New monkey species with orange lips and frog-like call discovered in DR Congo

A long-awaited discovery

Conservationists working in the dense rainforest of what is now Lomami National Park first photographed an unusual monkey in 2008, but the image was too blurry to draw conclusions. A second, clearer sighting in 2018 finally gave researchers enough to act on. An international team from the Democratic Republic of the Congo, the United States, and Germany then spent four years tracking the animal, combining field surveys, audio recordings, and genetic sampling. Their results, published on 15 July 2026 in PLOS One, confirm that the primate is a species new to science. It is only the fifth new African monkey species identified in the past 75 years.

What the likweli looks and sounds like

The monkey has glossy black fur, a long curved tail, and a striking facial pattern: grey cheeks, a dark mask around the eyes, and pinkish-orange lips. It belongs to the colobus group, monkeys that lack thumbs, and is smaller than its relatives, weighing about 6.8 kilograms. Its vocalisations are equally distinctive, described as a loud roar punctuated by snorts or a frog-like croak. Junior D. Amboko, the PhD student at Florida Atlantic University who led much of the fieldwork, told BBC News that it was an "incredible feeling" to look at the face of an animal so few people knew existed.

Genetic roots and evolutionary surprise

DNA analysis revealed that Colobus congoensis is most closely related to Colobus satanas, a species that lives more than 1,200 kilometres away in west-central Africa. The two lineages split between 4 and 5 million years ago, making this one of the oldest known branches within the genus Colobus. Kate Detwiler, a professor at Florida Atlantic University and co-author of the study, said the discovery "changes our understanding of African monkey evolution." The finding underscores how much remains unknown in the central Congo basin, a region that co-author John Hart called a place that "continues to shape our understanding of primate evolution and conservation."

Local knowledge and the search

Although the monkey was unknown to science, some communities living near its habitat already had a name for it: likweli. Researchers interviewed people in 52 villages and found that only those in eight of them recognised the animal. Amboko noted that the monkeys are "rather shy" and tend to hide high in the canopy, which helps explain why they remained obscure even to locals. Over the course of the study, the team logged 114 observations. Alexander Georgiev, a primatologist at Bangor University who was not involved in the work, described the research as "very thorough and convincing."

A species already at risk

The likweli's known range is confined to roughly 1,700 square kilometres of closed-canopy forest between the Lomami and Lilo rivers. That restricted distribution, combined with hunting pressure and habitat loss, has led the authors to recommend that the species be classified as Endangered on the IUCN Red List. Detwiler called the discovery a scientific triumph but also "a reminder that some of the rarest creatures on Earth could disappear before the world even knows they exist." Hart added that even in scientifically explored regions, entirely unknown species are still coming to light.