Spinosaurid theropod teeth from the Red Beds of the Khok Kruat Formation (Early Cretaceous) in Northeastern Thailand

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Teeth from the Aptian – Albian Khok Kruat Formation of the Khorat Group in Northeastern Thailand, are described as belonging to spinosaurine dinosaurs. They consist of two morphotypes, i.e., the Khok Kruat morphotype and Siamosaurus morphotype. The Khok Kruat morphotype shows fine ridges and a smooth enamel surface of the crown while the Siamosaurus morphotype shows coarse ridges and a wrinkled enamel surface. Comparisons of the Thai material with the teeth of Asian and other spinosaurids indicate that the Khok Kruat morphotype is similar to other Asian spinosaurid teeth and more closely to those of Siamosaurus suteethorni or Siamosaurus morphotype from the older Sao Khua Formation of Northeastern Thailand. The differences in their morphology indicate a greater diversity of spinosaurids in Thailand and Asia.


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WONGKO, K., BUFFETAUT, E., KHAMHA, S., & LAUPRASERT, K. (2019). Spinosaurid theropod teeth from the Red Beds of the Khok Kruat Formation (Early Cretaceous) in Northeastern Thailand. Tropical Natural History, 19(1), 8-20. Retrieved from https://www.tci-thaijo.org/index.php/tnh/article/view/181194
Author Biographies

KAMONLAK WONGKO, Department of Biology, Faculty of Science, Mahasarakham University, Maha Sarakham, 44150, THAILAND

Department of Mineral Resources, Khon Kaen, 40150, THAILAND

ERIC BUFFETAUT, CNRS, UMR 8538, Laboratoire de Géologie de l’Ecole Normale Supérieure, PSL Research University, 24 rue Lhomond, 75231 Paris Cedex 05, FRANCE

Palaeontological Research and Education Centre, Mahasarakham University,

Maha Sarakham, 44150, THAILAND


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