Uakari (, ) is the common name for the

New World monkey New World monkeys are the five families of primates that are found in the tropical regions of Mexico, Central and South America: Callitrichidae, Cebidae, Aotidae, Pitheciidae, and Atelidae. The five families are ranked together as the Ceboid ...

s of the

genus Genus ( plural genera ) is a taxonomic rank used in the biological classification of living and fossil organisms as well as viruses. In the hierarchy of biological classification, genus comes above species and below family. In binomial n ...

''Cacajao''. Both the English and scientific names are believed to have originated from indigenous languages. The uakaris are unusual among New World monkeys in that the tail length (15–18 cm) is substantially less than their head and body length (40–45 cm). Their bodies are covered with long, loose hair but their heads are bald. They have almost no

subcutaneous fat The subcutaneous tissue (), also called the hypodermis, hypoderm (), subcutis, superficial fascia, is the lowermost layer of the integumentary system in vertebrates. The types of cells found in the layer are fibroblasts, adipose cells, and mac ...

, so their bald faces appear almost skull-like. Like their closest relatives the

saki monkey Sakis, or saki monkeys, are any of several New World monkeys of the genus ''Pithecia''. They are closely related to the bearded sakis of genus ''Chiropotes''. Range Sakis' range includes northern and central South America, extending from the s ...

s, they have projecting lower

incisor Incisors (from Latin ''incidere'', "to cut") are the front teeth present in most mammals. They are located in the premaxilla above and on the mandible below. Humans have a total of eight (two on each side, top and bottom). Opossums have 18, w ...

s. These monkeys have the most striking red facial skin of any primate. Females choose their mates based on how red the male's face is. Evidence suggests that the red facial coloration reflects the health of the primate. The uakari is one of the least known monkeys in

South America South America is a continent entirely in the Western Hemisphere and mostly in the Southern Hemisphere, with a relatively small portion in the Northern Hemisphere at the northern tip of the continent. It can also be described as the souther ...

. The four species of uakari currently recognized are all found in the north-western

Amazon basin The Amazon basin is the part of South America drained by the Amazon River and its tributaries. The Amazon drainage basin covers an area of about , or about 35.5 percent of the South American continent. It is located in the countries of Boli ...

. The

bald uakari The bald uakari (''Cacajao calvus'') or bald-headed uakari is a small New World monkey characterized by a very short tail; bright, crimson face; a bald head; and long coat. The bald uakari is restricted to várzea forests and other wooded habita ...

, remarkable for its brilliant scarlet complexion, is found north of the Amazon River, and south of the

Japurá River The Japurá River or Caquetá River is a river about long in the Amazon basin. It rises in Colombia and flows eastward through Brazil to join the Amazon River. Course The river rises as the Caquetá River in the Andes in southwest Colombia. ...

in the

Mamirauá Sustainable Development Reserve The Mamirauá Sustainable Development Reserve ( pt, Reserva de Desenvolvimento Sustentável Mamirauá) in the Brazilian state of Amazonas, near the city of Tefé, is a reserve near the village of Boca do Mamirauá. It includes mostly Amazonian ...

. The black-headed uakari is found north of the

Amazon Amazon most often refers to: * Amazons, a tribe of female warriors in Greek mythology * Amazon rainforest, a rainforest covering most of the Amazon basin * Amazon River, in South America * Amazon (company), an American multinational technolog ...

and south of the Rio Negro. The Neblina uakari is found north of the Rio Negro, west of the Rio Marauiá and east of the

Casiquiare canal The Casiquiare river () is a distributary of the upper Orinoco flowing southward into the Rio Negro, in Venezuela, South America. As such, it forms a unique natural canal between the Orinoco and Amazon river systems. It is the world's largest r ...

. The Aracá uakari is currently known only from the Rio Curuduri basin. They have been observed both in small groups and in larger troops of up to 100. When traveling through the forest they move in the lower branches of the trees, though when foraging they also go up to the canopy. They mostly eat fruit, and unlike other Neotropical frugivores will consume a large amount of unripe fruit for which they have specialised dentition. They also eat flowers, seeds, invertebrates, buds and leaves. Uakari are found in neotropical

flooded or

riparian A riparian zone or riparian area is the interface between land and a river or stream. Riparian is also the proper nomenclature for one of the terrestrial biomes of the Earth. Plant habitats and communities along the river margins and banks a ...

forests, including

Brazil Brazil ( pt, Brasil; ), officially the Federative Republic of Brazil (Portuguese: ), is the largest country in both South America and Latin America. At and with over 217 million people, Brazil is the world's fifth-largest country by area ...

, Colombia,

Peru , image_flag = Flag of Peru.svg , image_coat = Escudo nacional del Perú.svg , other_symbol = Great Seal of the State , other_symbol_type = Seal (emblem), National seal , national_motto = "Fi ...

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 ...

Species

There are four species in this genus: * Genus ''Cacajao'' **

Bald uakari The bald uakari (''Cacajao calvus'') or bald-headed uakari is a small New World monkey characterized by a very short tail; bright, crimson face; a bald head; and long coat. The bald uakari is restricted to várzea forests and other wooded habita ...

or red uakari, ''C. calvus'' *** ''Cacajao calvus calvus'' *** ''Cacajao calvus ucayalii'' *** ''Cacajao calvus rubicundus'' *** ''Cacajao calvus novaesi'' *Black-headed uakari species group ** Golden-backed or black-headed uakari, ''Cacajao melanocephalus'' ** Aracá uakari, ''Cacajao ayresi''* ** Neblina uakari, ''Cacajao hosomi''* In 2014 Ferrari ''et al.'' proposed an alternative taxonomy for the ''C. melanocephalus'' group which recognizes the Aracá uakari as a subspecies of the golden-backed uakari, and also recognized ''Cacajao ouakary'' as a separate species, whereas current consensus is that ''C. ouakary'' is a junior synonym of ''C. melanocephalus''. This revision is not universally accepted.

References

External links

Primate Info Net ''Cacajao'' Factsheet
* ttp://www.uakari.co.uk The Red Uakari Monkey Project {{Taxonbar, from=Q1048171 Sakis and uakaris Taxa named by René Lesson