A new species of dinosaur the size of a multi-storey building has been discovered in Thailand

The size of the animal is impressive: about 27 metres long and about 27 tonnes in weight. This compares with the weight of nine adult Asian elephants. The front leg bone alone reached 1.78 metres - almost as tall as an adult human.

That said, the find is not exactly "fresh" in the domestic sense: the bones were discovered about ten years ago near the edge of a pond in northeastern Thailand. The news is that they have now been studied in enough detail to officially describe the new species.

Details

Nagatitan belonged to the sauropods, a large group of dinosaurs with long necks and long tails. The better-known diplodocs and brontosaurs also belonged to it. These dinosaurs fed on plants and were some of the largest animals ever to walk on land.

The palaeontologists studied the bones of the spine, ribs, pelvis and legs that were found. From their shape, the scientists realised that they were facing not just a large sauropod, but a new species. Particularly important were the details of the structure of the vertebrae, pelvis and limbs: it is such anatomical features allow to distinguish one species of dinosaur from another.

The name Nagatitan chaiyaphumensis was also chosen for a reason. Naga is a mythical water serpent from Thai and Southeast Asian tradition. Titan refers to titans from Greek mythology, and chaiyaphumensis means "from Chaiyaphum," the province of Thailand where the fossils were found.

According to the authors, Nagatitan was not the largest sauropod in Asia, but is now considered the largest known dinosaur in Southeast Asia. The scientific description estimates its mass at about 25-28 tonnes.

This giant lived in the early Cretaceous period. Then the territory of modern north-eastern Thailand looked different: there could be winding river systems, water bodies and dry or semi-dry areas. Sauropods probably did well in such conditions: their long necks helped them to reach vegetation, and their large size protected the adults from most predators.

Other dinosaurs may have lived near Nagatitan: smaller plant-eating species, large predators including relatives of Spinosaurus, and pterosaurs, flying reptiles that fished near rivers.

Why it matters

The discovery shows that Southeast Asia was an important region in dinosaur history, although its fossil record is less well-studied than finds from North America, Europe or China.

For Thailand, this is particularly significant, with Nagatitan becoming the 14th dinosaur to be named in the country. A few decades ago, local palaeontology was just developing, but now Thailand is gradually becoming a prominent point on the map of Cretaceous research.

The find also helps us understand how large sauropods dispersed across Asia and why some of them reached such a large size. The authors suggest that during the Cretaceous, a warming climate and the expansion of suitable habitats may have favoured the emergence of particularly large forms.

Background

Thailand's dinosaurs have only recently begun to be studied extensively, since around the 1980s. But in that time, many important fossils have been found in the country: both herbivorous and predatory species.

Nagatitan is also interesting because it was found in the youngest Thai geological formation where dinosaur remains are known so far. That's why researchers call it the "last titan" of Thailand. That doesn't mean he was the last dinosaur of the region literally. The point is different: younger rocks in this part of the country are probably already associated with shallow seas, which means there is less chance of finding new large land dinosaurs there.

That's why the find is important as more than just "another big dinosaur." It closes part of a gap in the region's history and shows what giants lived in what is now Thailand near the end of the local "dinosaur" record.

Source

Based on University College London press release and research paper: Thitiwoot Sethapanichsakul, Sasa-On Khansubha, Sita Manitkoon, Rattanaphorn Hanta, Philip Mannion, Paul Upchurch, "The first sauropod dinosaur from the Lower Cretaceous Khok Kruat Formation of Thailand enriches the diversity of somphospondylan titanosauriforms in southeast Asia", Scientific Reports, 2026. In the UCL Discovery database, the article is listed as a Scientific Reports publication with In press status.

The study describes the bones of a giant sauropod from the Lower Cretaceous Khok Kruat Formation in Thailand: vertebrae, ribs, pelvic and limb elements. Based on the structure of these bones, the authors identified a new species Nagatitan chaiyaphumensis and estimated the mass of the animal at about 25-28 tonnes.