Callirhoe (daughter of Achelous)

Naiad daughter of Achelous, second wife of Alcmaeon — she demands Harmonia's necklace and robe, then prays Zeus for sons who will avenge their father. Not the Oceanid Callirhoe nor the Calydonian spring-nymph of the same name.

Alcmaeon (mythology)

Callirhoe's husband after his purification by Achelous — the Epigoni matricide whose second marriage ends in the necklace's deadly demand.

Alcmaeon in Corinth

Euripides

Euripides' posthumous tragedy of Alcmaeon's children — the Corinthian recognition play that keeps Callirhoe's line in Attic drama.

Achelous

Callirhoe's river-god father — the Aetolian stream who purifies Alcmaeon and gives him his daughter.