David Bridges
In 2021, researchers made a significant yet controversial discovery of a new mosasaur species following the unearthing of a Cretaceous-period jaw featuring remarkable teeth in a mine located in Morocco. However, this exciting find faces serious scrutiny as there are claims that the remains may have been artificially created or altered.
Canadian researchers have raised critical questions regarding the authenticity of the fossil attributed to the newly identified species of extinct marine reptile, Xenodens calminechari, which was announced in 2021. Their extensive analysis, published on December 16 in The Anatomical Record, reveals inconsistencies in the original research and advocates for advanced CT scans of the jaw to verify its legitimacy. This new perspective may influence how future discoveries are validated.
If the doubts raised are substantiated, Henry Sharpe, a leading researcher from the University of Alberta, emphasized to Live Science that it would be imperative to formally document that this specimen is indeed a forgery within the scientific literature.
Our rebuttal to “Xenodens” is now published open-access in The Anatomical Record: this bizarre “shark-toothed” mosasaur is likely both a forgery and nondiagnostic (🧵) pic.twitter.com/9s1UWMYJaw
— Hank Sharpe (@Paleoartologist) December 17, 2024
Mosasaurs were formidable marine reptiles, dominating the oceans as apex predators during the Cretaceous period, which spanned from approximately 145.5 million to 66 million years ago. Some individual mosasaurs reached astonishing lengths of up to 56 feet (17 meters). In the original study from 2021, researchers based their identification of this new species on four distinct, sharp teeth discovered on an incomplete jawbone, which has been dated to between 72.1 and 66 million years ago, and excavated from a phosphate mine in Morocco known for yielding significant paleontological finds.
The researchers, led by Nicholas R. Longrich from the University of Bath, described the new mosasaurid as exhibiting a unique dental arrangement, termed a dental battery, characterized by numerous small, short, bladelike teeth closely packed to create a serrated cutting edge. They posited that this was the first instance of such a tooth arrangement found in tetrapods (four-limbed vertebrates), a claim that prompted Sharpe and his colleagues to delve deeper into the anatomical characteristics of the fossil.
Notably, two of the teeth observed on the purported jaw of X. calminechari were found to occupy a single tooth socket, a feature that deviates from the typical structure seen in known mosasaurs, where each tooth is anchored in its own dedicated socket. This discrepancy raises questions about the fossil’s credibility, as mosasaur tooth sockets are formed from the bone of the individual teeth rather than the jawbone itself, as explained by Michael Caldwell from the University of Alberta, who also contributed to the current study.
“Whenever a tooth is lost, it leaves behind a significant pit, which is subsequently filled by the next developing tooth, reinforcing its secure attachment within the jaw,” he elaborated to Live Science. Moreover, Sharpe’s research team identified possible traces of adhesive materials and noted that the unusual overlap of tissue between the two teeth could be indicative of forgery, as outlined in their study.
In addition to the peculiarities of the teeth themselves, the circumstances surrounding the discovery of the jaw in Morocco’s Khouribga province raise further concerns regarding its authenticity. The fossil was reportedly “obtained nonscientifically (without technical supervision) from an area in Morocco known for producing numerous manipulated or forged specimens,” as stated in the researchers’ findings. This aspect of the discovery warrants further investigation.
The research team ultimately proposes that the teeth and jaw may not even belong to the same species, suggesting that advanced CT scans of the remains could provide clarity on this matter. It remains uncertain whether the researchers will be able to utilize this technology on the X. calminechari fossil or persuade others to pursue this critical analysis in the foreseeable future. For now, exercise caution when encountering references to this new mosasaur with its peculiar dental features!
Daniel Mercer
Brandon Fletcher
