Sea turtle fossils unearthed in Alabama come from a never before seen species that dates back to the Late Cretaceous epoch, according to new research published in the journal PLOS ONE.
Scientists have long believed that modern day sea turtles all come from one ancestor of the Peritresius clade that lived during the Late Cretaceous epoch some 100 million to 66 million years ago. The species — Peritresius ornatus — mainly lived in northern regions. However, a few fossils have also been discovered in the southeastern United States.
In the study, a group of scientists at the University of Alabama analyzed such remains and found that some came from a never before seen Peritresius species known as Peritresius martini. They made that discovery by looking at specific anatomical features, such as the shape of the turtle’s shell and different skin elements, and comparing them across species.
The features suggest that P. ornatus was capable of thermoregulation, a trait that would have allowed them to keep warm during the cooler periods of the Cretaceous when many other turtle species died off. However, that is all researchers know about the turtles for now.
“Without a skull or any of the rest of the skeleton, we don’t really know much about how this species would have moved, what it ate or how it lived,” said study co-author Andrew Gentry, a researcher from the University of Alabama, in a statement. “The only way to answer these questions is by finding more complete specimens.”
This information sheds light on a new species and gives more insight into the evolutionary path of modern sea turtles. In addition, it also suggests the reptiles may have been more widespread than previously thought.
“This discovery not only answers several important questions about the distribution and diversity of sea turtles during this period but also provides further evidence that Alabama is one of the best places in the world to study some of the earliest ancestors of modern sea turtles,” added Gentry, according to Phys.org.