2026/01/01 by Kenshu Shimada, Mette Elstrup, Henrik Lauridsen +2 · 1 voice
Environmental Science · Earth and Planetary Sciences · #Ichthyology and Marine Biology #Paleontology and Evolutionary Biology #Crustacean biology and ecology
paper · doi:10.26879/1674
The extinct megatooth shark, Otodus megalodon, is an iconic Neogene shark that may have reached as much as 24.3 m in total length (TL). The 24.3 m TL estimate was partly based on published photographs of an associated set of vertebrae from the Upper Miocene Gram Formation in Gram, Denmark, some of which allegedly had a diameter of 23 cm. Here, we report on the rediscovery of the specimen, which was thought to be lost, confirming the reported maximum diameter of 23 cm. Those vertebrae co-occurred with remains of a cetorhinid (basking shark), but the morphology and size assessments of the vertebrae suggest that they belong to O. megalodon, with the possibility that the cetorhinid remains represent stomach content of the megatooth shark. The vertebral specimen of O. megalodon was also used to decipher its ontogenetic growth patterns, and this study suggests that this specific individual had the potential to grow even slightly larger than 24.3 m. However, the growth model presented in this work must be viewed as highly tentative. Nevertheless, the O. megalodon specimen described herein is significant because it represents the largest shark vertebral specimen known to date, and quite possibly even the largest non-tetrapod vertebrae ever recorded. Ultimately, a more complete skeletal specimen of O. megalodon, ideally with associated teeth, is required for any further discussion on the maximum possible size of the fossil species.