Thursday, September 11, 2025

New dinosaur from Wales identified in museum drawer

Paleontologists shed new light on specimen more than 125 years after it was discovered

University of Bristol

Newtonsaurus fossil jawbone specimen — image:
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
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Credit: Owain Evans

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

Owain Evans said: “This specimen has been referred to many times in scientific papers, but 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 moulds 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 mould. It was then a simple case of fusing the two sides together and analysing 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.

Owain 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 metres. 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 palaeontology 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 UK for fossils. On top of this, the re-description of Newtonsaurus cambrensis once again highlights the significance of Wales in palaeontological 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.”

Paper

‘Re-assessment of a large theropod dinosaur dentary from the Rhaetian of South Wales’ by Owain Evans, Cindy Howells, Nathan Wintle, and Michael Benton, in Proceedings of the Geologists’ Association.

Journal

Proceedings of the Geologists Association

DOI

10.1016/j.pgeola.2025.101142

Article Title

Re-assessment of a large archosaur dentary from the Late Triassic of South Wales, United Kingdom

Article Publication Date

11-Sep-2025

Newly dated 85-million-year-old dino eggs could improve understanding of Cretaceous climate

Scientists date dinosaur eggs that had laid buried in rock for millions of years for the first time, using new, ‘atomic clock for fossils’ method

Frontiers

image:
Egg clutch sampled for chronological studies. Credit Dr. Bi Zhao
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Credit: Dr. Bi Zhao

In the Cretaceous period, Earth was plagued by widespread volcanic activity, oceanic oxygen depletion events, and mass extinctions. Fossils from that era remain and continue to give scientists clues as to what the climate may have looked like in different regions.

Now, researchers in China have examined some of them: dinosaur eggs found at the Qinglongshan site in the Yunyang Basin in central China. This is the first time that dinosaur eggs have been dated using carbonate uranium-lead (U-Pb) dating. The team published their results in Frontiers in Earth Science.

“We show that these dinosaur eggs were deposited roughly 85 million years ago, in the Late Cretaceous period,” said corresponding author Dr Bi Zhao, a researcher at the Hubei Institute of Geosciences. “We provide the first robust chronological constraints for these fossils, resolving long-standing uncertainties about their age.”

New dates

Qinglongshan is China’s first national dinosaur egg fossil reserve. There, more than 3,000 fossilized eggs are spread across three sites. Most fossils are embedded in different stones, such as breccias, breccia and siltstone mixes, and fine sandstones. The eggs have mostly remained in their original location and show only minimal deformation. The majority is thought to belong to a single species, Placoolithus tumiaolingensis, which belongs to the family Dendroolithidae, a group characterized by highly porous eggshells. The sampled calcite-filled dinosaur egg fossil came from a cluster of 28 eggs embedded within breccia-bearing siltstone.

To date the egg, the team used U-Pb dating. “We fired a micro-laser at eggshell samples, vaporizing carbonate minerals into aerosol. This is analyzed by a mass spectrometer to count uranium and lead atoms. Since uranium decays into lead at a fixed rate, we were able to calculate the age by measuring accumulated lead— it’s like an atomic clock for fossils,” Zhao explained.

The results showed that the eggs from this cluster were deposited around 85 million years ago, with the possibility of them having been deposited around 1.7 million years earlier or later. Their age means they’ve been laid during the Late Cretaceous, an epoch lasting from approximately 100 to 66 million years ago. They are the first reliably dated fossils from the Qinglongshan site.

Traditionally, dating dinosaur eggs involves indirect methods, such as dating volcanic rock, ash layers, or minerals around eggs. These, however, may have formed before or after the laying of the eggs, or geological processes may have altered them. The method used here allows for precise dating of eggs without having to rely on anything but the eggs themselves. “It revolutionizes our ability to establish global dinosaur egg chronologies,” Zhao said.

Old climates

Global cooling had started several million years before the laying of the eggs, in the Turonian epoch (lasting from approximately 93.9 to 89.8 million years ago). By the time they were laid, temperatures had declined significantly. The transition from a warm to a cooler climate was likely a factor in dinosaurs’ diminishing diversity and may have affected how many eggs were laid by how many species at Qinglongshan. “Dendroolithids’ specialized pore structures may represent evolutionary adaptations to this climatic shift, as novel egg types emerged worldwide during cooling,” Zhao said. The pore structure of Dendroolithidae eggs, which are markedly different from many other dinosaur eggs, may be one such adaptation. “P. tumiaolingensis may represent an evolutionary dead end where the egg-laying dinosaur population failed to adapt successfully to cooling climates,” Zhao explained.

Although few eggshell samples were examined in this study, all tests confirmed similar ages of egg fragments, which were also consistent with the age of the rocks surrounding the eggs. The team will be expanding sampling to include eggs found in different rock layers, which could help construct a regional timeline. They also said that Dendroolithid eggs in neighboring basins should be examined in the future to trace dinosaur migrations.

“Our achievement holds significant implications for research on dinosaur evolution and extinction, as well as environmental changes on Earth during the Late Cretaceous,” Zhao said. “Such findings can transform fossils into compelling narratives about Earth’s history.”