Oplosaurus

Oplosaurus is known only from a single tooth, found in the 1850s. This tooth is 85 mm (3.35 inches) tall, about as long as a credit card.12

The tooth looks very similar to a Brachiosaurus tooth, so scientists think Oplosaurus was a giant sauropod, maybe 25 metres (82 feet) long.12

Its name means 'armed lizard' or 'weapon lizard', probably because the tooth looked like a weapon. The species name armatus also means 'armed' in Latin.1

Some scientists think Oplosaurus might have been a turiasaur, a group of primitive sauropods with heart-shaped teeth. Others place it in the Camarasauridae family.1

The tooth has a pointed tip and wear facets from grinding plants. This shows Oplosaurus was a plant-eater that chewed its food.1

Oplosaurus lived on the Isle of Wight when it was a low plain with rivers and lakes. The climate was warm and humid, like a subtropical forest.1

Because only one tooth has been found, Oplosaurus is a 'tooth taxon'. Scientists are not sure if it is a valid genus or if the tooth belongs to another dinosaur like Pelorosaurus.12