New fossil discovery reveals key step in the evolution of flying reptiles

Life restoration of two Skiphosoura bavarica in flight. Credit by: Gabriel Ugueto.

The new species, named Skiphosoura bavarica, was identified by a team led by Dr David Hone, a palaeontologist from Queen Mary University of London. Their findings were published today in the journal Current Biology.

The pterosaurs, close relatives of dinosaurs, were the first vertebrates to achieve powered flight. While early species typically had wingspans of about 2 metres, later pterosaurs evolved into enormous forms with wingspans reaching 10 metres. The discovery of Skiphosoura bavarica provides critical insights into how these transformations occurred.

Hailing from southern Germany, Skiphosoura boasts a rare, nearly complete skeleton preserved in three dimensions—a significant contrast to the often-flattened fossils of its relatives. Measuring about 2 metres in wingspan, the new species’ most striking feature is its short, stiff, sword-like tail, which inspired its name: “sword tail from Bavaria.”

“This is an incredible find,” said Dr Hone. “It really helps us piece together how these amazing flying animals lived and evolved. Hopefully, this study will inspire more research into this important evolutionary transition.”

For two centuries, scientists divided pterosaurs into two major groups: early non-pterodactyloids, characterised by short heads, long tails, and specific wing and toe structures, and the later pterodactyloids, which had larger heads, shorter tails, and other adaptations for efficient flight. Intermediate species, like the Darwinopterus discovered in the 2010s, showed how the head and neck evolved first.

Skiphosoura represents a critical step beyond the Darwinopterus. Its head and neck resemble the more advanced pterodactyloids, while its wrist, tail, and foot show transitional features. These traits help trace the gradual adaptations that allowed later pterosaurs to grow to massive sizes.

The study also reconstructed the evolutionary family tree of pterosaurs, placing Skiphosoura between Darwinopterus and true pterodactyloids. Additionally, a Scottish pterosaur named Dearc was identified as a key intermediate between early pterosaurs and Darwinopterus. Together, these findings form a near-complete evolutionary sequence for pterosaurs, detailing how their anatomy changed over time.

The discovery was made possible through the efforts of an international team. Adam Fitch, from the University of Wisconsin-Madison, highlighted the significance of Skiphosoura: “Pterosaurs have long been symbols of the unique life of the past. Skiphosoura represents an important new form for working out pterosaur evolutionary relationships and how this lineage arose and changed."

The specimen was prepared by Stefan Selzer, who remarked: “Having worked on over 60 pterosaurs from the Solnhofen limestone, it became clear during preparation that this fossil displayed features from both major groups of pterosaurs, with the shortened tail being a crucial diagnostic trait.”

Bruce and René Lauer of the Lauer Foundation, who contributed to the project, underscored the importance of modern techniques such as UV photography in uncovering fine details of the specimen. “We are proud to bring this important specimen to science and further the understanding of pterosaur evolution,” said Bruce Lauer.

With its blend of cutting-edge research, meticulous preparation, and international collaboration, the study of Skiphosoura bavarica offers a significant leap forward in understanding the evolutionary journey of these extraordinary flying reptiles.