Fossilized ‘Chipmunk Shark’ teeth discovered in Mammoth Cave rock layer

MAMMOTH CAVE, Ky. (FOX 56) — A new species of ancient shark was recently discovered at Mammoth Cave National Park.

Fossilized teeth of the “McGinnis Nail Tooth,” nicknamed the “Chipmunk Shark” due to its small, chisel-like front teeth, was found inside of a rock layer inside the Kentucky cave system, per the National Park Service.

“The fossil discoveries in Mammoth Cave continue to reveal a wealth of new information about ancient shark species,” said Superintendent Barclay Trimble. “Researchers and volunteers collected samples from the main Mammoth Cave system and from smaller isolated caves throughout the park that have provided new data on previously known ancient sharks and revealed several species that are brand new to science. These discoveries help scientists to better understand the relationship and evolution of modern shark species within this relatively small geographic region.”

According to a news release, NPS officials believe the Chipmunk Shark foraged on crustaceans, worms, and other small animals along the ocean floor.

The Ste. Genevieve Formation at Mammoth Cave, where the fossilized teeth were found, is a roughly 340-million-year-old layer of rocks, NPS announced. Over the last several years, more than 70 species of sharks and other fish have been identified in the rock layer, including four new species.

NPS officials said that before these discoveries, there were no known shark fossils in the rock layer.

The Chipmunk Shark was believed to have swam along the ocean floor that is said to have covered much of central Kentucky during the Middle Mississippian period, officials claim.