The butterfly genus Cycnus is now synonymized with Panthiades.
In Greek mythology, multiple characters were known as Cycnus (Ancient Greek: Κύκνος) or Cygnus. The literal meaning of the name is "swan", and accordingly most of them ended up being transformed into swans.
Cycnus, son of King Eredion of Achaea, who, in one version, seduced Leda and made her mother of triplets: the Dioscuri and Helen. In all other sources, she had these children by Zeus who approached her in the shape of a swan (kyknos).
Cycnus, a blunder for Guneus in the manuscript of Hyginus' Fab. 97 (list of the Achaean leaders against Troy).
According to Pseudo-Eratosthenes and Hyginus' Poetical Astronomy, the constellation Cygnus was the stellar image of the swan Zeus had transformed into in order to seduce Leda or Nemesis.
This article includes a list of Greek mythological figures with the same or similar names. If an internal link for a specific Greek mythology article referred you to this page, you may wish to change the link to point directly to the intended Greek mythology article, if one exists.