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Paleontologists at the University of Bristol have officially identified a new species of dinosaur from Triassic fossil beds in South Wales, near Penarth—more than 125 years after the specimen was initially reported.

Using modern digital scanning techniques, the researchers were able to shed new light on the fossil jawbone, which has been known since 1899 and been on display in the National Museum of Wales for many years, but was not correctly identified until now.

The , "Re-assessment of a large theropod dinosaur dentary from the Rhaetian of South Wales," is published in the Proceedings of the Geologists' Association.

The fossil consists of natural molds of the jawbone in the rock and all the original bone has disappeared. So, using photo scanning, paleontology student Owain Evans was able to make a perfect 3D digital reconstruction to enable detailed study.

Evans said, "This specimen has been referred to many times in scientific papers, but it had yet to be successfully identified—we were not even sure whether it was dinosaur. It was named Zanclodon cambrensis by Edwin Tully Newton in 1899, but we knew the name Zanclodon had been abandoned as referring to a broad variety of early reptiles. Therefore, we name it after Newton, calling it Newtonsaurus. It is different from all other dinosaurs from around that time, and requires a distinctive name."

Professor Michael J Benton, who is the senior author on the paper, said, "The natural molds of the inner and outer faces of the jawbone show amazing detail—every groove, ridge, tooth, and even the serrations along the edges of the teeth. We decided to use digital photography to make a 3D model.

"We began by surface scanning the fossil using photogrammetry. Once we had our digital scan, we then inverted it—essentially giving us a digital negative of the mold. It was then a simple case of fusing the two sides together and analyzing the anatomy from there. The digital reconstruction we have extracted from the specimen gives a much better idea of what the original structure of the bone would have looked like."

Now that the fossil could be studied, the team was able to use its anatomy to piece together its position in the reptile family tree—and most crucially—whether it was a dinosaur or not.

Evans said, "We can now confirm that this specimen very likely belonged to a large predatory theropod dinosaur, that roamed the shores of South Wales during the latest Triassic. It has some definite unique dinosaur features in the emplacement of the teeth, and it is a theropod—a predatory, flesh-eating dinosaur. Otherwise, it sits near the origins of both major divisions of Theropoda, the Coelophysoidea and the Averostra.

"Most unexpected is the size of the animal. The preserved jawbone is 28 cm long, and that is just the front half, so originally the jawbone was 60 cm long, corresponding to a dinosaur with a body length of 5–7 meters. This is unusually large for a Triassic theropod, most of which were half the size or smaller."

Cindy Howells at the National Museum of Wales said, "These historical specimens are vitally important in paleontology and often yield new and exciting results—even if they have been sitting in collections for years. The Victorians were fascinated by the fossil record and prospected all across the U.K. for fossils.

"On top of this, the re-description of Newtonsaurus cambrensis once again highlights the significance of Wales in paleontological research. These Triassic beds are rare worldwide, and yet there are several across Wales. There might very well be another dinosaur waiting to be discovered."