In Greek mythology, Aegialeia or Aegialia (Ancient Greek Αἰγιάλεια) is the Adrastid princess who becomes wife of Diomedes at Argos. Homer names her daughter of Adrastus; later authors variously make her daughter of Adrastus and Amphithea or of Aegialeus, and after Troy her adultery drives Diomedes from Argos to Italy.
Adapted from Wikipedia, "Aegiale (wife of Diomedes)" · CC BY-SA 4.0
I.Wife of Diomedes
Homer (Iliad 5.412) and Apollodorus know Aegialeia as daughter of Adrastus and wife of Diomedes. Rival stemmata make her daughter of Aegialeus son of Adrastus — hence Adrastine — securing Diomedes' hold on the Argive throne after the Epigoni.
On his return from Troy Diomedes finds her living in adultery with Cometes (and, in some tellings, others such as Hippolytus). He blames Aphrodite, whom he had wounded at Troy; when Aegialeia threatens his life he flees to Italy. Dictys Cretensis adds a Clytemnestra-like rumour that he was bringing a Trojan wife home. Ovid makes her the type of a bad wife.
II.Homonym care
The atlas id aegialia-adrastid is Diomedes' queen alone — not the beetle genus Aegialia, nor Aegiale daughter of Helios, nor the city-name Aegialeia.