Horny find uncovers Triceratops' predecessor

Two enormous heads arrayed with horns are the first striking images of a pair of newly discovered dinosaur species.

The ornate heads belong to Kosmoceratops richardsoni and the Utahceratops gettyi, two species of dinosaur found in southern Utah's Grand-Staircase-Escalante National Monument.

Both Kosmoceratops and Utahceratops were plant-eating inhabitants of the 'long lost continent' of Laramidia about 76 million years ago, says Dr Eric Roberts, one of the scientists involved in the discovery, who is now based at James Cook University in Townsville.

"The two dinosaurs are relatives of the famous Triceratops but they are about 10 million years older," says Roberts.

He says it's particularly exciting because they are among the first of many dinosaur discoveries being made in the region.

"The area we're working in is yielding a whole slew of other dinosaurs as well," says Roberts.

"This pair is from a whole amazing range of discoveries, from other dinosaurs to other mammals."

The two new dinosaurs have a much more elaborate array of horns than the more familiar Triceratops, with the smaller of the two, Kosmoceratops, baring 15 of different shapes and sizes.

It is the most ornate dinosaur head yet discovered ('kosmos' is Greek for ornate). The discoverers speculate that rather than being used for fighting, the horns may have been for decoration and advantage in courtship displays, as well as to deter mating rivals.

The Utahceratops doesn't have so many horns, but is distinguished with a massive head - its skull measuring 2.3 metres long. It is said to resemble a giant rhino with a supersized head.