What is "pelasgus"

In Greek mythology, Pelasgus was the eponymous ancestor of the Pelasgians, the mythical inhabitants of Greece who established the worship of the Dodonaean Zeus, Hephaestus, the Cabeiri, and other divinities. In the different parts of the country once occupied by Pelasgians, there existed different traditions as to the origin and connection of Pelasgus. The ancient Greeks even used to believe that he was the first man.

Pelasgus is a genus of cyprinid fishes that is only found in the Balkans. There are currently seven described species in this genus.