Types of Monkeys: Old World vs New World and 330+ Species
Monkeys are broadly classified into two main types, Old World monkeys and New World monkeys, based on their physical traits, habitats, and evolutionary history. With more than 330 species found across tropical regions of the world, these groups include everything from ground dwelling baboons in Africa to tree living spider monkeys in the Amazon.
Monkeys belong to the primate order, a group of mammals that also includes apes, lemurs, and tarsiers. Within this order, monkeys represent a major branch that evolved distinct physical traits and behaviors, setting them apart from other primates.
Main Types of Monkeys
Monkeys are classified into two main types based on their anatomy, geographic distribution, and evolutionary lineage. Understanding these two groups makes it easier to identify and compare monkey species across the world.
What are the main types of monkeys?
The two main types of monkeys are:
- Old World monkeys
- New World monkeys
Old World monkeys are found in Africa and Asia, while New World monkeys live in Central and South America.
For a detailed comparison, see:
Old World Monkeys Vs. New World Monkeys
List of Common Monkey Types
While there are hundreds of monkey species, most belong to a few well known groups that people commonly refer to when talking about types of monkeys. The list below highlights the most recognizable and widely studied monkey groups.
Complete List of Monkey Species
Monkeys are listed alphabetically below. Each section shows a few examples, with links to full lists for each letter.
Monkeys Starting with A
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Monkeys Starting with B
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Monkeys Starting with C
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Monkeys Starting with D
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Monkeys Starting with E
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Monkeys Starting with F
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Monkeys Starting with G
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Monkeys Starting with H
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Monkeys Starting with I
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Monkeys Starting with J
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Monkeys Starting with K
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Monkeys Starting with L
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Monkeys Starting with M
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Monkeys Starting with N
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Monkeys Starting with O
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Monkeys Starting with P
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Monkeys Starting with R
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Monkeys Starting with S
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Monkeys Starting with T
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Monkeys Starting with U
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Monkeys Starting with V
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Monkeys Starting with W
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Monkeys Starting with Y
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Monkeys Starting with Z
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Are Gorillas Monkeys?
Not all primates are monkeys!
It’s crucial to note that while all monkeys are primates, not all primates are monkeys. Prosimians (including lemurs, lorises, and tarsiers) and apes (both great and lesser) are distinct groups within the primate order and are not classified as monkeys. This common misconception often leads to confusion, but understanding these distinctions is key to appreciating the diversity of the primate family tree.
Classification of Primates
Here are 4 major types of primate and their characteristics:
Prosimians
These prosimian species live today, including lemurs, lorises, tarsiers, aye-aye, and bush babies. The prosimians were classified into order Primates mainly because their hands with flexible fingers and opposable thumbs made it possible to fetch things up.
Most prosimians rely heavily on a sense of smell for communication and finding food. With the tarsier, eyesight has become more critical as it can swivel its head 180 degrees in each direction. On the other hand, the apes and monkeys rely primarily on their sight.
Today, Prosimians live in some parts of Asia and Africa, especially Madagascar. No prosimian species are found in the Americas or Australia.
Old World Monkeys
All Old World monkeys are classified under two families: Cercopithecinae and Colobinae.
Unique characteristics-wise, Old World monkeys have downward-pointing nostrils, tend to stay mainly on the ground than trees (non-arboreal), and have a simple digestive system with cheek pouches for plant matters. Also, these primates have a tail which makes them different from apes.
The Old World monkeys hail from various countries in South and East Asia, the Middle East, and Africa, except for Madagascar.
New World Monkeys
These primates are restricted to the tropical forests of Southern Mexico and Central and Latin America.
Taxonomically, New World monkeys are classified into two prominent families Cebidae and Callitricidae.
Exclusive attributes-wise, these kinds of monkeys are primarily herbivores, twin births, and no-cheek-pouches unlike Old World counterparts, and some have a prehensile tail (Spider monkeys).
Apes
Apes do not have tails (except L’Hoest monkey – a great ape) due to the mutation of the TXBT[4] gene cell.
Also, apes cannot perform brachiation (arm swinging in the arboreal movements on tree tops, unlike the other three kinds listed above).
There are two main branches of apes: gibbons (“lesser apes”) and hominids (“great apes”). Orangutans, gorillas, chimpanzees, and bonobos are examples of greater apes, whereas the lesser apes contain all types of gibbons, including Lar gibbon, Agile gibbon, Silvery gibbon, and more.
Hominoids are swift tree climbers except for gorillas and humans. Apes feed on various plants such as fruits, leaves, stalks, seeds, roots, and small animals.
Monkeys vs. Monkies
Let’s get one of the fundamental confusion out of the way first. Is it monkeys or monkies?
When a noun word ends with “y”, there is always confusion as to whether the plural form ends with “ies” or “ys”.
Many English dictionary sources say the grammar rule is simple. When a noun ends with a vowel followed by y, the plural form gets an “s”; otherwise, it would end with “ies”.
For instance, the plural form of “Dictionary” is “Dictionaries”.
Based on that principle, the plural form of monkey is indeed monkeys.
First Grouping of Primates
An English biologist, St. George Jackson Mivart first published the classification of primates in his book ‘Man and Apes’ in 1873[1]. His categorization of monkeys was based purely on anatomical differences, habits, and geographical distribution. According to this book, the early classification of order Primates contained two sub-groups, namely:
- Group-1: Man, and all the apes, which were first called Anthropoidea.
- Group-2: All Lemurs and the animals most like them were called Lemuroidea; the creatures contained in it when spoken of being generally also termed “Half-apes” or “Lemuroids“.
Modern Grouping of Primates
After so many debates and further data collection and analyses and discoveries of new monkey species over a century, another British-born biological anthropologist, Robert D. Martin, currently a curator at Chicago Natural Museum, has published an excellent book called “Primate Origins and Evolution: A Phylogenetic Reconstruction” in 1994[2]. This research attempted to classify living primates into 6 different sub-groups based on geographical importance.
| # | Primate Groupings | Geographical Region | Collectively Called |
|---|---|---|---|
| 1 | Lemurs | Madagascar | |
| 2 | Lorises and bushbabies | Africa and Asia | Prosimians |
| 3 | Tarsiers | Southeast Asia | |
| 4 | Marmosets, Tamarins, Capuchins, Squirrel monkeys, Owl monkeys, Titis, Sakis, and Howlers (Ceboidea) | South and Latin America | New World Monkeys |
| 5 | Talapoins, Guenons, Baboons, Colobus, Macaques, Vervets, Geladas, Mangabeys, Langurs, Mandrills, Surili, Patas, Proboscis Monkeys (Cercopithecoids meaning “elongated apes“) | Africa and Asia | Old World Monkeys |
| 6 | Apes and humans (Hominoids) | Africa and Asia | Apes |
This primate grouping is based on grade or level of organization, and in no way does it implies any superiority or inferiority between them.
According to the fossil study in Tanzania by paleontologists in 2013[3], it became evident that the old World monkeys (baboons, macaques) and apes (humans & chimpanzees) were already separated 25 million years ago!
Frequently Asked Questions
The Rhesus macaque is one of the most common monkeys, especially in Asia. Found in diverse habitats, from grasslands to urban areas, they have a wide distribution. Another prevalent species is the Vervet monkey, native to Africa and known for its adaptability to various environments.
The capuchin monkey is often considered the friendliest among monkey species. Renowned for its sociable behavior, intelligence, and playful nature, it frequently interacts positively with humans, making it a popular choice in the pet trade and entertainment industries. However, like all primates, they have complex needs and can be challenging to care for.
A monkey that starts with “G” is the “Golden lion tamarin“. It’s a small New World monkey known for its bright reddish-orange fur and mane, resembling a lion’s. They are native to the Atlantic coastal forests of Brazil.
The two types of monkeys are:
Old World Monkeys: Native to Africa and Asia, they include species like baboons, macaques, and colobus monkeys.
New World Monkeys: Found in Central and South America, they include capuchins, howler monkeys, and tamarins.
As of 2026, there are over 330 different species of monkeys in the world, classified into two main groups: Old World Monkeys and New World Monkeys.
The smallest monkey is the pygmy marmoset (Cebuella pygmaea). It weighs around 100 grams (3.5 ounces) and measures about 4.6 to 6.2 inches (11.7 to 15.8 cm) in length, excluding its tail. Native to the rainforests of the western Amazon Basin in South America, pygmy marmosets are known for their tiny size and distinctive vocalizations.
Types of Monkeys By Diet
Types of Monkeys By Colors
Types of Monkeys By Habitats
Types of Rainforest Monkeys
Types of Monkeys By Countries
Cite this page
Bio Explorer. (2026, May 4). Types of Monkeys: Old World vs New World and 330+ Species. https://www.bioexplorer.net/animals/mammals/monkeys/
As someone with a background in primate classification, I appreciate how clearly this page distinguishes between Old World and New World monkeys using both anatomical traits and geographic distribution. The emphasis on features like nostril orientation, tail function, and habitat makes the classification intuitive without oversimplifying it. The alphabetical listing is also a strong addition, it bridges the gap between taxonomy and practical identification, which many resources fail to do. One enhancement that could make this even stronger would be a quick comparison table summarizing key diagnostic traits across major groups for faster reference.
I always thought monkeys were just one big group, so the distinction between Old World and New World monkeys was new to me. The explanation here made it really easy to understand, especially the part about where they live and how their features differ. The alphabetical list is also helpful when you’re trying to look up specific species. Quick question: are there any monkeys that don’t clearly fit into either group, or is the classification always this straightforward?