Paleontologists Discover a New Pterosaur, Filling a Key Gap on the Evolutionary Timeline for These Flying Reptiles

During the Jurassic period, sharp-toothed flying reptiles with the wingspan of a modern golden eagle soared through the skies, before being wiped out by the same meteor that decimated the dinosaurs.

Called Skiphosoura bavarica, the new pterosaur species was identified after scientists discovered a surprisingly well-preserved fossil in southeast Germany in 2015. Now, in a study published in Current Biology, an international team of experts reveals how Skiphosoura fills an important gap in pterosaur evolution that paleontologists have been puzzling over for the better part of 200 years.

“This is an incredible find. It really helps us piece together how these amazing flying animals lived and evolved,” lead author David Hone, a paleontologist at Queen Mary University of London, says in a statement. “Hopefully, this study will be the basis for more work in the future on this important evolutionary transition.”

Pterosaurs were the first and largest vertebrates to develop powered flight. They are not dinosaurs, but they coexisted with the iconic reptiles from the Triassic period to the end of the Cretaceous.

For most of the past two centuries, scientists were aware of two major groups on the pterosaur evolutionary timeline. On the oldest end, there were the non-pterodactyloids, which had a short head, short neck, short bone in the wrist of the wing, a long fifth toe and a long tail.

Later, the much larger pterodactyloids evolved, with a large head, long neck, long wrist bone, a short fifth toe and a short tail—essentially the opposite of the non-pterodactyloids. Their wingspans could reach up to around 33 feet in length—and in the words of IFL’s Stephen Luntz, pterodactyloids were “the largest flying creatures until airplanes became big enough to transport elephants.”

How the smaller, early pterosaurs evolved into giant pterodactyloids remained a mystery. Which of their several anatomical changes happened first, and which ones followed? Scientists weren’t sure—but the discovery of intermediate species called darwinopterans, first uncovered in China in 2009, provided an important clue. Darwinopterans demonstrated that the head and neck of pterosaurs changed first.

Then, the complete Skiphosoura specimen came along in 2015, thrilling scientists with its impressive conservation of nearly every single bone in three dimensions, instead of the more flattened remains typical of pterosaurs. Derived from ancient Greek, Skiphosoura bavarica means “sword tail from Bavaria,” referring to the German region where it was found. Its name was inspired by the species’ short, stiff and pointed tail. It also had sharp teeth and a crest on the front of its head.

“It would have been a generalized predator of small prey, taking things like lizards, small mammals, big insects and maybe fish. It was probably living inland, perhaps in forests,” Hone tells Reuters’ Will Dunham. He adds that the creature might have also displayed bright colors or patterns.

On the pterosaur timeline, Skiphosoura existed between the darwinopterans and the giant pterodactyloids, toward the end of the Jurassic Period. Skiphosoura had a wingspan of about six feet and, like the earlier darwinopterans, it showcased a pterodactyloid-like head and neck. But it also had a longer wrist and shorter toe and tail than its predecessors—evidence of the evolution toward pterodactyloids.

In other words, thanks to Skiphosoura, the scientists were able to shed further light on the evolutionary changes that took place between early pterosaurs and later pterodactyloids. It “also brings other pterosaur finds we had already made into focus, better explaining where they go in the family tree of pterosaurs and allowing us to show this transition from the early to late forms—and see what features were changing in what order,” Hone tells Reuters.

In fact, the study also places Dearc, a Scottish pterosaur also from the Jurassic, earlier than Skiphosoura on the new timeline. By putting these groups in chronological order, researchers can trace how their anatomy changed: from the non-pterodactyloids to Dearc, the first darwinopterans, Skiphosoura and finally the pterodactyloids.

“With both Skiphosoura and Dearc now fitting into the pterosaur evolutionary order, artists could draw a gap-free version of “The March of Progress”—but for flying lizards,” writes Paul Smaglik for Discover magazine.

Margherita Bassi | READ MORE

Margherita Bassi is a freelance journalist and trilingual storyteller. Her work has appeared in publications including BBC Travel, Discover magazine, Live Science, Atlas Obscura and Hidden Compass.