Little is documented about the parental investment of C. cephus, but close relatives of moustached guenons produce young that are relatively well developed at birth with open eyes and the means to support their own weight and embrace their mother. Mothers typically care for their young, providing them with food and protection, for a year or longer. Males may be considered to play some role in parental care in that they contribute to the defense of the social group against predators and rival males. This may help to protect the offspring.
Parental Investment: altricial ; pre-fertilization (Provisioning, Protecting: Female); pre-hatching/birth (Provisioning: Female, Protecting: Female); pre-weaning/fledging (Provisioning: Female, Protecting: Male, Female); pre-independence (Protecting: Male, Female); maternal position in the dominance hierarchy affects status of young
The moustached guenon or moustached monkey (Cercopithecus cephus) is a species of primate in the family Cercopithecidae. It is found in Angola, Cameroon, Central African Republic, Republic of the Congo, Democratic Republic of the Congo, Equatorial Guinea, and Gabon.[2]
This monkey is an arboreal, omnivorous, and medium-sized mammal.[4] According to the IUCN, the population of the moustached monkeys is considered to be large;[2] therefore, they are widely used in biological labs.[5][6][7][8][9]
The moustached guenon belongs to the genus Cercopithecus, a genus of Old World monkeys, and in the C. cephus group. It is named by its unique moustached face in the monkeys, which has three recognized subspecies: (1) Red-tailed moustached monkey (C. cephus cephus); (2) Gray-tailed Moustached Monkey (C. cephus cephodes); (3) White-nosed Moustached Monkey (C. cephus ngottoensis).[10][11][12][13][14][15] However, the C. cephus group also includes many other long-tailed monkey that has other unique morphological patterns except the moustache, for example, the regular red-tailed monkeys (Cercopithecus scanius), the red-bellied monkey (C. e. erythrogaster) and the white-throated monkey (Cercopithecus erythrogaster).[12][16] The diversity of the moustached guenon is one of the highest among Cercopithecus species.[17] In addition, it is not the only primate genus with the "moustached" patterns (see also moustached tamarins).
Cercopithecus cephus usually live in undistributed forests, and they are not easy to be recorded by ground-level cameras because they are arboreal.[4][18][19] The C. cephus are diurnal and share vertical spaces with other species. They are born to jump between the tropical trees (up to 20m from a tree to another), and they are widespread in Gabon and Northern Congo.[17] The main region starts from the Sanaga River's South and East side and goes all the way to the Ubangi watersheds, which are mostly covered by the lowland tropical rainforests; however, the gallery forests, flooded forests and mangrove forests are also available for them.[17]
For adults, the average weight of this species is around 4.1 kg for males and 3.6 kg for females.[17][20][21] The average length (head-to-body) is 58 cm for males and 49 cm for females; and the average tail length is 78 cm for males and 69.5 cm for females.[17]
The average life span is around 22 years for the wild guenon and up to 36 in captivity.[17]
The Cercopithecus genus evolved with special visual patterns for higher efficiency in association; therefore, they can have a higher chance of survival. The C. cephus has powerful and enlarged cheekbones, the most common moustache is the crescent white strip of fur under the nose, and the surrounding fur is black, which shows a strong color contrast; hence, the face patterns can be considered as visual signals.[17][22] On the top of the white stripe, the main area of the face is greyish blue, and the eyes are copper. The face pattern doesn't necessarily help to distinguish the male and female guenon. Like other Old World monkeys, the guenon also developed the hairless rump pad for comfortable sitting.[17]
The C. cephus cooperates with the C. nictitans and the C. pogonias ships; for example, the cephus monkeys alert the other two groups when they observe the eagles because they live lower than the other two groups, which will give loud vocal alerts to the cephus monkeys when they feel an aerial danger. Studies have shown that these types of associations did not randomly occur in the evolution process.[23][20] Moreover, the eagle predation mainly shaped these surviving tactics and foraging strategies.[20] The diet of C.cephus includes fruit, insects and leaves, respectively; fruit is the dominant food resource for this species.[20][7] The polyspecific associations are the main reason that these three species can share the same living area.[20] Up to six guenon species can share the same living area, but four guenon species generally share a common area.[22]
Colour patterns in the Cercopithecus provide unique visual identities for each genus which allowed the development of the polyspecific association of the guenon communities. For the red-tailed and the nose-spotted moustached monkeys, the most observable differences are on their faces; however, genital colour contrasts and head movements are some of the less observable differences.[22]
Guenon's foraging efficiency has been shaped significantly by the polyspecific pattern; meanwhile, the quantification of their availability to food remains unsolved due to the complexity of tropical rainforests and the high diversity of food.[20][17]
The antipredator tactics among the three species are also called troop activity, which starts at daybreak and finishes at sunset.[20] The higher interspecific competition was discovered during the troop activity than during the foraging period (fruit feeding time).[20] Nocturnal predators usually come from the ground, making the three species prefer to leave the dense forest at night and sleep in a large tree's crown.[20]
Each troop/group of guenon consists of one alpha male and 10 to 40 females (like a harem); the average size of a troop is 22 members.[17] An outsider male may occasionally come to mate with one of the females; however, there will be a chance to fail and the female will escort him out of the territory.[17]
The C. cephus has surprisingly large cheek pouches which can carry the same amount of food as its stomach, which allows it to store lots of fruits for later eating in a less dangerous area.[17] The regular foraging time fulfills the day time, and the guenon have the habit to sleep with full stomach.[17][22]
Vocal communications, visual identifications, and tactile activities are involved in the troop's daily social activities, and the guenons usually can give loud and continuous sounds and fast movements combined with the readily visual signals.[22][17]
The moustached monkey's vocal performance is similar to that of C. ascanius and C. erythrotis, and hybridization exists among the three species.[12][5] Therefore, Thomas Struhsaker suggests categorizing these three species as one species.[24] However, hybridization also increases the risk of guenon's adaptive advantages, that they might lose their visual patterns during the hybridization.[22][5][7] The hybridization rate remains low between the moustached monkeys and other guenon subspecies due to the guenon's unique face pattern.[25][26]
The guenons usually mate between 4 and 5 years old, with a female showing her rump to the male. The regular time for new births comes at the end of the rainy period of the year due to the subsequent rich food season. If the rainy season is year-round in the equatorial area, the mating and birth seasons can also appear at any time in the year.[17][27]
C. cephus can be fatally overwhelmed by the poliomyelitis virus (e.g., Hartford and SK strains) and can easily generate cross-contamination with other species, such as the Rhesus macaque (Macaca mulatta).[21] The susceptibility of C. cephus to getting infected by poliomyelitis is similar to that of the green monkey (Cercopithecus sabaeus) and the Rhesus macaque.[21]
The study of the X-DNA, Y-DNA, and mtDNA genetic systems of the Cercopithecus monkey hybrid has shown the polyphyletic C. cephus lineages; and the split of the West African species from the Central African ecosystem.[8] Within the genus, C. diana, C. neglectus, C. mona, C. hamlyni, C. nictitans, and C. cephus consist of six special chromosome fissions, which may lead them to a monophyletic clade.[8][28] The biogeographic break in the watershed in Nigeria and Cameroon may involve a three-clade substructure, which is a break that occurred after the Pleistocene glaciation.[8] However, what triggers the polyphyly remains unknown; itcould be inherited from ancestral hybridization or due to incomplete lineage sorting.[8]
On the east side of Gabon, researchers have captured mammals like bats, C. cephus, and Mandrillus sphinx to study the infection rate of the malaria parasites in the genus Hepatocystis.[9] The research involves introducing infected bats to a population of uninfected C. cephus monkeys. The infected bats would eat the monkey's left-over banana skins, which also allowed the two species to be vectored by the mosquitos in the same area. The blood from four C. cephus monkeys were then examined, showing that three of them were infected by the Hepatocystis parasites, indicating possible cross-contamination between C. cephus and the bats.[9][29][30]
Serological screening or surveys are widely used in determining the prevalence of a disease among a certain populations.[6][31] The survey can collect samples from animal's blood or feces.[6] The ebola virus outbreaks were identified as the consequences of independent zoonotic transmission, which makes the outbreaks less predictable.[32][6] The serological survey deployed a specific Luminex-based assay to detect the Immunoglobulin G antibody in different non-human primates (NHPs); and the result has shown only one C. cephus has produced antibodies to the Sudan ebolavirus (SUDV), which means the C. cephus group and all the tested Cercopithecus groups can be considered as intermediate hosts for Ebola virus.[6][32] Consequently, the cross-species transmission can be rocketed in the bushmeat and pet trading markets.
SIVmus is the simian immunodeficiency virus (the monkey version HIV), and it can affect C. cephus easily.[31][33][6] The full-length sequence phylogenetic analysis and the partial pol sequence study have allowed researchers to categorize five new SIVmus strains that can infect C. cephus.[33] Avelin Aghokeng and his colleagues identified the two distinct SIVmus lineages (SIVmus-1 & SIVmus-2) infecting C. cephus isolated in the animals living in the same area. The researchers have studied Peeters et al.'s (2002) data, which collected blood samples from 788 monkeys in Cameroon; 302 monkeys were from the guenons.[33][31] The 788 monkeys were caught for pet and bushmeat trading; 55 adults and 160 infants were sold as pets and 480 adults and 93 infants were sold as bushmeat.[31] Further study of the lineages have shown the existence of CST and recombination including both the categorized and undiscovered SIVmus.[33] As a result, the lentivirus in sympatric NHP species evolved and survived through CST and recombination.[33] The study of SIVmus has shown the virus's strength of survivorship and the risk of infecting human through the bushmeat trading market.[33][31]
The moustached monkeys are the main target in the primate poaching activities and the main victim in the western Africa bushmeat market.[33][31][34][35]
Many C. cephus infants have been captured and sold to people as pets.[31]
Road construction has fragmented the undisturbed areas in Western Africa, which threatens the Cercopithecus living conditions in general because many of them are sympatric.[35][34]
On the other hand, the Road-effect zones (REZs) were rarely calculated for the areas where the primates are usually present in Western Africa.[35][34] Moreover, studies have shown that the distribution of roads can significantly affect primate living areas and population size; for example, the newly built road may facilitate poaching activities in terms of transportation and access to more undisturbed areas.[35][34]
Environmental Impact Assessment (EIA) evaluates the potential impacts from the proposed projects, within which the impact assessors will read and evaluate the quality of the project proposals and send the assessment report to the decision-makers; however, the science was poorly used in EIA.[34][36][37][38] Road construction is one type of projects that needs to go through the EIA procedures.[35] Unfortunately the rocketed infrastructure implementation in Western Africa come with a large scale of deregulations, which indicate low EIA credibility in the related road constructions, which means the REZs may not be considered at all in most areas.[39][34][35] The lack of concern of the road effects to primates have not only push the endangered primates into a more challenging situation, but also make the less concerned primate like the C. cephus more vulnerable as well.[35][34] The C. cephus population resilience to habitat fragmentation due to road construction remains unstudied, and the poaching of the C. cephus has not shown a turning point yet.[34][31] As a result, large population decrease may appear among the geunon's groups. On the other hand, the bushmeat market is highly risky in spreading the discussed zoonoses; and may be even riskier due to the rapid road construction in West Africa.[35][34]
The moustached guenon or moustached monkey (Cercopithecus cephus) is a species of primate in the family Cercopithecidae. It is found in Angola, Cameroon, Central African Republic, Republic of the Congo, Democratic Republic of the Congo, Equatorial Guinea, and Gabon.
This monkey is an arboreal, omnivorous, and medium-sized mammal. According to the IUCN, the population of the moustached monkeys is considered to be large; therefore, they are widely used in biological labs.
