Night monkeys, also known as owl monkeys or douroucoulis, are nocturnal New World monkeys of the genus Aotus, the only member of the family Aotidae. The genus comprises eleven species which are found across Panama and much of South America in primary and secondary forests, tropical rainforests and cloud forests up to 2,400 metres (7,900 ft). Night monkeys have large eyes which improve their vision at night, while their ears are mostly hidden, giving them their name Aotus, meaning "earless".
Prosimians are a group of primates that includes all living and extinct strepsirrhines, as well as the haplorhine tarsiers and their extinct relatives, the omomyiforms, i.e. all primates excluding the simians. They are considered to have characteristics that are more "primitive" than those of simians.
The gray-bellied night monkey, also called the grey-legged douroucouli or lemurine owl monkey, is a small New World monkey of the family Aotidae. Native to tropical and subtropical forests of South America, the gray-bellied night monkey faces a significant threat from hunting, harvesting for use in pharmaceutical research and habitat destruction.
The white-eared titi monkey also known as the Bolivian titi or Bolivian gray titi, is a species of titi monkey, a type of New World monkey, from eastern Bolivia and an area of western Brazil. The species has a range that extends east from the Manique River in Beni Department, Bolivia to southern Rondônia in Brazil. The southern end of its range includes forests around the city of Santa Cruz de la Sierra.
Azara's night monkey, also known as the southern night monkey, is a night monkey species from South America. It is found in Argentina, Bolivia, Brazil, Peru and Paraguay. The species is monogamous, with the males providing a large amount of parental care. It is named after Spanish naturalist Félix de Azara. Although primarily nocturnal, some populations of Azara's night monkey are unique among night monkeys in being active both day and night. The species is listed as Least Concern on the IUCN Red List.
The Peruvian night monkey, also known as the Andean night monkey, is a nocturnal New World monkey endemic to northern Peru. Adults weigh around 1 kg (2.2 lb) and measure up to 50 cm (20 in) in length. Its colour is grey to light brown with characteristic black and white markings on the face. The chest, belly and upper arms are orange tinged, however, to a lesser extent then Aotus nigriceps.
Spix's night monkey, also known as the Colombian gray night monkey, noisy night monkey and Spix's owl monkey, is a night monkey species from South America. It is found in Brazil, Colombia, Ecuador and Peru.
The Jamaican monkey is an extinct species of New World monkey that was endemic to Jamaica. It was first uncovered at Long Mile Cave by Harold Anthony in 1920.
Brumback's night monkey is a species of night monkey found in Colombia. It has traditionally been considered a subspecies of gray-bellied night monkey, Aotus lemurinus. but it has recently been argued that it should be considered a separate species.
The evolution of color vision in primates is highly unusual compared to most eutherian mammals. A remote vertebrate ancestor of primates possessed tetrachromacy, but nocturnal, warm-blooded, mammalian ancestors lost two of four cones in the retina at the time of dinosaurs. Most teleost fish, reptiles and birds are therefore tetrachromatic while most mammals are strictly dichromats, the exceptions being some primates and marsupials, who are trichromats, and many marine mammals, who are monochromats.
Xenotrichini is a tribe of extinct primates, which lived on the Greater Antilles as recently as the 16th century.
The Panamanian night monkey or Chocoan night monkey is a species of night monkey formerly considered a subspecies of the gray-bellied night monkey of the family Aotidae. Its range consists of Panama and the Chocó region of Colombia. There are also unconfirmed reports of its occurrence in Costa Rica, especially on the Caribbean coast of Costa Rica. The species definitely occurs in the Atlantic lowlands of Panama close to the Costa Rica border.
The gray-handed night monkey is a species of night monkey formerly considered a subspecies of Gray-bellied night monkey of the family Aotidae. Its range consists of parts of Colombia and Venezuela. The exact classification of the gray-handed night monkey is uncertain. While some authors consider it a subspecies of the gray-bellied night monkey, A. lemurinus, other authors consider it a separate species, A. griseimembra.
Aotus dindensis is an extinct species of New World monkeys in the genus Aotus from the Middle Miocene. Its remains have been found at the Konzentrat-Lagerstätte of La Venta in the Honda Group of Colombia.
Lagonimico is an extinct genus of New World monkeys from the Middle Miocene. Its remains have been found at the Konzentrat-Lagerstätte of La Venta in the Honda Group of Colombia. The type species is L. conclucatus.
Micodon is an extinct genus of New World monkeys from the Middle Miocene. Its remains have been found at the Konzentrat-Lagerstätte of La Venta in the Honda Group of Colombia. The type species is M. kiotensis, a very small monkey among the New World species.
