The Lesser spot-nosed monkey (Cercopithecus petaurista) is a species of guenon distributed in the coastal countries of West Africa. It favors arboreal environments such as riverside forests and plantations, and lives by eating leaves, fruit, flowers, and insects. It forms small groups of about 10 individuals, and is known for a distinctive visual communication called “head-flagging” that uses the white heart-shaped marking on the tip of the nose. Because it is widely distributed it is currently assessed as Least Concern, but the full extent of its population is unknown.