Stealth predator sharks dating back 325 million years found in world’s largest cave

Recent excavations in Mammoth Cave, Kentucky, recognized as the world’s largest cave system at over 420 miles (675 km), have yielded two significant shark fossil finds dating back approximately 325 million years, researchers report

The fossils belong to two species of ctenacanth sharks: Troglocladodus trimblei and Glikmanius careforum. Both species are estimated to have reached lengths of 10–12 feet (3–3.6 m), comparable in size to today’s oceanic whitetip sharks.

The discovery of Glikmanius careforum pushes the origin of its family, Heslerodidae, back by over 50 million years.


These remains were embedded in limestone layers deposited during the Middle to Late Mississippian period, when much of eastern North America was submerged under a warm, shallow sea

A particularly notable aspect of this discovery is the preservation of cartilage, which rarely fossilizes. A juvenile Glikmanius careforum specimen includes intact jaw cartilage, offering fresh anatomical insights into early shark physiology

Paleontologist John‑Paul Hodnett, collaborating with the National Park Service Paleontology Program, highlighted the importance of these fossils for understanding shark diversification during the assembly of Pangea.

The cave's stable environment played a vital role in preserving fragile structures like cartilage .

Excavations remain active, with ongoing fieldwork uncovering additional specimens and refining our understanding of ancient marine ecosystems. The research has been submitted to the Journal of Vertebrate Paleontology