Howler monkeys are the most widespread primate genus in the Neotropics and are among the largest of the platyrrhines along with the muriquis (Brachyteles), the spider monkeys (Ateles) and woolly monkeys (Lagotrix). The monkeys are native to South and Central American forests. They are famous for their loud howls, which can be heard up to three miles away through dense rain forest. Fifteen species are recognized. Previously classified in the family Cebidae, they are now placed in the family Atelidae. They are primarily folivores but also significant frugivores, acting as seed dispersal agents through their digestive system and their locomotion. Threats include human predation, habitat destruction, illegal wildlife trade, and capture for pets or zoo animals.
The Atelidae are one of the five families of New World monkeys now recognised. It was formerly included in the family Cebidae. Atelids are generally larger monkeys; the family includes the howler, spider, woolly, and woolly spider monkeys. They are found throughout the forested regions of Central and South America, from Mexico to northern Argentina.
The brown howler, also known as brown howler monkey, is a species of howler monkey, a type of New World monkey that lives in forests in southeastern Brazil and far northeastern Argentina (Misiones). It lives in groups of two to 11 individuals. Despite the name "brown howler", it is notably variable in colour, with some individuals appearing largely reddish-orange or black.
The black howler or black-and-gold howler, is among the largest New World monkeys and a member of the Alouatta genus. The black howler is distributed in areas of South America such as Paraguay, southern Brazil, eastern Bolivia, northern Argentina, and Uruguay. This species is sexually dimorphic, with adult males having entirely black fur and adult females and babies of both sexes having an overall golden colouring; which emphasizes black-and-gold in the name. The IUCN Red List has classed the black howler as Near Threatened as a result of a recent population reduction due to a variety of human-caused factors.
The red-handed howler is a vulnerable species of howler monkey, a type of New World monkey. It is endemic to Brazil, found in the southeastern Amazon and disjunctly in the Atlantic Forest between Rio Grande do Norte and Sergipe.
The white-bellied spider monkey, also known as the white-fronted or long-haired spider monkey, is an endangered species of spider monkey, a type of New World monkey. It is found in the north-western Amazon in Colombia, Ecuador, Venezuela, Peru and Brazil, ranging as far south as the lower Ucayali River and as far east as the Branco River. In the past, the Peruvian, brown and white-cheeked spider monkeys have been treated as subspecies of A. belzebuth. As presently defined, the white-bellied spider monkey is monotypic. It has a whitish belly and a pale patch on the forehead, which, despite its common name, often is orange-buff, though this might be due to dirt and other stainers. They live in groups of 20 to 40 individuals, splitting into small parties of 1 to 9 when in activity.
The Peruvian spider monkey, also known as the black-faced black spider monkey, is a species of spider monkey that lives in Peru, as well as in Brazil and in Bolivia. At 60 centimetres long, they are relatively large among species of monkey, and their strong, prehensile tails can be up to 1 m (3 ft) long. Unlike many species of monkey, they have only a vestigial thumb, an adaptation which enables them to travel using brachiation. Peruvian spider monkeys live in groups of 20–30 individuals, but these groups are rarely all together simultaneously. The size and dynamics of the resulting subgroups vary with food availability and sociobehavioral activity. They prefer to eat fleshy fruit, but will change their diet in response to scarcity of ripe fruit. Individuals of this species also eat small animals, insects and leaves based on availability. Females separate from the band to give birth, typically in the fall. These females inhabit a group of core areas where resources are abundant in certain seasons. Typically, males exhibit ranging over longer distances than females, with movement of individuals enhancing the fluidity of subgroup size. Peruvian spider monkey are independent at about 10 months, with a lifespan of about 20 years.
The Bolivian red howler is a species of howler monkey, a type of New World monkey, endemic to Bolivia. It can be found in rain forests, including riverine and seasonally flooded forests.
The mantled howler is a species of howler monkey, a type of New World monkey, from Central and South America. It is one of the monkey species most often seen and heard in the wild in Central America. It takes its "mantled" name from the long guard hairs on its sides.
The Yucatán black howler, or Guatemalan black howler, is a species of howler monkey, a type of New World monkey, from Central America. It is found in Belize, Guatemala and Mexico, in and near the Yucatán Peninsula. It lives in evergreen, semideciduous and lowland rain forests. It is also known as the baboon in Belize, although it is not closely related to the baboons in Africa.
The Guyanan red howler is a species of howler monkey, a type of New World monkey, native to Suriname, Guyana, Trinidad, French Guiana, Venezuela and Brazil.
The Mexican howler is a subspecies of the mantled howler, A. palliata. This subspecies is found predominantly in forests between south eastern Mexico and north eastern Peru. Typical of its species, the Mexican howler monkey has a prehensile tail, a deep jaw, and a large pharynx which it uses to make characteristically deep and resonating howls. Mantled howler monkeys are known for forming unusually large cohorts averaging 14 members and sometimes extending to 40 members.
The red howlers are five species of howler monkeys that used to be considered conspecific:
The ursine howler is a species of howler monkey native to Venezuela and possibly Colombia. It is sometimes considered a subspecies of the Venezuelan red howler and classified as Alouatta seniculus arctoidea.
Spix's red-handed howler is a species of Howler monkey native to the southeastern Amazon in Brazil. It is threatened by deforestation and hunting.
The southern brown howler is a monkey subspecies of brown howler native to southeastern Brazil and far northeastern Argentina (Misiones). Gregorin, 2006, considered the southern brown howler to be a separate species, Alouatta clamitans, but this has not been universally accepted.
The Juruá red howler is a species of howler monkey, native to Peru and Brazil.
The Purús red howler is a species of howler monkey native to Brazil, Peru and north of Bolivia.
Humboldt's white-fronted capuchin is a species of gracile capuchin monkey. It is found in Colombia, Venezuela, Brazil, and potentially the island of Trinidad.
