Southeast Asia’s “last titan”: Giant new dinosaur species identified in Thailand

Researchers from University College London and several Thai institutions have identified Nagatitan chaiyaphumensis, the largest dinosaur ever discovered in Southeast Asia. This 27-tonne long-necked sauropod lived in Thailand approximately 100 to 120 million years ago

Dimensions and classification

Nagatitan belonged to the sauropod family, the group of long-necked plant-eaters that includes well-known species like Brontosaurus. Analysis of the fossilised spine, pelvis, and limbs—including a front leg bone as tall as a human—indicates the animal reached 27 metres in length. At an estimated 27 tonnes, it was significantly larger than the famous Diplodocus, weighing roughly the equivalent of nine adult Asian elephants.

The team classified Nagatitan as a member of the Euhelopodidae, a specific subgroup of sauropods found only in Asia. Its name honours the Naga, a serpent from Southeast Asian folklore, and the province of Chaiyaphum, where the bones were first unearthed a decade ago.

The “last titan” of the Cretaceous

Lead author Thitiwoot Sethapanichsakul refers to the species as the “last titan” because it was found in Thailand’s youngest dinosaur-bearing rock formation. During the Early Cretaceous, the region transitioned into a shallow sea, meaning younger rocks are unlikely to contain large dinosaur remains. This makes Nagatitan one of the final giant sauropods to inhabit the area before the environmental shift.

The dinosaur lived in an arid to semi-arid environment characterised by meandering river systems. Its massive body size and long neck likely helped it regulate its temperature in the heat. It shared this habitat with various freshwater sharks, crocodiles, and other dinosaurs, including early relatives of Triceratops and large meat-eating theropods.

International collaboration and technology

The discovery is the result of a new partnership between UCL and Thai researchers, utilising modern technology to bridge the distance between institutions. Researchers used 3D scanning and printing to analyse the specimens, allowing for detailed study and data collection in London without moving the original fossils from Thailand.

Project leaders noted that while Thailand is a relatively small country, it possesses a high diversity of fossils, ranking among the top three in Asia for dinosaur remains. The study, funded by the National Geographic Society, highlights the growing community of palaeontologists in Thailand who are working to place the region’s unique prehistoric history into a global context.