The collared titi monkey (''Cheracebus torquatus'') is a species of titi, a type of New World monkey. It is

endemic Endemism is the state of a species being found only in a single defined geographic location, such as an island, state, nation, country or other defined zone; organisms that are indigenous to a place are not endemic to it if they are also foun ...

to northern

Brazil Brazil, officially the Federative Republic of Brazil, is the largest country in South America. It is the world's List of countries and dependencies by area, fifth-largest country by area and the List of countries and dependencies by population ...

Taxonomy

At the end of the 1980s, the genus '' Callicebus'' was revised from the Hershkovitz concept of three species to thirteen neotropical species, with the collared titi, ''Callicebus torquatus'', having four subspecies. In 2001, Colin Groves elevated one of the subspecies, the Colombian black-handed titi, ''C. t. medemi'', to ''Callicebus medemi'' and a year later Van Roosmalen ''et al.'' elevated the remaining subspecies to species. These last changes were made with few arguments to support the changes and were apparently influenced by the increasing use of the so-called phylogenetic species concept of Cracraft, which seeks to define species as the "smallest diagnosable cluster of individual organisms within which there is a parental pattern of ancestry and descent." The species complex was updated to ''Cheracebus'' in 2016. The recent discovery of a diploid number of 16 for the black titi, ''Cheracebus lugens'', in Brazil suggested that (with the previously known 2n=20 of another, unidentified population of ''C. torquatus'') there are at least two species in this complex. But whether the Lucifer titi, ''Cheracebus lucifer'', or the Colombian black-handed titi, ''Cheracebus medemi'', were good species from this complex was in doubt. However, a 2020 study prove them to be distinct species from ''C. torquatus''. However, the same study found the Rio Purus titi (''C. purinus''), previously thought to be

, to be conspecific with the collared titi, with the type locality and specimen of ''C. torquatus'' being from populations attributed to ''C. purinus''; thus, ''C. purinus'' was synonymized with ''C. torquatus''. The American Society of Mammalogists,

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 an inventory of the global conservation status and extinction risk of biological ...

, and ITIS follow this synonymization.

Physical description

Five adults weighed an average of 1462 g (range 1410–1722 g) with a head-body length of around 290–390 mm and a tail length of about 350–400 mm. The face has very little hair, being limited to sparse short white hairs over a black skin. There is no sexual dimorphism, although the male has canines a bit longer than the female. The species has the smallest

karyotype A karyotype is the general appearance of the complete set of chromosomes in the cells of a species or in an individual organism, mainly including their sizes, numbers, and shapes. Karyotyping is the process by which a karyotype is discerned by de ...

known for primates, 2n=16 recently described by Bonvicino ''et al.'' The pelage is typically uniformly reddish brown or blackish brown. The tail is blackish mixed with some reddish hairs with hands and feet whitish or dark brown. This pelage contrasts in all of the subspecies with a band of white hair which extends upward from the chest and follows the neck, prolonging itself to the ears. This extension to the ears is weak, different from the other ''Cheracebus'' species which have white extending to the base of the ears.

Geographic distribution and habitat

This species is thought to be restricted to

, although it may range into adjacent

Colombia Colombia, officially the Republic of Colombia, is a country primarily located in South America with Insular region of Colombia, insular regions in North America. The Colombian mainland is bordered by the Caribbean Sea to the north, Venezuel ...

. It is found south to the Tapauá River or potentially the Pauiní River, west to the Apaporis and Vaupés rivers, north to the Uaupés River and Rio Negro, and as far east as the town of Manacapurú. If it ranges into

, it may potentially hybridize with the black titi (''C. lugens'') where their ranges overlap. The collared titi is seen most frequently in well-developed, tall forest with a closed canopy, usually over terra firme, but not exclusively so. The species also enters extensive várzea forest, especially if the forest is tall and well-developed. Such várzea forest contrasts with the habitat needs of the coppery titi, which also uses várzea forest and more commonly so. But the coppery titi survives in low, vine-covered, "poor" forest where the collared titi is rarely found.

Conservation status

The collared titi is not considered to be endangered, but where there are many colonists this primate tends to disappear, due to deforestation. The species is commonly hunted and eaten by

indigenous peoples There is no generally accepted definition of Indigenous peoples, although in the 21st century the focus has been on self-identification, cultural difference from other groups in a state, a special relationship with their traditional territ ...

or used as bait for hunting larger carnivores or for fishing; however, where there is plenty of forest meat the species is found commonly close to indigenous settlements. The species is classified ''Least Concern'' (formerly LR) in the

References

;Books cited * * * *

External links

''Callicebus torquatus'', Collared Titi Monkey
on Digimorph {{Taxonbar, from1=Q221577, from2=Q56121464 collared titi Primates of Brazil Endemic mammals of Brazil collared titi Taxa named by Johann Centurius Hoffmannsegg