Palaeontologists have identified a new species of long-necked dinosaur, Uragasaurus kalasinensis, from fossils unearthed in Thailand’s Kalasin Province. Dating back approximately 150 million years, this herbivorous sauropod measured up to 20 meters in length and features unique anatomical structures that distinguish it from all other known dinosaurs in the world.
Discovery at the Phu Noi Fossil Site
The discovery of Uragasaurus kalasinensis stems from a long-term excavation project at the Phu Noi site in Thailand's north-east. The site was first identified in 2008 after a local resident discovered fossilized fragments that resembled serpent scales.
While the site yielded a diverse array of teeth and bones, the breakthrough occurred when researchers recovered a specific dorsal vertebra—a bone from the middle or upper back. This specimen displayed distinct characteristics that prompted a deeper scientific investigation.
Anatomical Features and the Mamenchisauridae Family
Detailed CT scans performed on the vertebra confirmed that the dinosaur belongs to the Mamenchisauridae family, a group of sauropods renowned for their extremely long necks. These physical traits likely allowed the herbivore to graze on vegetation at varying heights, a common adaptation for the family.
However, the Thai specimen possesses specific traits that separate it from its relatives typically found in China. The scans revealed a unique Y-shaped arrangement of supporting bones known as laminae, alongside a distinct air-cavity structure. According to the study’s lead author, Dr. Apirut Nilpanapan, these features are unlike any other dinosaur in the world… That’s what sets it apart
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Scientific Significance and Researcher Reaction
The identification of Uragasaurus kalasinensis marks the first time a member of the Mamenchisauridae family has been discovered in Thailand.
Unlike any other dinosaur in the world…
Dr. Apirut Nilpanapan, Mahasarakham University
Dr. Nilpanapan described the discovery as a career-defining event, noting that he felt exhilarated and relieved after confirming the unique nature of the fossils, even jokingly admitting he smashed his computer in the excitement of the breakthrough.
Contextualizing Thailand’s Fossil Record
This discovery follows a string of significant findings in the region. In May, researchers identified the nagatitan, another long-necked herbivore unearthed in Thailand. The nagatitan stands as the largest dinosaur ever found in South-East Asia, measuring 27 meters (88ft) in length and weighing approximately 27 tonnes—the equivalent of nine adult Asian elephants.
