Scientists uncover fossil of 247-million-year-old reptile with unique skin crest
A previously unknown reptile species with a striking skin crest has been identified by Dutch paleontologist Stephan Spiekman and an international research team. The reptile, named Mirasaura, lived 247 million years ago in what is now northern France, during the Triassic period, shortly after a mass extinction event reshaped life on Earth, NOS reports.
The fossil, which includes a skull, a nearly complete body, and fragments of the crest, had been stored for decades in the collection of the State Museum of Natural History in Stuttgart, Germany. Originally excavated from quarries in Lorraine in the 1930s by a fossil collector, the bones were not thoroughly studied until the museum received them in 2019.
Spiekman, who is based at the Stuttgart museum, used advanced imaging technology to examine the fossils. A CT scan of the skull was performed at a particle accelerator in Grenoble, France, and additional research was conducted into the pigment structures—or “color granules”—within the crest.
The most unusual feature of Mirasaura is its dorsal crest, which appears to be made of a new type of skin structure that resembles feathers but is neither feather, scale, nor hair. “This really changes how we need to look at reptiles,” Spiekman told NOS. The crest likely served a signaling function, possibly to deter predators or communicate with other Mirasaura individuals. It was not suited for gliding or temperature regulation.
According to the study, this type of skin growth developed independently from feathers and fur in the evolutionary timeline. Evolutionary biologist Richard Prum of Yale University, in a commentary published alongside the research in Nature, wrote, “The evolutionary possibilities of reptile skin are far stranger than previously thought.”
Dennis Voeten, curator at Natuurmuseum Fryslân, emphasized the ancient origins of such structures. “The capacity to form these features is older than we assumed,” he told NOS. While feathers evolved from reptilian skin and later gave rise to birds, Mirasaura belongs to a reptile lineage that diverged much earlier, making it only distantly related to both dinosaurs and modern reptiles.
Spiekman explained that the period in which Mirasaura lived was one of evolutionary experimentation. The Triassic followed a mass extinction event likely triggered by extensive volcanic activity. “The world was fairly empty,” he told NOS. “A great number of new animal and plant species evolved to fill the space that had opened up. Reptiles especially took full advantage of it.”
Modern reptile groups such as turtles, lizards, and crocodiles emerged during that time, along with many now-extinct lineages, including Mirasaura. That lineage likely disappeared around 200 million years ago, well before the rise of the dinosaurs in the Jurassic and Cretaceous periods.
Skin outgrowths such as feathers, hairs, and scales are considered key evolutionary innovations. “Mammals wouldn’t exist without the evolution of hair,” Spiekman told NOS. “Hair allowed us to cover our bodies and maintain a constant temperature.”
The genetic foundation for producing these skin structures is ancient. Over evolutionary time, the same genes have led to different forms of outgrowths—such as feathers, scales, or, as now demonstrated, Mirasaura’s “alternative feather.”
