Ceroessa
In Greek mythology, Ceroessa (Ancient Greek: Κερόεσσα, romanized: Keróessa, lit. 'the horned') was a heroine of the foundational myth of Byzantium. She was the daughter of Io and Zeus; elder sister of Epaphus; and mother of Byzas, founder of Byzantium, with her uncle, Poseidon. Creusa was Keroessa's misnomer in the Etymologicum Magnum.