A team of paleontologists from Kasetsart University, Mahasarakham University and Sirindhorn Museum have unearthed three fossilized teeth from a previously unknown non-tyrannosaurid tyrannosauroid dinosaur in northeastern Thailand.

“Tyrannosauroidea is a lineage of theropods, which includes some of the best-known carnivorous dinosaurs. Tyrannosaurus Rex “From the Late Cretaceous of North America.” Dr. Chacharam Ketwetulya Kasetsart University and colleagues.

“They lived primarily on the supercontinent of Laurasia from the Middle Jurassic to the Late Cretaceous.”

“The oldest known species of tyrannosauroids are found in the Middle Jurassic of Europe and Asia, suggesting that this group of theropods originated within Eurasia.”

“Tyrannosauroidea ranged across Asia from the Late Jurassic to the Late Cretaceous, with most Asian tyrannosaurids found in China and Mongolia.”

The three tyrannosauroid teeth examined by the research team were discovered in the Phu Noi area of ​​Khammuang district, Kalasin province, northeastern Thailand.

The specimen dates back to the Tithonian stage of the Jurassic period, approximately 145 million years ago.

A basal tyrannosauroid tooth from the Phu Noi region of Thailand. Image courtesy of Chowchuvech others.

“The Phu Noi area is known to be one of the richest sources of Mesozoic vertebrate fossils in Southeast Asia,” the paleontologists said.

“Many species have been unearthed from the site, including freshwater sharks, ray-finned fish, lungfish, amphibians, turtles, crocodylomorphs, pterosaurs and dinosaurs.”

“Three species of dinosaurs have been identified in the Phu Noi area: a metriacanthosaurid theropod, a mamenchisaurid sauropod and a basal neoornithischian. Minimo Cursor.”

“Three of the theropod teeth from the Phu Noi area display unique dental features that distinguish them from previously discovered metriacanthosaurid theropods, including lateral teeth with twisted mesial ridges on the proximal lingual side that extend above the cervical line and interwoven enamel surface textures,” the researchers added.

“Morphological examination and systematic and morphometric analyses reveal that these isolated teeth indicate basal tyrannosauroid relationships, Five colors of the dragon and Proceratosaurus bradleyi From the Jurassic Period.”

“This discovery marks the first report of a tyrannosauroid from the Jurassic of Southeast Asia and contributes to our knowledge of the paleoecology of the lower continent.” Phu Kradung Formation“Our results shed light on the morphological and morphological distribution of tyrannosauroids during the Late Jurassic, and on the paleobiogeographic distribution of tyrannosauroids during the Late Jurassic,” the researchers concluded.

“Furthermore, this study sheds light on the possibility that future excavations and research may uncover new species of dinosaurs in Thailand.”

of study Published in the journal Tropical Natural History.

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W. Chochubek others2024. First discovery of a basal tyrannosauroid in Southeast Asia: dental evidence from the Late Jurassic of northeastern Thailand. Tropical Natural History 24（1） : 84-95