Paleontologists have announced the identification of Tylosaurus rex, a newly described species of mosasaur that lived around 80 million years ago. This marine predator, measuring up to 43 feet (13 meters), was a dominant force in its ecosystem, much like its terrestrial counterpart, Tyrannosaurus rex. The study, led by Amelia Zietlow and published in the *Bulletin of the American Museum of Natural History*, involved extensive research on fossils previously attributed to Tylosaurus proriger. The fossils, found in Texas, revealed that Tylosaurus rex had distinct anatomical features, such as serrated teeth and a larger skull, indicating a more diverse genus than previously thought. The research underscores the significance of museum collections and community involvement in paleontology. Notably, Tylosaurus rex's discovery sheds light on the rich diversity of marine reptiles during the age of dinosaurs, emphasizing that these colossal creatures were formidable predators in the oceans, rivaling modern-day sharks. Future research projects are anticipated to further explore this fascinating marine reptile.