Zis Menzanas, known in Latin sources as Iuppiter Menzanas, is the horse-lord aspect of the Messapic sky-god Zis. The epithet menzanas preserves an inherited Palaeo-Balkan word for the horse (compare Albanian mëz 'foal'), and the deity is best known from a notice of the Roman grammarian Festus reporting that the Sallentini of southern Apulia annually sacrificed a horse to him by throwing the living animal into a fire. The cult-title binds the supreme sky-god to the horse, an animal central to Iapygian aristocratic and ritual life, and is the clearest surviving evidence for a distinctively Messapian sacrificial practice.