An international team of scientists, including Yale researchers, has described a new Colobus monkey species inhabiting high forest canopies in the Democratic Republic of Congo (DRC). It is just the fifth new species of African monkey discovered in the past 75 years.

The species, Colobus congoensis, is a rare and cryptic monkey largely unknown even among people living within its range. But those who are familiar with the small, black monkeys — an arboreal creature marked by distinctive orange-cream patches around their mouths and noses — call them “Likweli,” which the researchers recommend remain the species’ common name.

The identification of Likweli as distinct from other Colobus monkey species is supported by evidence drawn from its physical traits, genetics, and vocalizations.  

“Our team evaluated multiple datasets that all reached the same conclusion: Likweli is a distinct species of Colobus monkey we haven’t seen before,” said Julia Arenson, a postdoctoral fellow in Yale’s Department of Anthropology and the Yale Institute for Biospheric Studies and coauthor of the study. “Discovering a primate species is exceptionally rare, especially from populations previously unknown to science.”