Urulóki
From Tolkien Gateway
Urulóki were also known as Fire-drakes, fire breathing Dragons. Glaurung, the Father of Dragons, was the first of the species. He first appeared in the middle of the First Age but the Urulóki were known to have survived even after the downfall of Morgoth.
Ancalagon was also considered of the Urulóki, as was Smaug who may have been the last of the great Urulóki. Other lesser dragons were recorded as having survived after the end of the Third Age.
