The tuatara, Sphenodon punctatus, has often been called a ‘living fossil’ because it is the sole species of its lineage, having been separate from the squamates (lizards and snakes) since the Triassic. Indeed, diverse Mesozoic sphenodontians show the group was once much more diverse and successful than it now is.
Now, MSc student Grace Kinney-Broderick is a co-author on a paper in Scientific Reports about about a new sphenodontian from the Early Jurassic of Arizona, USA, called Navajosphenodon sani. The new fossil is represented by a nearly complete articulated skeleton and dozens of upper and lower jaws, spanning a range of developmental stages. Phylogenetically it sits right beside the modern Sphenodon, close to the Early Jurassic Cynosphenodon from Mexico, indicating a lineage that has remained anatomically almost unchanged for nearly 200 million years.
The work was conducted at Harvard University with Dr. Stephanie Pierce and Dr. Tiago Simões. Grace was completing her undergraduate BSc at Boston College during this time by working in collaboration with the Museum of Comparative Zoology. Grace comments, “I am a co-author on my first publication! I am beyond excited and so thankful to Dr. Pierce and Dr. Simões for the opportunity.”
[Right] Grace and the title page of her paper.