Scientists have identified a new monkey species, Colobus congoensis, in the Democratic Republic of Congo’s Lomami Basin, the same forest that yielded a new primate in 2012.
The monkey, known locally as Likweli, carries a glossy black coat, orange cream patches around its mouth and nose, and a roaring call that differs in sequence and frequency from its closest known relative. It weighs about 15 pounds, smaller than other Colobus monkeys, and researchers found distinct skull, teeth and skeletal traits separating it from every known African colobus species.
Kate Detwiler of Florida Atlantic University and Christopher Gilbert of the City University of New York Graduate Center and Hunter College led the study, published in PLOS ONE with contributions from Yale researchers. Detwiler also co-authored the 2012 description of Lesula, another previously unknown monkey species found in the same Lomami Basin region, making Likweli the second new primate she has helped confirm from that stretch of forest, now protected as Lomami National Park.
Conservationists with the Lukuru Wildlife Research Foundation first photographed the animal in 2008, years before the park’s 2016 creation. A clearer sighting followed a decade later, and researchers logged 114 field observations between 2018 and 2022 across an estimated range of 1,700 square kilometers.
Genetic testing traced Likweli’s closest relative to Colobus satanas, a species living more than 1,200 kilometers west. The two lineages share a common ancestor from roughly 4.7 million to 5.8 million years ago, the oldest known split inside the Colobus family tree.
Local naming reflects how little the species was known even nearby. Bangala communities call it Likweli, while Mituku residents use kasaba nkoni, meaning branch shaker. Researchers surveyed 52 villages bordering the range and found only eight where residents could describe the animal, helping explain why it went undocumented for so long despite sitting inside a national park.
Detwiler said the evidence pointed clearly toward a new species. Researchers are recommending an Endangered listing given the limited range, habitat loss and hunting pressure, and note that most of the population lives within Lomami National Park’s boundaries.
Alexander Georgiev, a primatologist at Bangor University who was not involved in the study, called the analysis thorough and said finding a primate unfamiliar even to local residents is rare. Likweli is only the fifth new monkey species documented in Africa in 75 years.
