The fanged jaws of the largest Jurassic pterosaur known to science was spotted by PhD student Amelia Penny poking out of a rock on the Isle of Skye, Scotland, back in 2017. After battling the tides to retrieve the phenomenal fossil with diamond-tipped saws, the team behind the discovery has been studying it at the University of Edinburgh.

The fearsome, fanged, and winged specimen is now described in a paper in the journal Current Biology, describing both the magnificence of the fossil preserved in three dimensions and the significance of this new species in our understanding of Jurassic pterosaurs.

The name of the new species, Dearc sgiathanach (pronounced jark ski-an-ach), is Scottish Gaelic and pays homage to the Isle of Skye where it was found, with the double meaning of “winged reptile” and “reptile from Skye”.

As the largest pterosaur of the Jurassic period known to science, it’s expected to have had a wingspan over 2.5 meters (over eight feet).

Incredibly, even at this vast size, it seems D. sgiathanach wasn’t done yet. A peek at the growth rings inside its bones revealed that it was a juvenile-subadult and not yet fully grown when it died.

A toothy predator, D. sgiathanach would’ve spent its day scooping large fishes and squid out of the warm waters of Scotland, which at that time was closer in climate to the Canary Islands. This lifestyle of snatching animals from the water is demonstrated in its enormous teeth that would’ve easily pierced and held onto prey.

What D. sgiathanach can tell us about pterosaurs in a broader sense is that these flying reptiles were reaching large sizes earlier than previously expected. It had been previously considered that they spent the Triassic through to the Jurassic quite restricted in size before supersizing in the Cretaceous alongside a diverse range of birds. 

However, it now seems that this plateau in size through to the Cretaceous is an inaccurate theory, and that actually significant evolution was occurring among the pterosaurs as far back as the Middle Jurassic.

“There were fairly large pterosaurs in the Jurassic (wingspans > 1.8 m), but reasonably complete adult or near-mature skeletons are mostly lacking, for reasons unclear and worthy of further study,” wrote the study authors. “The Middle Jurassic age of Dearc adds to increasing evidence that this interval—once a frustrating gap in the pterosaur record—was in fact a dynamic time of diversification.”

“As with dinosaurs and mammals, the Middle Jurassic was likely a vibrant time in pterosaur history, not a static and archaic prelude to a Cretaceous explosion of larger, more disparate, more efficient fliers.”