Bronto Thunder (Voiced by Marvin Goldhar) is a member of the Dinosaucers. He is somewhat naive, a trait that sometimes gets him into trouble or interferes with the missions of the Dinosaucers as a whole.
Bronto Thunder is an evolved Apatosaurus, a giant herbivore and a sauropod that lived at the Late Jurassic period, 150 millon years ago.He is thought to be second-in-command among the Dinosaucers, as he often takes command when Allo is absent or away from Lavadome. Although this is heavily implied, it is nevertheless never directly stated and perhaps no Dinosaucer within the group exerts such a function.
Bronto Thunder's name is an example of tautology, as "Bronto" means "Thunder" in ancient greek. He is physically considered the strongest of the Dinosaucers and he is the largest of the group.He can Dinovolve into an 80 foot or 24 meters long Apatosaurus. At this form and size, he is the most destructive Dinosaucer, able to trash everything in his path or crush almost anything standing in his way. He also dinovolves in order to help his friends cross a large extense of terrain when it is inacessible or too steep for his comrades, or to get through situations where only sheer size can help out.
Bronto Thunder's spaceship does not closley resemble an apatosarus, but it has the unique ability to burrow under the ground. This ability was used in a few episodes.