Wednesday, February 29, 2012

[Paleontology • 2011] ราชสีมาซอรัส สุรนารีเอ • Ratchasimasaurus suranareae • A New Iguanodontian Dinosaur from the Lower Cretaceous Khok Kruat Formation, Nakhon Ratchasima in Northeastern Thailand



Here we report a new iguanodontian dentary found from the Lower Cretaceous Khok Kruat Formation, Nakhon Ratchasima, northeast Thailand. A unique character, which is an elongated and flat shape of the dentary ramus, makes it possible to assign the specimen to the new genus of non-hadrosaurid iguanodontian, Ratchasimasaurus suranareae gen. et sp. nov. R. suranareae shows both primitive and derived characters, such as a caudally inclined coronoid process and alveolar trough with a primitive crown impression, and a derived buccal shelf between tooth row and coronoid process. The discovery of a new iguanodontian from the Indochina Terrene, considering that the previously reported “Probactrosaurus-like” iguanodontian, points out a great diversity of this group in the late Early Cretaceous in Thailand, and corresponds to the Asian iguanodontian diversity at that time.




Masateru Shibata, Pratueng Jintasakul, and Yoichi Azuma. 2011. A New Iguanodontian Dinosaur from the Lower Cretaceous Khok Kruat Formation, Nakhon Ratchasima in Northeastern Thailand. Acta Geologica Sinica - English Edition 85 (5): 969 – 976. DOI: 10.1111/j.1755-6724.2011.00230.x