By Megan Shersby

Published: Thursday, 22 December 2022 at 12:00 am


The titles for the smallest primate and smallest monkey go to different species, as not all primates are monkeys. As well as monkeys, primates also include the prosimians (such as lemurs), lesser apes (the gibbons), great apes (such as orangutans and gorillas) and humans.

What is the smallest monkey in the world?

The smallest monkey in the world accolade is awarded to two species of pygmy marmoset, found in South America, including Bolivia, Brazil, Columbia, Ecuador, and Peru.

The two – the Western pygmy marmoset (Cebuella pygmaea) and the Eastern pygmy marmoset (C. niveiventris) – used to be considered two subspecies of the same species, but a scientific paper published in Molecular Phylogenetics and Evolution in 2018 split them into two separate species. The two are very similar in morphology, and are separated by geographical barriers such as large rivers.

Pygmy marmosets weigh just over 100g, and measure between 11.7-15.2cm in head-body length.

What is the smallest primate in the world?