The new species of ‘dragon chief’ dinosaur was actually the size of a chicken.

An illustration of the new description Pendraig milnerae, the oldest known carnivorous dinosaur in the UK. Next to it are three lizard-like reptiles, known scientifically as the Clevosaurus cambrica. (Image credit: James Robbins)

Hail to the ‘dragon chief’: The oldest carnivorous dinosaur ever discovered in the UK may seem monstrous, but the clawed predator was in fact a pip-squeak, according to a new study.

The size of the chicken dinosaur lived in what is now Wales between 215 and 200 million years ago, in the late Triassic period. It was probably a top predator, despite its small size, the researchers found, so they named it Pendraig milnerae. Its genus name means “chief dragon” in Middle Welsh, a reference to the medieval Welsh term “chief warrior”, and its species name pays homage to Angela Milner, a paleontologist at the Natural History Museum in London who helped locate fossils of the species in the museum’s collections before his death in August.

Pendraig milnerae lived near the beginning of the evolution of carnivorous dinosaurs, “the study’s first author, Stephan Spiekman, a researcher at the Natural History Museum specializing in the evolution of Triassic reptiles, said in a statement.” It is clear from the bones. that we have that he was a meat eater, but at the start of the evolution of this group, these animals were quite small, unlike the very famous carnivorous dinosaurs like T. rex, which evolved much later. “

Related: Photos: the new dinosaur had small arms, just like the T. rex

The researchers described P. milnerae from an incomplete specimen, as well as two additional fragmentary specimens, found in a quarry in Pant-y-ffynnon, a village in south Wales. The remains of the dinosaur indicate that it was about three feet long, including its tail, and that it was a theropod, a group of bipedal, mainly carnivorous dinosaurs.

“This is an exciting discovery of a new species of theropod from the dawn of the dinosaurs (Upper Triassic), an era that has yielded less than a handful of these species across Europe (and the UK’s first). Uni), “said Darla Zelenitsky, an associate professor of paleobiology at the University of Calgary in Alberta who was not involved in the study, told Live Science in an email. “It would have looked something like the small and seemingly cute (but notorious) Compsognathus of the film ‘[The Lost World:] Jurassic Park. ‘”

Although researchers discovered the chef’s fossils decades ago, he has not been identified as a new species until now. When the study’s lead author, Susannah Maidment, a senior palaeobiology researcher at the Natural History Museum, decided to re-examine her bizarre remains, she told Milner she couldn’t find the specimen, Maidment said. in the press release. “And so she [Milner] left, and about three hours later she had it, “Maidment said.” This document wouldn’t have been possible without her. “

Milner was a theropod scholar who helped describe the “heavy-clawed” spinosaurid dinosaur. Baryonyx walkeri in the 1980s, and she also studied brain anatomy Archeopteryx, the oldest known avian dinosaur. “I’m also happy to see this [new] dinosaur was named after Dr. Angela Milner, who did research on dinosaurs at a time when few women did, ”Zelenitsky said.

Various fossilized bones of the “dragon chief” dinosaur Pendraig milnerae, including different views of her pelvis and vertebrae (left) and left femur (right). (Image credit: Spiekman SNF, et al. R. Soc. Open Sci. (2021))

Dwarf dinosaur?

The chief dragon’s small size may be a result of its surroundings, the researchers said.

“The area where these specimens were found was most likely an island when they lived,” Spiekman said. “Species that live on islands often tend to become smaller than those on the mainland in a phenomenon called island dwarfism.”

To study this idea, Spiekman and colleagues used statistical analyzes to compare the size of P. milnerae along with other theropods and primitive coelophysoids, a group of the theropod family which P. milnerae belonged to. But while some theropods evolved to become larger in the Triassic, coelophysoids remained “considerably smaller,” the researchers wrote in the study.

“The results indicate that Pendraig [milnerae] is indeed small, even for a theropod of this period, but not exclusively, ”Spiekman said.

In addition, it seems that the fossils in the museum of P. milnerae may not be from fully mature individuals. “So Pendraig might have grown a bit larger than the specimens we have so far, limiting our ability to perform reliable body size analyzes, ”Spiekman said.

In other words, researchers will need to find more fossils of this or other possible Triassic dwarf dinosaur species in Wales to see if island dwarfism has occurred there. “If we could prove it, this would be the first known occurrence of this evolutionary phenomenon,” Spiekman said.

But even though P. milnerae was not a dwarf, the find is still a big deal for the region. “Dinosaur finds are really rare in Wales, and it is only the third known dinosaur species in the country,” said study co-researcher Richard Butler, professor of paleobiology at the University. from Birmingham in the UK, in the press release.

The study was published online Wednesday (October 6) in the journal Royal Society Open Science.

Originally posted on Live Science.

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