Researchers have named a new dinosaur species, Uragasaurus kalasinensis, based on a single bone found in northeastern Thailand. The bone is a vertebra—part of the backbone—and it comes from a long-necked dinosaur that lived roughly 150 million years ago, during the Late Jurassic period. The discovery was published in Scientific Reports Nature by Dr. Apirat Nilphanaphan of Mahasarakham University BBC.

The dinosaur was a herbivore — it ate plants — and was enormous. Scientists estimate it reached about 20 meters long, roughly the length of a cricket pitch. That's the size of an adult blue whale.

One Bone to Name a Species

Naming a new dinosaur species from a single bone is unusual. Paleontologists — scientists who study dinosaur fossils — normally prefer multiple bones from the same skeleton to be sure they've actually found something new and not just a variation of an existing species. The fact that researchers did this with only one vertebra raised eyebrows Facebook/Phys.org, Yahoo News.

What made this one bone enough? Scientists scanned it with CT technology — the same machine used in hospitals — to see inside the bone. They found a distinctive Y-shaped arrangement of thin bony struts inside the vertebra, along with a unique pattern of air cavities. These air pockets connected to the dinosaur's breathing system and made the heavy skeleton lighter. The specific design of these air pockets is like a fingerprint: it helps scientists identify which family of long-necked dinosaurs a bone belongs to.

This fingerprint showed that Uragasaurus belonged to a group called Mamenchisauridae. These were extremely long-necked dinosaurs — even for sauropods, which were the longest-necked dinosaurs of all. Scientists think their extra-long necks let them reach high vegetation without moving their massive bodies around BBC.

Why Thailand Matters

Here's where this discovery becomes significant: almost all mamenchisaurids on record come from China. Mamenchisaurus itself, the group's namesake, and most of its known relatives lived in China during the Middle to Late Jurassic.

Uragasaurus kalasinensis is the first mamenchisaurid ever found in Thailand BBC.

The bone came from the Phu Noi site in the Lower Phu Kradung Formation, an area that has been producing dinosaur remains. More than 90 percent of all fossils found there are dinosaur fragments BBC. A local resident first spotted fragments at the site in 2008, thinking they were snake scales. Excavations since then have revealed this is a rich fossil deposit.

What This Tells Us About Dinosaur Distribution

Finding a mamenchisaurid in Thailand suggests that these Chinese dinosaurs roamed across a wider area of Southeast Asia than scientists previously knew. The region called the Indochina block — which includes modern-day Thailand, Laos, and Cambodia — appears to have supported these dinosaurs during the Jurassic period. Thailand's Khorat Plateau, where this bone was found, is becoming recognized as an important but still understudied window into how these long-necked giants spread across Asia.

One small bone doesn't rewrite prehistory on its own. But discoveries like this one gradually build the map scientists use to understand where dinosaurs lived and how their populations moved around the ancient world.

A Note on the Dates

Different news outlets reported slightly different ages for this dinosaur — about 150 million years old according to some sources, and 143 million years old according to others Times of India. A gap of seven million years may seem small to us, but it matters for placing this dinosaur alongside its Chinese relatives. The original scientific paper in Scientific Reports is the authoritative source on the true age, so that figure should be the one researchers and readers rely on as more details are published.

The real test will come next. If more bones or more mamenchisaurids turn up from Thailand or other parts of Southeast Asia, they may confirm what this single vertebra suggests. If not, this bone remains an intriguing hint about where these dinosaurs wandered.