In Greek mythology, Cyanippus (Ancient Greek Κυάνιππος) is the last king named in the Biantid / Adrastid succession at Argos. Apollodorus makes him son of Adrastus and brother of Aegialeus; Pausanias calls him son of Aegialeus and Comaetho. He fights at Troy (and enters the Horse in Tryphiodorus), dies childless, and is succeeded by Cylarabes.
Adapted from Wikipedia, "Cyanippus" · CC BY-SA 4.0
I.Last of the Adrastid line at Argos
Pausanias (2.18.4–5; 2.30.10) makes Cyanippus son of Aegialeus; Apollodorus (1.9.13) makes him son of Adrastus and Amphithea and brother of Aegialeus. He rules Argos for a time, fights in the Trojan War, and in Tryphiodorus is among those who enter the Wooden Horse. Dying without children, he leaves the reunited kingdom to Cylarabes son of Sthenelus — closing the Melampid–Biantid–Anaxagorid partition.
Wikipedia's disambiguation also lists a Thessalian Cyanippus (Parthenius' Leucone tale) and a Syracusan punished by Dionysus — neither is this Argive Adrastid.
II.Homonym care
The atlas id cyanippus-adrastid is the Argive king alone. Distinct from Parthenius' Thessalian hunter and from Pseudo-Plutarch's Syracusan Cyanippus.