Two new-to-science shark species that lived more than 325 million years were discovered recently, the National Park Service announced on Thursday.
The discovery was made through the Paleontological Resources Inventory at Mammoth Cave National Park in southern Kentucky.
Using fossils collected at Mammoth Cave and in northern Alabama, PRI researchers identified the shark species Troglocladodus trimblei and Glikmanius careforum.
An illustration of two Troglocladodus trimblei. (Benji Paynose / FOX Weather)
Troglocladodus trimblei is believed to have grown to about 10-12 feet long, or approximately the size of an oceanic whale tip shark, according to the NPS. It was identified by using adult and juvenile teeth.
Glikmanius careforum is believed to have been around the same size at 10-12 feet long, the NPS said. It was identified by using teeth found at Mammoth Cave and Alabama, along with a partial set of jaws and gills found at Mammoth Cave.
An illustration of Glikmanius careforum. (Benji Paynose / FOX Weather)
Finding shark fossils in what are now landlocked areas may seem puzzling. However, the NPS said that Kentucky and Alabama were once covered by water, being part of an ancient seaway more than 325 million years ago.
This seaway connected what is now eastern North America, Europe and northern Africa. This maritime passage eventually disappeared as all the continents merged to form the supercontinent Pangea, the NPS noted.
The first fossil specimen of Troglocladodus trimblei, which was found by Mammoth Cave National Park superintendent Barclay Trimble in the cave ceiling during an early fossil expedition. (JP Hodnett / National Park Service)
Because of this oceanic past, Troglocladodus trimblei and Glikmanius careforum are not the only ancient shark species to be identified in the region.
Mammoth Cave National Park officials announced in October the discovery of Strigilodus tollesonae, an extinct shark species more closely related to modern ratfish than to modern sharks and rays.