A newly identified ancient shark species, Macadens olsoni, has been at Mammoth Cave National Park. The National Park Service says Macadens olsoni likely measured less than a foot long and featured a distinctive row of curved or spiral teeth.

It's Shark Week, and Mammoth Cave took the unofficial holiday to announce the discovery of a ancient shark species.

National Park Service researchers have identified a previously unknown shark species in the limestone walls of Mammoth Cave, the world’s longest known cave system. The animal, named Macadens olsoni, measured less than one foot long and swam the warm, shallow waters that covered this region roughly 340 million years ago.

“ Macadens olsoni is notable for its unique tooth whorl, a curved row of teeth designed for crushing small sea creatures. This ancient shark likely grew to less than a foot in length and probably feasted on mollusks and worms,” rangers said in the release.

A new species of ancient shark has been discovered at Mammoth Cave National Park in Kentucky, officials said.

MAMMOTH CAVE, Ky. — A new-to-science species of ancient shark was recently discovered in Mammoth Cave National Park in Kentucky. The Macadens olsoni is known for its unique tooth whorl, a curved row of teeth designed for crushing small sea creatures.

Scientists have identified a new 335-million-year-old shark species, Macadens olsoni, under Mammoth Cave National Park—one of over 40 ancient shark finds that illuminate early marine life and the park’s paleontological importance.

A new species of ancient shark has been discovered in Kentucky in the United States, according to researchers. The species was identified from a fossil at Mammoth Cave National Park, which is home to other re-SHARK-able discoveries.