Herakles captures the Kerkopes - images from Wiki Commons
THE KERKOPES (Cercopes) were a pair of monkey-like thieves which plagued the land of Lydia in western Anatolia. They were once captured by Herakles who was so amused with their jokes that he set them free unharmed. The pair later ran afoul of the god Zeus who transformed them into monkeys, or else turned them to stone, as punishment for their crimes. The Kerkopes were sons of the Titan Okeanos (Oceanus) by Theia, a daughter of the Aithiopian (Ethiopian) king Memnon. (source)
Lekythis, Oxford - Ashmolean museum inv.V249 (550-500 a.C.) (source)
Bronze shield band relief, 6th century BC, and sketch. Berlin Archeological Institute B975 © Archeological Institute. Berlin (source, source)
Heracles (between Hermes and Athena) carrying the Cercopes. Wilhelm Heinrich Roscher (Göttingen, 1845- Dresden, 1923), Ausfürliches Lexikon der griechisches und römisches Mythologie, 1884. (source, source)