New Historical Shark Species Found Hidden in World’s Largest Cave System

A beforehand unknown species of historical shark has been found in Kentucky’s Mammoth Cave Nationwide Park, dwelling to the world’s longest cave system.

The system, which is positioned within the state’s south-central area, extends for greater than 400 miles and encompasses a collection of enormous underground passages. The system’s rocks date to the Mississippian interval (359 to 323 million years in the past), across the time that the supercontinent Pangea was forming. For a lot of this era, the stretch of land that’s now Kentucky, then positioned south of the equator, was lined by shallow tropical seas.

The distinctive surroundings throughout the Mammoth Cave system has resulted within the extraordinary preservation of historical shark fossils. So far, greater than 100 species of historical cartilaginous fishes—a bunch that features sharks, rays and skates—have been recognized there.

An illustration reveals the newly found historical shark species Strigilodus tollesonae. The creature is a form of petalodont—an extinct group of marine cartilaginous fish present in what’s now the USA and Europe.
Benji Paysnoe / NPS

The Mississippian rocks that kind the Mammoth Cave system are divided into a number of layers known as, from oldest to youngest, the St. Louis Formation, St. Genevieve Formation, the Girkin Formation and Huge Clifty Sandstone. The older St. Louis and St. Genevieve formations include the best variety of historical sharks.

Researchers recognized the traditional shark species after discovering a number of small, spoon-like enamel in a cave wall, the Nationwide Park Service (NPS) mentioned Wednesday, which was Nationwide Fossil Day.

The enamel had been uncovered throughout an ongoing analysis undertaking referred to as a paleontological sources stock (PRI) that’s being coordinated by officers from the Mammoth Cave park and the NPS Paleontology Program.

Scientists have named the brand new shark species Strigilodus tollesonae. The creature is a form of petalodont (“petal-toothed”), an extinct group of cartilaginous marine fish present in what’s now the USA and Europe.

An NPS spokesperson informed Newsweek, “The enamel of Strigilodus tollesonae had been found throughout the St. Genevieve Formation rock layer at Mammoth Cave Nationwide Park. This might place it as dwelling roughly 340 to 320 million years in the past.”

In a press launch, Barclay Trimble, the park’s superintendent, mentioned, “We’re excited to lastly announce the invention of our first new shark species at Mammoth Cave on Nationwide Fossil Day.”

He went on: “Groups of geologists, paleontologists, park workers, and volunteers have been arduous at work deep contained in the cave figuring out and amassing fossils because the paleontological sources stock started in 2019. Their vital analysis permits us to higher perceive the scope, significance, distribution, and administration points related to the fossil document discovered inside Mammoth Cave.”

Strigilodus tollesonae is extra carefully associated to trendy ratfish than different present-day sharks and rays, based on researchers.

The enamel of this shark which were discovered to this point characterize all attainable tooth positions within the mouths of each adults and juveniles of this species. It seems that the enamel had been organized in a fan-like construction. The traits of the fossils point out that the shark could have lived like trendy skates, feeding on snails, bivalves, soft-bodied worms and smaller fish.

The shark’s title interprets to “Tolleson’s scraper tooth” in Latin. The species was named in honor of Mammoth Cave information Kelli Tolleson, who performed a major position within the PRI.

Tolleson uncovered a number of vital fossil websites within the Mammoth Cave park, lots of that are troublesome to entry. Generally researchers should crawl for lengthy distances by way of small openings to achieve them.

Replace 10/13/23, 1:29 p.m. ET: This text was up to date with remark from the Nationwide Park Service.