A team of scientists led by curator of the South Carolina State Museum, David Cicimurri announced Thursday the discovery of two new fossil shark species from the southeastern United States.
Cicimurri was joined by Jun Ebersole, Director of Collections at the McWane Science Center in Birmingham, AL and George Martin, retired USDA soil scientist from Auburn, AL. The species date from the Paleogene Period, which was approximately 65 and 35 million years ago. The fossils were named based on hundreds of isolated teeth that were discovered in south Alabama and central Georgia.
The two new species are members of the same genus, Mennerotodus, a group of extinct sharks that were known previously from only Europe and Asia. The older species, Mennerotodus mackayi, was discovered in Alabama and lived during the Paleocene Epoch.
“This new species appeared just after the extinction of the dinosaurs, and based on the number of teeth we recovered, it was likely one of the more common species in the ancient Gulf of Mexico 65 million years ago,” Ebersole said.
The second shark, Mennerotodus parmleyi, lived during the Eocene Epoch, roughly 35 million years ago. Cicimurri said this shark was named from hundreds of teeth recovered from a defunct kaolinite mine in central Georgia.
“These teeth were originally identified as two or three different species,” said Cicimurri. “Our reanalysis of the teeth showed they instead belonged to an entirely new species.” The new species was named for Dr. Dennis Parmley, a retired professor at Georgia College and State University, in honor of his contributions to the study of fossils in Georgia.
Before naming the two new species, the team of scientists spent months reconstructing the dentitions of the sharks using hundreds of isolated teeth and by comparing them to modern species. “By piecing together and examining the dentitions of these new shark species, we were able to determine that they are closely related to modern Sandtiger Sharks, so close in fact, that we were able to use modern Sandtiger jaws to reconstruct them,” Cicimurri said.
After examining additional teeth from various museum collectors, the team was able to conclude that Mennerotodus teeth are relatively common in the southeastern U.S.
The team’s study was published in the open access journal Fossil Record and is available to download online.