A team of paleontologists identified two new shark species from fossils found in Kentucky’s Mammoth Cave and northern Alabama in May 2025. The Carboniferous predators lived more than 325 million years ago and are estimated to have reached 3–3.6 meters.
The species are Troglocladodus trimblei and Glikmanius careforum, both ctenacanths. T. trimblei had fork-shaped teeth that may have helped it target prey; G. careforum is described as having a powerful bite. Both had comb-shaped back spines thought to deter larger predators.
The rock containing the fossils formed on the floor of a broad sea that covered much of North America during the sharks’ era. The article says marine remains were buried in sediment that later became limestone as ancient seas retreated and continents shifted.
