Giant New Tyrannosaur from New Mexico Reveals Hidden Cretaceous Predator Diversity!

Paleontologists have announced a mᴀssive new tyrannosaur from New Mexico’s Kirtland Formation that dramatically increases our understanding of apex predator diversity during the Late Cretaceous. The 74-million-year-old specimen, a partial skeleton including a 96-cm tibia and vertebrae, represents a giant tyrannosaurine estimated at 4.7–5 tonnes — roughly three-quarters the size of the largest Tyrannosaurus rex.

Recovered from the Hunter Wash Member near the Bisti/De-na-zin Wilderness, the bones display robust proportions and pneumatic features typical of tyrannosaurines. High-precision dating places it firmly in the late Campanian, making it the oldest known giant tyrannosaur from southern Laramidia.

Lead author Nicholas Longrich (University of Bath) explains: “This animal shows that the lineage leading to T. rex had already achieved enormous size in the southern Western Interior millions of years earlier than previously thought. It lived alongside other large predators, proving the ecosystem supported multiple giant carnivores.”

The discovery challenges the long-held view that a single giant tyrannosaur dominated each region. Instead, the southern ecosystems appear to have supported greater predator diversity, with this new taxon occupying a distinct niche from smaller tyrannosaurines also present in the same formation.

CT scans reveal rapid growth rates and powerful bite mechanics, confirming it was a top predator capable of tackling hadrosaurs and ceratopsians. The find underscores New Mexico’s status as a critical window into tyrannosaur evolution and Late Cretaceous food-web complexity.

As more material from the same horizon is prepared, this “Hunter Wash giant” promises to illuminate how multiple large predators coexisted and parтιтioned resources across the continent — rewriting the final chapters of dinosaur dominance before the end-Cretaceous extinction.