Brontosaurus, meaning "thunder lizard", is a genus of sauropod dinosaurs. Originally named by its discoverer Othniel Charles Marsh in 1879, Brontosaurus had long been considered a junior synonym of Apatosaurus; its original species Brontosaurus excelsus (excelsus meaning “elevate”) was reclassified as A. excelsus in 1903. However, an extensive study published in 2015 by a joint British-Portuguese research team concluded that Brontosaurus was a valid genus of sauropod distinct from Apatosaurus. Nevertheless, not all paleontologists agree with this division.
The only episode to show at least 1 Brontosaurus was "Dinosaurs". A female Brontosaurus was the first dinosaur shown in that episode. She was also the only dinosaur to have similarities with 2 different animals (she has 4 legs like a monitor lizard, and a long neck like an emu).
- Like other dinosaurs in the series, this species is computer animated (due to being extinct), making all individuals of the same species (male and female) look exactly the same.
- The Martinandchrissaurus had the body of a Brontosaurus.