Biology
The Orange-Lipped Monkey the Congo Was Hiding — A Textbook Cryptic Species
High in the rainforest canopy of the Democratic Republic of Congo, a black monkey with a striking pinkish-orange mouth has been confirmed as a new species. Named Colobus congoensis — and known locally as "Likweli" — it is only the fifth new African monkey species scientists have formally described in 75 years. The story is not just a find; it is a modern textbook case of cryptic speciation.
Found in 2008, proven much later
The animals were first photographed in 2008 in Lomami National Park, near the Congo's Lomami River. For years they remained a curiosity: a colobus-looking monkey whose orange lips did not quite match any known species. Confirming a new species requires more than a photo. Researchers had to collect specimens, examine DNA, compare calls, and rule out the possibility that the animals were merely a colour variant of an existing species. The final confirmation was published in PLOS ONE.
What makes a cryptic species
A cryptic species is one that looks so similar to a known relative that the two have been treated as a single species until genetic analysis separates them. Colobus congoensis illustrates why modern taxonomy relies on DNA as much as appearance. The species has a recognisable face mask and a deep, resonant roaring call, but its closest lookalikes live on the other side of the Lomami River. That river acts as a natural barrier: two populations of nearly identical monkeys went their separate ways on either bank, and over time genetic differences accumulated enough to define a second, distinct species.
Why rare discoveries still happen
Confirming only five new African monkey species in three-quarters of a century sounds low, but Africa's tropical forests remain one of the least-examined places on Earth for canopy primates. Animals that live entirely in the treetops, in thick forest, and in politically difficult regions are easy to miss. The conservation implication is the usual one: a species so recently confirmed may already be at risk before it is fully known, since its entire population sits inside a single protected area.
Knowledge takeaway: Colobus congoensis is the fifth new African monkey species in 75 years; cryptic species are separated by DNA and geography rather than obvious appearance; the Lomami River isolated the two colobus populations long enough for them to diverge.