Gua Mammoth is the longest underground tunnel system in the world, spanning over 400 miles. The underground world of Gua Mammoth provides an ideal environment for preserving fossils. This is because the prehistoric materials contained within it are not affected by external elements, making these fossils often better preserved than those found on the surface that have undergone weathering. According to John Paul Hodnett, a paleontologist, in a stable environment like Gua Mammoth, fossils such as shark fossils can appear as if they were just discovered yesterday, as if they had just come out of a shark's mouth.

Two fossils from a new species of shark were found in a restricted area, only authorized researchers are allowed to enter. Anyone who wants to reach the fossil location must face a tough challenge. Hodnett explained, "To reach the fossil location, one must crawl a quarter mile with hands and knees." The discovery of these two shark species fossils happened accidentally. Initially, the researchers were on their way to examine the Glikmanius jaw fossil in 2019 when Trimble, the supervisor, suddenly found a fossil embedded in the cave ceiling.

The researchers have discovered two new species of sharks through fossil analysis in Mammoth Cave National Park, Kentucky. These fossils come from prehistoric fish believed to have lived over 325 million years ago, when all the current major continents were joined together as one landmass. The two species that were found are named Troglocladodus trimblei and Glikmanius careforum, and this announcement was made by the Mammoth Cave National Park Service. These two species are estimated to have a length of between 10 to 12 feet, similar to the size of modern-day cowboy sharks.