White-fronted capuchin can refer to any of a number of species of gracile capuchin monkey which used to be considered as the single species Cebus albifrons. White-fronted capuchins are found in seven different countries in South America: Bolivia, Brazil, Colombia, Venezuela, Ecuador, Peru, and Trinidad and Tobago.
White-fronted capuchins are medium-sized monkeys with a light brown back and a creamy white underside. Like other capuchin monkeys, they are omnivorous, feeding primarily on fruits, invertebrates, other plant parts and sometimes small vertebrates. They are predated upon primarily by raptors and probably small cats, especially the margay, though snakes have been known to attack them. They are polygamous primates and live in fairly large groups of 15 to 35 individuals. Reproductive females give birth to a single young at biennial intervals. They maintain home ranges of and have complex vocal repertoires. They are among the few primates to have been observed crafting and utilising tools in the wild.
White-fronted capuchins are common and widespread, although their population may be declining. The decline is believed to be caused by human-induced habitat loss and degradation, and hunting. In 2008 the International Union for Conservation of Nature (IUCN) classified the Ecuadorian white-fronted capuchin (C. equatorialis) and the Trinidad white-fronted capuchin (formerly regarded as C. albifrons trinitatis) as "critically endangered," and the varied white-fronted capuchin (Cebus versicolor) in Colombia as "endangered." The total population of the Trinidad subspecies was 61 at the last census.
Taxonomy
Even when the white-fronted capuchins were all considered to belong to a single species, there were problems with its name, description and type locality. The holotype does not exist; the original description by Alexander von Humboldt in 1812 describes an animal that is much darker (grayish) than those that exist close to the type locality, and the description includes a dark tail tip, a character that is completely unknown in any population of the species. Additionally, the animal which von Humboldt examined was a tame animal in Maipures, where the species is not found. The closest population is about three kilometers to the north, on the other side of the Tuparro River.
Defler and Hernandez established a phenotype from the population that was called Cebus albifrons albifrons by Hernández C. and Cooper. Another problem has been that the taxon C. a. unicolor described by Spix (1823) and further defined by Hershkovitz was indistinguishable from C. a. albinos; the two are synonymous.
Taxonomic classification Hershkovitz (1949) originally named 13 subspecies, while Hernández-Camacho and Cooper (1976) described eight subspecies for Colombia. Colin Groves assessed the species in 2001, further reducing the number. One notable subspecies outside of Colombia is the critically endangered Trinidad white-fronted capuchin. The following subspecies were recognised by assessors working for the IUCN as of 2015.
Ecuadorian white-fronted capuchin, Cebus albifrons aequatorialis, found in western Ecuador and Peru (critically endangered). White-fronted capuchin, Cebus albifrons albifrons, found in Bolivia, Brazil, Colombia, Peru and Venezuela. Río Cesar white-fronted capuchin, Cebus albifrons cesarae, found in Colombia. Shock-headed capuchin, Cebus albifrons cuscinus, found in Bolivia, Brazil, Ecuador and Peru. Santa Marta white-fronted capuchin, Cebus albifrons malitiosus, found along the northern flanks of the Sierra Nevada de Santa Marta in Colombia. Trinidad white-fronted capuchin, Cebus albifrons trinitatis, 61 individuals estimated on the island of Trinidad in 2008 (critically endangered). Varied white-fronted capuchin, Cebus albifrons versicolor, found in Colombia (endangered).
The IUCN list differs from that by Groves (2005) in that Groves excluded C. a. cesarae and C. a. malitiosus but included C. a. unicolor as a subspecies. In the Handbook of the Mammals of the World (2013) Mittermeier and Rylands limit C. albifrons to gracile capuchins found in the upper Amazon basin in southern Venezuela, southern and eastern Colombia and northwest Brazil, based largely on the work of Jean Boubli, Thomas Defler and Jorge Hernández-Camacho. In particular, the following forms that had previously been considered subspecies or populations of C. albifrons have been reclassified as separate species:
Humboldt's white-fronted capuchin, Cebus albifrons Marañón white-fronted capuchin, Cebus yuracus Shock-headed capuchin, Cebus cuscinus Spix's white-fronted capuchin, Cebus unicolor Sierra de Perijá white-fronted capuchin, Cebus leucocephalus Río Cesar white-fronted capuchin, Cebus cesarae Varied white-fronted capuchin, Cebus versicolor Santa Marta white-fronted capuchin, Cebus malitiosus Ecuadorian white-fronted capuchin, Cebus aequatorialis
Mittermeier and Rylands consider the Trinidad white-fronted capuchin to be synonymous with the brown weeper capuchin (C. brunneus), but other authors including the IUCN regard it as a separate species, C. trinitatis.
The difficulties in identifying separate subspecies and species have been pronounced. Hernández-Camacho and Cooper reported some specimens of capuchin from the Barranquilla animal market had supposedly come from the middle valley of the San Jorge River. It is difficult to determine whether these are white-faced capuchins (Cebus capucinus) or white-fronted capuchins. Intermediate characteristics include a dark crown that is high and removed from the forehead. The white parts on the face are more distinctively bald and the outside parts of the arms and legs are more clear; this suggests they are white-headed capuchin. Some specimens of C. versicolor seen in the market at Magangué‚ and probably captured in the lower Cauca River, show similar tendencies to the above, except that there is no increase in the dark pigmentation. Based on these observations and on various "intermediate" specimens from northern Colombia, it is possible that an investigation of the contact zone between the white-headed capuchin and white-fronted capuchin ultimately could show that these forms are conspecific, or that some species of white-fronted capuchin are actually more closely related to white-faced capuchins than they are to other white-fronted capuchins. Another critical zone for this analysis is an area in northeast Ecuador where C. aecuatoriales and white-faced capuchins are found, although neither sympatric distributions or intergradation have as yet been determined.
Description Male white-fronted capuchins usually weigh an average of and the females an average of , although a male on Mirití-Paraná in Colombia weighed . This primate is usually maroon-white or palomino and creamy white. It has short fingers and an opposable thumb. Like other capuchins its premolars are large, and it has square-shaped molar with a thick enamel to help with cracking nuts. Below are descriptions of the known species for Colombia.
Humboldt's white-fronted capuchin, Cebus albifrons, is found in eastern Vichada, close to the type locality, and was defined by von Humboldt using a tame animal maintained by humans (and a pig) in the village of Maipures. The original description of von Humboldt described an ashy gray animal with a black tail tip, characteristics that are not typical of any known population of white-fronted capuchin. The C. albifrons located three kilometers to the north of Maipures are very light colored animals with yellowish or reddish tones, very similar to the population of Arauca. Spix' white-fronted capuchin, Cebus unicolor is also very light colored with yellowish tones and was once thought to be a likely synonym of C. albifrons. One population of very pallid coloration is found in Arauca, the northern part of Boyacá and the eastern part of Norte de Santander and probably represents C. a. albifrons. The Río Cesar white-fronted capuchin, Cebus cesarae is very light in color and quite well-defined as a subspecies. "The cap is cinnamon or snuff-brown; median dorsal region, forearm and forelag with orangeous and contrasted with sides of back and trunk; hairs of belly and chest ochracous-orange to pale ochraceous-buff and silvery; contrasting pale area of front extending over variable amounts of upper surface of shoulder and inner side of upper arm" (Hershkovitz, 1949). The Santa Marta white-fronted capuchin, Cebus malitiosus, is characterized by a color that is rather dark brown over almost the entire body with yellowish shoulders. "Pale area of front less extensive, upperparts and limbs paler than in hypoleucus. Cap prout's brown, median dorsal region cinnamon brown, forearm and foreleg not markedly contrasting in color with back and sides of body; hairs of belly and chest ochraceous-tawny to cinnamon-brown and silvery; contrasting pale area of front extending well over upper surface of shoulder and inner side of upper arm" (Hershkovitz, 1949). The varied white-fronted capuchin, Cebus versicolor, is a complex which includes dark populations and lighter populations. It includes the former subspecies C. a. pleei. and was once thought to also include the Sierra de Perijá white-fronted capuchin, C. leucocephalus. Herskovitz's description of C. a. pleei is of a very reddish animal, particularly in its limbs while his description of C. a. versicolor is a lighter red. He described C. a. leucocephalus as a dark brown animal with reddish tonalities in the hind legs. Nevertheless, Hernández-Camacho and Cooper discussed evidence that the three subspecies (C. a. leucocephalus, C. a. pleei and C. a. versicolor) could be subsumed into one subspecies (C. a. versicolor), since the variations seem to be found in a very well-defined zone and even in the same groups, close to Barrancabermeja on the eastern bank of the middle Magdalena River in the Department of Santander. This suggested to them that the dark phase (C. a. leucocephalus) and the light phase (C. a. pleei) are extremes of an intermediate (C. a. versicolor). Boubli's research suggested that C. a. pleei may be synonymous with C. versicolor but was more likely synonymous with C. cesarae, which he found to be closely related to C. versicolor. Boubli found C. a. leucocephalus to be a separate species. The shock-headed capuchin, Cebus cuscinus, is found south of the Guamués River and colored a light brown.
Geographic range and habitat White-fronted capuchins are found in a variety of forest types. In Vichada it exploits a more xeric habitat in terms of drainage, compared with the tufted capuchin, which tends to be found in forests that are more mesophytic. It is also found in flooded forests. The white-fronted capuchin survives well in forests growing over white sand and in forests of "high caatinga" growing in the rocks and gravel at the foot of mesas.