Europe’s missing ceratopsian dinosaurs have finally been found

Relatives of Triceratops have never been found in Europe – until now.

Since the first dinosaur was named over 200 years ago, only four potential ceratopsians have been unearthed in the whole of Europe. However, the fragmentary nature of these fossils meant that their true identity has been contentious.

Instead, scientists thought that Europe was dominated by a group of little-known dinosaurs called the rhabdodontids. These animals, which are relatives of Iguanodon, are found nowhere else on Earth.

New research, published in the journal Nature, now explains why. After studying an 84-million-year-old dinosaur called Ajkaceratops, palaeontologists have realised that many rhabdodontids might actually be misidentified ceratopsians.

These dinosaurs would have lived in Europe when the continent was a series of islands dotted around the Tethys Sea, which could help to explain their unique diversity. Professor Susannah Maidment, our dinosaur expert who led the paper, says that the finding rewrites what palaeontologists know about Cretaceous Europe.

“This paper shows that, rather than being completely absent, ceratopsians were actually quite common in Europe,” Susannah adds. “It means that the European dinosaur faunas probably weren’t that different from other parts of the northern hemisphere.”

“In this case, the idea that Europe’s islands drove the evolution of many unique species might not be as strong as was once thought. That makes it even more important to re-examine Europe’s dinosaur fossils to find out what was happening here in the Late Cretaceous.”

How did ceratopsians evolve and spread around the world?

By confirming the existence of ceratopsians in Europe, the study fills in a long-standing gap in the journey these dinosaurs took across the northern hemisphere.

The earliest ceratopsians, such as Yinlong, evolved in Asia before dispersing multiple times into North America. Here, they evolved into large, frilled species such as Triceratops and Torosaurus. The easiest route for these dinosaurs to have taken would have been through Europe, but the historic lack of fossils from this region challenged that narrative.

“We know that dinosaurs were able to cross the Atlantic, which was just starting to open during the Cretaceous,” Susannah explains. “Dinosaurs such as Allosaurus have been found in Portugal and the USA, showing that they had at least some ability to move between continents.”

“Lots of animals can swim and, as the islands of the central European basin weren’t that far apart, it would make sense if dinosaurs were able to island hop. It would be much stranger if they couldn’t.”

The discovery of new Ajkaceratops skull fossils has finally provided the evidence that shows ceratopsians did make it to Europe after all. The palaeontologists found that not only was this Hungarian dinosaur definitely a ceratopsian, but that a closely related rhabdodontid called Mochlodon was actually the same species.

As they pulled further on this thread, they found that the science behind all rhabdodontids began to unravel.

Reinventing the rhabdodontids

After realising that rhabdodontids such as Mocholodon might just be ceratopsians who adapted to life on European islands, the team started looking at other rhabdodontid dinosaurs from the continent.

Their analyses showed that the Romanian dinosaur Zalmoxes shqiperorum, often depicted as a miniature Iguanodon-like animal, was also a ceratopsian. Its pelvis, for example, lacks a protuberance that iguanodontians have.

The researchers moved the species to the new ceratopsian genus Ferenceratops, named in honour of Baron Franz Nopcsa, a famous Austro-Hungarian palaeontologist of the twentieth century who originally found its remains.

The team’s findings were less certain about another Zalmoxes species, Z. robustus, whose name remains unchanged. This is because it appeared as both a ceratopsian and an iguanodontian depending on how the data was analysed.

Susannah says that this highlights the difficulty in studying two groups of closely related dinosaurs, especially when their European remains are often not well preserved.

“While Iguanodon and Triceratops look very different, the groups they are part of evolved from a common ancestor, meaning they’ve both inherited certain characteristics,” explains Susannah. “They also independently evolved four-leggedness, complex chewing mechanisms and a large body size.”

“This means that their teeth and limbs look quite similar, both because of their shared history and way of life. So, when we only have small parts of the skeleton to look at, it can be quite difficult to tell what’s what.”

It will hopefully become easier to study these animals in the future as the dust settles following the paper’s seismic shift in dinosaur taxonomy. Susannah hopes that it will spur palaeontologists to revisit existing dinosaur species and re-examine what they think they know.

“Had Nopcsa’s material been found today, I don’t think it would have been interpreted as iguanodontian because of what we now know about these dinosaurs,” Susannah says. “So, we can’t assume that the identity of a species is correct just because it’s already been studied.”

“This demonstrates how museum collections are not just storage: they are a living archive that needs constant updating. By reinterpreting what we have, and finding more complete skeletons, we’ll be able to better understand the lives of these dinosaurs.”