Opening details

These sharks probably lived in an ancient sea that existed before the formation of the supercontinent Pangea. Two new species, Troglocladodus trimblei and Glikmanius careforum, were detected. Both are ctenacanths, ancient relatives of modern sharks with protective comb-like spines on their spines.

Fossils from Mammoth Cave are generally much better preserved because they have not been exposed to the elements, and yet they retain much more detail than fossils found on the surface. Scientists found particularly well-preserved teeth: “In such a stable environment, they look like they came out of a shark’s mouth just yesterday.”– said paleontologist John-Paul Hodnett.

• The species is believed to be T. trimblei It reached a length of about 3-3.6 meters. It had fork-like teeth, giving rise to the name Troglocladodus, meaning “cave-branched tooth”. The species name trimblei is in honor of Mammoth Cave manager Barclay Trimble, who found the first specimen in 2019.
• G.careforum It may also have a similar length and powerful bite, allowing the predator to eat bony fish and orthocones (ancient relatives of squid), as well as other sharks.

Reconstruction of new Ctenacanthus sharks from Mammoth Cave National Park and northern Alabama. Glikmanius careforum appears in the foreground, with two Troglocladodus trimblei floating above it / Photo: NPS/Benji Paynose

Mammoth Cave is the world’s longest cave system, with more than 676 kilometers of passages cut through the limestone by underground streams and rivers. Experts have long studied the passages of Mammoth Cave as part of the Paleontological Resource Inventory, an ongoing study of fossils in several U.S. national parks. They now say that “dozens of fossilized sharks were found” in these tunnels.

• T. trimblei It was identified as a new genus and species from teeth of adults and juveniles from Alabama’s Mammoth Cave and Bangor Formation. To get to the first specimen of T. trimblei, “you have to crawl on your hands and knees for almost half a kilometer.
• G.careforum It was identified from teeth found in Mammoth Cave and in the Hartsell and Bangor Formations of Alabama. A partial jaw and gill set of this species was also found in the passage of the Mammoth Cave, which is too small for a human to fit in.

The fossils have not yet been excavated due to their fragility.