New orange-lipped monkey found: Scientists identify Colobus congoensis, a species that roars & snorts loudly in the Congo rainforest

Scientists have identified a previously unknown species of monkey with striking orange lips, mask-like facial markings and distinctive roaring calls in the rainforests of the Democratic Republic of the Congo (DRC). The discovery is being hailed as one of the most significant primate finds in decades and could reshape scientists' understanding of African monkey evolution.

According to Live Science, the newly described species has been named Colobus congoensis after the Congo region. Locally, it is known as "likweli", a name used by the Balanga people living near its habitat.

The findings were published on 15 July in the peer-reviewed journal PLOS One.

One of only a handful of new African monkey species discovered in decades

Researchers say Colobus congoensis is only the fifth new monkey species identified in Africa in the past 75 years, making the discovery particularly rare.

Joshua Linder, an anthropologist and president of conservation organisation The Forest Collective, described the find as remarkable because discovering a previously undocumented primate species of this size is highly unusual today.

Researchers also believe that the Congo Basin could still harbour other unknown primate species.

How scientists found the mysterious monkey

The mystery began in 2008, when conservationists photographed an unidentified monkey in the dense forests of Lomami National Park, although the animal was partly hidden.

A clearer sighting in 2018 prompted Junior Amboko, a researcher at Lomami National Park and anthropologist at Florida Atlantic University, to investigate further.

The research team showed photographs of the unknown monkey to people in 52 villages surrounding the park.

Only hunters from eight villages recognised the animal, suggesting it was extremely rare and known only within a limited area.

Where does the new monkey live?

Researchers recorded 114 sightings of the species between 2018 and 2022.

According to Live Science, the monkey occupies an estimated range of around 1,700 square kilometres, naturally enclosed between the Lomami and Lualaba rivers in the Democratic Republic of the Congo.

The animals were observed living in groups ranging from one to 20 individuals.

What makes Colobus congoensis unique?

The newly discovered monkey stands out because of several distinctive physical characteristics.

Researchers describe it as having:

• Bright orange fur around the mouth and nose
• Bare grey skin on the cheeks, giving it a mask-like appearance
• Glossy black fur across most of the body
• A conspicuous white patch beneath the tail
• An average weight of about 7 kilograms

According to Live Science, these facial markings and rump colouring help distinguish the species from all other known colobus monkeys.

The monkey also makes unusual roaring sounds

Appearance is not the only feature that sets the species apart. Researchers found that Colobus congoensis produces deep, booming roars accompanied by distinctive snorting sounds.

These vocalisations differ significantly from those of other colobus monkeys and became another important clue confirming that the animal represented a separate species.

DNA analysis confirmed it was a new species

To verify the discovery, scientists analysed DNA from tissue samples obtained from monkeys intercepted from the illegal bushmeat trade.

The genetic material was compared with museum collections and scientific databases containing information on other colobus monkeys, including skulls, teeth, pelts and DNA.

According to Live Science, the mitochondrial DNA showed the monkey was genetically distinct from every previously recognised colobus species.

Researchers described the level of genetic divergence as unexpectedly large.

Discovery could reshape African monkey evolution

One of the study's most surprising findings concerns the monkey's closest living relative.

Although Colobus congoensis lives alongside the Angola colobus (Colobus angolensis), genetic analysis showed its nearest relative is actually the black colobus (Colobus satanas), found around 1,200 kilometres away in Cameroon, Gabon and Bioko Island.

Researchers estimate the two species diverged between 5.78 million and 3.44 million years ago, representing the longest known evolutionary split within the Colobus genus.

Scientists believe this discovery could significantly improve understanding of primate evolution across Africa.

Researchers recommend endangered status

Because the newly identified monkey occupies a relatively small geographic range and faces increasing habitat loss, researchers recommend that Colobus congoensis be classified as Endangered on the IUCN Red List.

They say protecting the forests of Lomami National Park will be essential for the species' long-term survival.

Inputs from agencies