Titanosaurus (チタノザウルス, Chitanozaurusu) is a giant aquatic dinosaur used as a pawn in the Black Hole Aliens' invasion of Earth that appeared in the 1975 film Terror of Mechagodzilla.
Titanosaurus resembles a gigantic bipedal dinosaurian creature with warty red flesh and fins on his neck, back, and tail. Titanosaurus is 60 meters tall, 100 meters long, and weighs 30,000 tons.
Titanosaurus was a peaceful sea-dwelling creature that was discovered by marine biologist Shinzo Mafune. Mafune discovered a way to control Titanosaurus remotely and announced his discovery to the scientific community. Mafune's colleagues dismissed him as insane and he was fired from the institute at which he worked. Disgruntled, Mafune and his daughter Katsura resumed experiments on controlling Titanosaurus and eventually decided to use the monster as the instrument of his revenge against humanity for shunning him. Mafune joined forces with the Black Hole Aliens, offering them the services of Titanosaurus as an ally of Mechagodzilla.