If you go to an average Thai island today, you find a very different “predator” to what existed 100 million years ago during the Cretaceous period. Instead of your average-IQ’d Australian male ‘gap yah’ backpacker, back in the age of dinosaurs there existed a group of ferocious carnivores called megaraptorans.
Megaraptorans were a group of medium- to large-sized dinosaurs with long snouts and large, elongated claws on their hands, ideal for slashing and gashing their prey.
Now, two new species of megaraptoran have been identified from the Sao Khua formation, famous for its dinosaur fossils – five theropod species alone have been named from here! The new additions are called Phuwiangvenator yaemniyomi and Vayuraptor nongbualamphuensis.
The first identified specimens of P. yaemniyomi were discovered by Preecha Sainongkham, a staff member of Phu Wiang Fossil Research Center and Dinosaur Museum in 1993. The name is in honor of Sudham Yaemniyom, former geologist of the Department of Mineral Resources, Bangkok, who found the first dinosaur bone of Thailand in 1976 at Phu Wiang Mountain.
The first fossils of Vayuraptor were discovered by Paladej Srisuk in 1988. Its genus name, Vayuraptor, comes from Sanskrit ‘Vayu’, the God of Winds, and the Latin ‘raptor’, meaning thief – so meaning ‘raptor of the wind’. All of the fossils for both species are currently housed at the Sirindhorn Museum, Kalasin Province, under the Department of Mineral Resources, in Thailand.
Why are they important
Fossils of their cousins are known almost only from Asia, with a couple of fragments known from South America and Australia. It is likely that the group formed a clade of top-tier predators that was endemic to the Asian continent back during the earlier parts of the Cretaceous period; while North America and Europe were dominated by groups like tyrannosaurs.
Either way, the fossil record of SE Asia still holds lots of promise in unraveling the ongoing evolutionary mysteries of the dinosaurs! Road trip, anyone?
Samathi, A., Chanthasit, P., and Sander, P.M. 2019. Two new basal coelurosaurian theropod dinosaurs from the Lower Cretaceous Sao Khua Formation of Thailand. Acta Palaeontologica Polonica 64 (2): 239–260. LINK.