The lesula (Cercopithecus lomamiensis) is a species of Old World monkey in the guenon family, found in the Lomami Basin of the Congo. Though known to locals, it was unknown to the international scientific community until it was discovered in 2007 and confirmed in a 2012 publication.

The lesula is the second new species of African monkey to be discovered since 1984. This monkey is described to have human looking eyes and a blue bottom "And adult males have a huge bare patch of skin in the buttocks, testicles and perianal area," said John A. Hart, the researcher who described the monkey. "It's a brilliant blue, really pretty spectacular."