The first ever photograph of the elusive Bouvier's red colobus species of monkey has proven it is not extinct, as it has not been spotted for more than half a century. The picture, released by the Wildlife Conservation Society, shows a mother and her infant sitting in a tree.

Primatologists working in the Republic of Congo have managed to capture the monkey on camera after tracking it with help of locals familiar with red colobus vocalisations and behaviour.

Researchers Lieven Devreese and Gaël Elie Gnondo Gobolo captured the monkey on camera in the Ntokou-Pikounda National Park, a 4,572sq/km (1,765sq/m) protected area created to ensure the safety of gorillas, chimpanzees, elephants, and other species.

"Our photos are the world's first and confirm that the species is not extinct," Devreese said.

Virtually nothing is known of Bouvier's red colobus monkeys. Experts have said it could be a subspecies of the larger colobus taxonomic group, but most believe it to be a full species. It was first described in 1887 and is only known because of a few specimens in museums collected from three locations over 100 years ago.

They appear not to be afraid of humans, looking down on them from trees. However, this has caused them to become even rarer where hunters practice – they are highly threatened by demand for bushmeat in the area.

James Deutsch, vice president for conservation strategy at WCS, commented: "Confirmation that Bouvier's red colobus still thrives in the this area reminds us that there remain substantially intact wild places on Earth, and should re-energize all of us to save them before it is too late."

Fiona Maisels, also from the WCS, added: "We're very pleased indeed that Lieven and Gaël were able to achieve their objective of not only confirming that Bouvier's red colobus still exists, but also managing to get a very clear close-up picture of a mother and infant. Thankfully, many of these colobus monkeys live in the recently gazetted national park and are protected from threats such as logging, agriculture, and roads, all of which can lead to increased hunting."