Volvagia

destroyer of cities, eater of gorons, frier of grass and cute flowers. Volvagia is the boss residing in the Fire Temple. The fierce dragon, measuring... some kind of distance between head and the tip of his tail, can only be killed with the legendary Megaton Hammer (Or plain stupid arrows). Some claim that he actually is a Leviathan, since he hasn't got any wings and does something more of a glide/swim-thing through the hot fumes of his lair. another legend about the beast is that he has some kind of relation to the great Valoo, the sage of the Rito. Relatives? Who knows?

http://www.zeldauniverse.net/gallery/albums/officialart/oot/bosses/volvagia.gif