In Greek mythology, Iasus (Iasos) is a king of Argos named in several strands as father of Io. Apollodorus makes him son of Argus and Ismene; Pausanias' Argive succession makes him son of Triopas. Castor and many tragedians instead call Io daughter of Inachus — a documented dispute. Distinct from Iasus of Arcadia (Atalanta's father) and from the Athenian captain slain by Aeneas.
Adapted from Wikipedia, "Iasus" · CC BY-SA 4.0
I.Father of Io
Apollodorus reports that Argus and Ismene, daughter of Asopus, had a son Iasus who is said to have been the father of Io — while noting that Castor and many tragedians make Io daughter of Inachus, and Hesiod and Acusilaus daughter of Piren.
Pausanias' native Argive king-list places an Iasus son of Triopas in the royal line that leads toward Io's generation. The atlas tags the clash under the topic io-paternity.
II.Homonym care
Iasus of Arcadia (iasus-arcadia), son of Lycurgus and father of Atalanta by Clymene, is a separate house already documented. Homer's Iasus son of Sphelus, Athenian captain killed by Aeneas at the ships, is iasus-athenian.
The id iasus-argive holds only the Argive king tied to Io's disputed paternity.