At its size, it had very little to fear from predation
The herbivorous sauropod lived 113 million years ago and was so massive that adult predators posed minimal threat to it in its ecosystem. Named after the mythical Naga serpent, this specimen represents the last giant sauropod to inhabit Southeast Asia before the region became shallow sea.
- Nagatitan chaiyaphumensis: 27 meters long, 25-28 tons, lived 113 million years ago
- Discovered in Chaiyaphum Province, northeastern Thailand; fossils excavated over several years
- Largest sauropod ever found in Southeast Asia; named after the mythical Naga serpent
- Lived during period of elevated atmospheric CO2 and high global temperatures
Scientists discovered fossils of Nagatitan chaiyaphumensis, a 27-meter sauropod weighing up to 28 tons, the largest dinosaur ever found in Southeast Asia, in northeastern Thailand.
One hundred and thirteen million years ago, a creature nearly as long as a tennis court moved through the hot, dry landscape of what is now northeastern Thailand, reaching up into the canopy to feed on conifers and seed ferns without much concern for the predators around it. Its name is Nagatitan chaiyaphumensis, and it has just become the largest dinosaur ever discovered in Southeast Asia.
The skeleton was first spotted by a villager in Chaiyaphum Province, in Thailand's northeast. Over the course of several years, paleontologists carefully excavated the bones—vertebrae, ribs, pelvis, legs, and a single forearm bone, or humerus, that stretched nearly six feet long. Based on these dimensions, researchers estimate the animal weighed between 25 and 28 tons and measured just under 27 meters from nose to tail. The head and teeth were never found, but scientists have a clear picture of what this sauropod ate. It was a generalist herbivore, the kind of animal that could consume enormous quantities of vegetation with minimal chewing, stripping leaves and fronds without the need for sophisticated dental work.
Thitiwoot Sethapanichsakul, a paleontology doctoral student at University College London and lead author of the study published this week in Scientific Reports, explained that the animal's sheer size was its primary defense. The largest predator in its ecosystem was a relative of the African giant Carcharodontosaurus—a fearsome hunter by any measure, but one that topped out at around eight meters and 3.5 tons. Next to Nagatitan chaiyaphumensis at full size, it was dwarfed. Adult sauropods of this magnitude likely had little to fear from predation, though younger animals and the elderly or infirm may have been vulnerable. Sauropods grew with remarkable speed after hatching, a strategy that made evolutionary sense: the faster they reached adult size, the safer they became.
The creature lived in a world populated by other dinosaurs, pterosaurs, and a river system teeming with crocodiles, fish, and freshwater sharks. It belonged to a subgroup of sauropods whose bones were riddled with air sacs and thin walls—architectural features that kept their massive skeletons surprisingly light. This lineage emerged roughly 140 million years ago and eventually spread across the globe. By 90 million years ago, it was the only sauropod group left on Earth, and it persisted until the asteroid impact 66 million years ago that ended the age of dinosaurs.
The name Nagatitan references the Naga, a serpentine being from Asian religious traditions depicted in Thai temples. It is an apt choice, and Sethapanichsakul argues it is also fitting to call this species the last titan of Southeast Asia. The region later became a shallow sea during the Cretaceous, meaning no other sauropod would ever inhabit it again. Thailand has yielded 14 named dinosaur species in total, but none as large or as recent as this one.
Paul Upchurch, a paleontologist at University College London and coauthor of the study, noted that the discovery fits a broader pattern. During the time Nagatitan chaiyaphumensis roamed Thailand, atmospheric carbon dioxide was rising and global temperatures were climbing. Under these conditions, sauropods became particularly enormous. Gigantic forms were living in South America, in China, probably in North Africa, and now, with this specimen, a reasonably large one was thriving in Southeast Asia. The fossil record suggests that extreme size and extreme heat went hand in hand, at least for these remarkable animals.
Notable Quotes
At its maximum size, it probably had very little to fear in terms of predation— Thitiwoot Sethapanichsakul, lead paleontologist
Sauropods appear to have become particularly large during this time, with gigantic forms living in South America, China, probably North Africa, and now with this specimen in Southeast Asia— Paul Upchurch, University College London
The Hearth Conversation Another angle on the story
Why does a dinosaur discovered in Thailand matter to people who will never see it?
Because it tells us how life adapted during a period of rapid climate change. When CO2 was high and the world was hot, sauropods grew to their largest sizes across multiple continents. We're living through our own period of rising atmospheric carbon. Understanding how ecosystems responded then gives us a lens for thinking about now.
But this animal was herbivorous. It wasn't hunting anything, wasn't competing with humans. What's the actual consequence?
The consequence is knowledge about diversity. We know very little about Southeast Asian dinosaurs compared to what we know about South America or China. This find expands the map. It shows us that the giants weren't confined to one region—they were a global phenomenon during certain climatic windows. That changes how we understand the distribution of life.
The villager who found it—did they know what they were looking at?
The source doesn't say. A local person spotted bones in the ground and reported it. Scientists then spent years excavating. That's how most major discoveries happen. Someone notices something unusual, and then the slow work begins.
Why is it called the "last" titan of Southeast Asia?
Because the region became a shallow sea later in the Cretaceous. The geography changed. Sauropods need land, vegetation, space to roam. When the ocean came in, there was nowhere for them to live. This specimen represents the final chapter of giant sauropods in that part of the world.
Could an animal this size actually exist? Isn't there a physical limit?
There is, and sauropods pushed right up against it. Their bones were hollow, filled with air sacs like birds. That kept them light relative to their length. But yes, there's a ceiling. Some South American sauropods were even larger—over 30 meters. But Nagatitan chaiyaphumensis was enormous by any standard.