Apis was a son of Phoroneus by the nymph Teledice,[3] or Cinna,[4] or Cerdo,[5] or Perimede[6] and brother of Niobe.
According to a scholiast on Euripides's Orestes, he was the son of Phoroneus by his first wife Peitho ("Persuasion") and brother to Niobe, Aegialeus, and Europs.
[7] Apollodorus reports that during his reign, Apis established a tyrannical government and called the Peloponnesus Apia, after his own name, and that he was eventually killed in a conspiracy headed by Thelxion, king of Sparta, and Telchis.
[9] Argus Panoptes, a descendant of his sister Niobe, avenged his murder by putting Thelxion and Telchis to death.
This confusion is still more manifest in the tradition, that Apis gave his kingdom of Argos to his brother, and went to Egypt, where he reigned for several years afterwards.