Black-and-white colobus are Old World monkeys of the genus Colobus, native to Africa, and are closely related to the red colobus
monkeys of genus Piliocolobus. The word "colobus" comes from Greek ekolobóse "he cut short" and is so named because its thumb
is a stump.
The gray langurs are a group of Old World monkeys and make up the entirety of the genus Semnopithecus. Gray langurs are large
and fairly terrestrial, inhabiting open wooded habitats and urban areas on the Indian subcontinent. Until recently they were
considered one species, Semnopithecus entellus; now seven distinct species are recognized. When only one species was recognized,
it was also called the Hanuman Langur, the Common Langur and the Entellus Langur.
The red colobus are Old World monkeys of the genus Piliocolobus. They were formerly placed in the genus Procolobus, which
now is limited to the Olive Colobus. They are closely related to the black-and-white colobus monkeys (genus Colobus) and some
species are often found in groups with the Blue Monkey. The Western Red Colobus is frequently hunted by the Common Chimpanzee.
The lutungs are a group of Old World monkeys and make up the entirety of the genus Trachypithecus. Their range is split into
two parts; one part is much of southeast Asia, the other part is extreme southern India and Sri Lanka. The majority of India
has no lutungs. Most of the species in this genus can be referred to as lutungs, as langurs, or as leaf monkeys. Lutungs have
a rather slim build with a long tail. The fur coloring varies depending upon species from black and grey to orange yellow.
The Proboscis Monkey (Nasalis larvatus) is also known as the Monyet Belanda in Malay, the Bekantan in Indonesian or simply
the Long-nosed Monkey. It is a reddish-brown arboreal Old World monkey that is endemic to the south-east Asian island of Borneo.
It belongs in the monotypic genus Nasalis, although the Pig-tailed Langur has traditionally also been included in this genus
- a treatment still preferred by some.
The Mantled Guereza (Colobus guereza), also known simply as the Guereza, the Eastern Black-and-white Colobus, or the Abyssinian
Black-and-white Colobus, is a colobus monkey, a kind of Old World monkey. It is native to much of west central and east Africa,
including Cameroon, Equatorial Guinea, Nigeria, Ethiopia, Kenya, Tanzania, Uganda and Chad.
