Triton

Question: Did Triton have a Roman form?

Triton is a Greek god that was also worshiped by the Romans under the same name.  Triton is typically shown with a fish tail, and he oversaw some sea people known as "Tritons," which were essentially merpeople.  Other cultures have some form of merpeople, but Greek Tritons are clearly one of the main sources for myths of fish-tailed humans living in the depths of the oceans.  It seems that Triton was once the god of the sea in some regions of Greece.  As worship of Poseidon became dominant, mythology transformed Triton from being a rival god to being a son of Poseidon.  Triton looks really cool, and he was a frequent subject of Renaissance sculpture, particularly in Italy.