An article published in the “Bulletin of the American Museum of Natural History” reports the identification of a new species of mosasaur, named Tylosaurus rex because its characteristics indicate it was a massive and fierce predator. A team of researchers reexamined Tylosaurus fossils previously attributed to other species of this taxonomic genus of mosasaurs, concluding that some specimens had anatomical characteristics different enough to warrant assignment to a new species.
Mosasaurs are a group of marine reptiles that lived during the Cretaceous Period. They have been known for nearly three centuries, so their history is fairly well understood. Within this reptile group, the Tylosaurus genus had typical mosasaur characteristics, such as an elongated body and long tail, as well as other specific features, such as an elongated snout with distinctive jaw and dental structures. They were also the first mosasaurs to reach considerable size.
A century and a half after the first Tylosaurus was described, fossils attributed to this taxonomic genus have been found in many parts of the world. This means that many specimens are part of museum collections on different continents. This new study began when Dr. Amelia Zietlow, a paleontologist then studying for her doctorate, noticed a fossil at the American Museum of Natural History attributed to the species Tylosaurus proriger and deemed the assignment incorrect.
This marked the beginning of a re-examination of various fossils attributed to the species Tylosaurus proriger. Dr. Amelia Zietlow and her colleagues compared these fossils with the holotype of Tylosaurus proriger and concluded that several specimens displayed different anatomical characteristics and therefore actually belonged to another species, which they named Tylosaurus rex.
In the end, the specimens attributed to the species Tylosaurus proriger after this study were found primarily in present-day Kansas and date back approximately 84 million years. The specimens attributed to the new species Tylosaurus rex were found primarily in present-day Texas and date back approximately 80 million years.
The findings of this study indicate that Tylosaurus rex was a massive, aggressive predator, reaching 13 meters in length. It had powerful jaws and neck muscles, making it a lethal hunter. The specimen nicknamed “The Black Knight” shows signs of a brutal fight, which were attributed to a clash with another member of its species.
The name of the new species, which becomes the T. rex of mosasaurs, gives this study greater visibility than others in the field of paleontology. However, its scientific importance lies in the fact that it helps reconstruct the evolutionary history of mosasaurs and the understanding of the ecosystem that existed in present-day Texas about 80 million years ago.
