Rylands' bald-faced saki (''Pithecia rylandsi'') is a disputed species of

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 ...

, a type of

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 ...

. It is found in

Bolivia , image_flag = Bandera de Bolivia (Estado).svg , flag_alt = Horizontal tricolor (red, yellow, and green from top to bottom) with the coat of arms of Bolivia in the center , flag_alt2 = 7 × 7 square p ...

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

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 ...

Taxonomy

Populations in this species were formerly classified within the

Rio Tapajós saki The Rio Tapajós saki or Gray's bald-faced saki (''Pithecia irrorata'') is a species of saki monkey, a type of New World monkey, from South America. It is found in parts of western Brazil, southeastern Colombia, southeastern Peru and possibly no ...

(''P. irrorata''), but a 2014 study described these populations as a distinct species, ''P. rylandsi'', based on their distinctive

pelage Fur is a thick growth of hair that covers the skin of mammals. It consists of a combination of oily guard hair on top and thick underfur beneath. The guard hair keeps moisture from reaching the skin; the underfur acts as an insulating blanket t ...

. However, a 2019 study, also analyzing pelage color variation across the range of the ''P. irrorata''

species complex In biology, a species complex is a group of closely related organisms that are so similar in appearance and other features that the boundaries between them are often unclear. The taxa in the complex may be able to hybridize readily with each oth ...

, delineated only two distinctive groups corresponding to ''P. irrorata'' and

Vanzolini's bald-faced saki Vanzolini's bald-faced saki (''Pithecia vanzolinii'') is a species of saki monkey, a type of New World monkey. Its range is in western Brazil. The monkey is named after Brazilian zoologist Paulo Vanzolini. This species was originally described by ...

(''P. vanzolini''), with the distinctive pelage used to distinguish ''P. rylandsi'' falling within the range of variation of ''P. irrorata''. In addition, the study found that due to an unclear

type locality Type locality may refer to: * Type locality (biology) * Type locality (geology) See also * Local (disambiguation) * Locality (disambiguation) {{disambiguation ...

, the holotype of ''P. irrorata'' may have been collected within the range of ''P. rylandsi'', which would render ''rylandsi'' instantly synonymous with ''P. irrorata''. Based on this study, the

American Society of Mammalogists The American Society of Mammalogists (ASM) was founded in 1919. Its primary purpose is to encourage the study of mammals, and professions studying them. There are over 4,500 members of this society, and they are primarily professional scientists ...

(tentatively, pending further phylogenetic studies) synonymized ''rylandsi'' with ''irrorata'', but the

IUCN Red List The International Union for Conservation of Nature (IUCN) Red List of Threatened Species, also known as the IUCN Red List or Red Data Book, founded in 1964, is the world's most comprehensive inventory of the global conservation status of biol ...

and

ITIS The Integrated Taxonomic Information System (ITIS) is an American partnership of federal agencies designed to provide consistent and reliable information on the taxonomy of biological species. ITIS was originally formed in 1996 as an interagenc ...

retain ''rylandsi'' as a distinct species. This species is named after Brazilian primatologist

Anthony Rylands Anthony or Antony is a masculine given name, derived from the '' Antonii'', a ''gens'' ( Roman family name) to which Mark Antony (''Marcus Antonius'') belonged. According to Plutarch, the Antonii gens were Heracleidae, being descendants of Anton ...

, a senior research scientist at

Conservation International Conservation International (CI) is an American nonprofit environmental organization headquartered in Crystal City, Arlington, Virginia. CI's work focuses on science, policy and partnership with businesses, governments and communities. The or ...

, deputy chair of the IUCN/SSC Primate Specialist Group, member of the

Brazilian Academy of Sciences The Brazilian Academy of Sciences ( pt, italic=yes, Academia Brasileira de Ciências or ''ABC'') is the national academy of Brazil. It is headquartered in the city of Rio de Janeiro and was founded on May 3, 1916. Publications It publishes a lar ...

, a former Vertebrate Zoology professor at the

Federal University of Minas Gerais The Federal University of Minas Gerais ( pt, Universidade Federal de Minas Gerais, UFMG) is a federalIn the Brazilian Higher Education context, ''Federal'' does not mean ''collegiate'' (even though most Federal Universities in Brazil enjoy a sim ...

, and founding editor for the journal ''Neotropical Primates''.

Distribution

This species is found in northwestern

, southeastern

, and southern

Rondônia Rondônia () is one of the 26 states of Brazil, located in the northern subdivision of the country (central-western part). To the west is a short border with the state of Acre, to the north is the state of Amazonas, in the east is Mato Grosso ...

& western

Mato Grosso Mato Grosso ( – lit. "Thick Bush") is one of the states of Brazil, the third largest by area, located in the Central-West region. The state has 1.66% of the Brazilian population and is responsible for 1.9% of the Brazilian GDP. Neighborin ...

. It is found north of the

Madre de Dios River The Madre de Dios River () is a river shared by Bolivia and Peru which is homonymous to the Peruvian region it runs through. On Bolivian territory it receives the Beni River, close to the town of Riberalta, which later joins with the Mamore River ...

in Bolivia and Peru, and east & north of the

Guaporé River Guaporé River ( pt, Rio Guaporé, es, Río Iténez) is a river in western Brazil and northeastern Bolivia. It is long; of the river forms the border between Brazil and Bolivia. The Guaporé River is part of the Madeira River basin, which even ...

in Brazil. It may range as far north as the

Ji-Paraná River The Ji-Paraná River (Machado River), sometimes spelled Jiparaná, is a river in Rondônia state in western Brazil. It is a tributary of the Madeira River in the Amazon Basin. For much of its length it runs roughly parallel with the northeastern ...

or west to the

Jamari River The Jamari River is a river of Rondônia state in western Brazil. Part of the river's watershed is covered by the Jacundá National Forest, a sustainable use conservation unit. The Jamari river is dammed by the Samuel Hydroelectric Dam near Po ...

Description

It is one of the largest of the

sakis Sakis is a Greek male given name, a diminutive form of names where the last consonant (consonant preceding the final "S" common in the majority of Greek masculine nouns) is "S", most commonly Athanasius or Anastasius, with the addition of the "aki ...

. This species is easily distinguishable from all other sakis by its very large size, very black, bare face, and the extreme white grizzling, which can often cause older males to look almost entirely white. Younger males are black in color with moderate grizzling. Adult females are almost as intensely white as males, and their hair on the forehead can form white "

bangs Bang or bangs may refer to: Products * M1922 Bang rifle, a US semi-automatic rifle designed by Søren Hansen Bang * Bang, a model car brand * Bang (beverage), an energy drink Geography * Bang, Lorestan, a village in Iran * Bangs, Ohio, Unite ...

Status

This species is thought to be threatened by

deforestation Deforestation or forest clearance is the removal of a forest or stand of trees from land that is then land conversion, converted to non-forest use. Deforestation can involve conversion of forest land to farms, ranches, or urban area, urban ...

for

cattle ranching A ranch (from es, rancho/Mexican Spanish) is an area of land, including various structures, given primarily to ranching, the practice of raising grazing livestock such as cattle and sheep. It is a subtype of a farm. These terms are most often ...

, as well as

poaching Poaching has been defined as the illegal hunting or capturing of wild animals, usually associated with land use rights. Poaching was once performed by impoverished peasants for subsistence purposes and to supplement meager diets. It was set ag ...

, and thus its population is thought to be declining. They are sometimes also found in the

pet trade Wildlife trade refers to the of products that are derived from non-domesticated animals or plants usually extracted from their natural environment or raised under controlled conditions. It can involve the trade of living or dead individuals, ti ...

. It is thus classified as

Vulnerable Vulnerable may refer to: General * Vulnerability * Vulnerability (computing) * Vulnerable adult * Vulnerable species Music Albums * ''Vulnerable'' (Marvin Gaye album), 1997 * ''Vulnerable'' (Tricky album), 2003 * ''Vulnerable'' (The Used album) ...

by the

References

{{Taxonbar, from=Q21306286

Rylands' bald-faced saki Rylands' bald-faced saki (''Pithecia rylandsi'') is a disputed species of saki monkey, a type of New World monkey. It is found in Bolivia, Peru, and Brazil. Taxonomy Populations in this species were formerly classified within the Rio Tapajós ...

Mammals of Brazil Mammals of Bolivia Mammals of Peru

Controversial mammal taxa