A newly discovered horned dinosaur called Titanoceratops appears to have reigned long before its more famous descendants, Triceratops and Torosaurus.
The species weighed in at around 6,800 kilograms [15,000 pounds] and an enormous 8-foot skull — rivaling Triceratops for size. It is very similar to Triceratops, but with a thinner frill, longer nose and slightly bigger horns.
Titanoceratops lived in the American Southwest during the Cretaceous period, about 74 million years ago, and is the earliest known triceratopsin. Its discovery has signalled that the group evolved its large size about 5 million years earlier than previously thought.
The discovery was made by Nicholas Longrich, a palaeontologist at Yale University and will feature in the journal Cretaceous Research.
Longrich found signs of a new triceratopsin species when he came across a description of a partial skeleton of a dinosaur unearthed in New Mexico in 1941 in scientific papers. This dinosaur was wrongly identified as Pentaceratops and reconstructed for display in the Oklahoma Museum of Natural History.
Longrich noticed that the skeleton was too different from other Pentaceratops to be the same species, because it would have belonged to a creature that could have weighed double that of an adult Pentaceratops. Instead he believes that it is a predecessor of both Triceratops and Torosaurus.
In order to confirm the discovery, Longrich is hoping that other fossil skeletons will be found with the crucial frill intact, which will help make the differences between Titanoceratops and Pentaceratops clearer.