Rare armored dinosaur found in Japan may have ancestors that migrated across a land bridge 100 million years ago

Rare fossils discovered in Japan more than 30 years ago are from a new species of armored dinosaur — one whose ancestors likely reached Asia by trekking across a land bridge, a new study finds.

The newly named dinosaur, a type of nodosaurid, is now one of just three species of its kind found in Asia to date. The scarcity of nodosaurids in Asia, and the fact that the newly described beast is similar anatomically to those from North America, hint that its species likely arose from a migration from North America to Asia via the Bering Land Bridge, an ancient strip of land that connected present-day Alaska and Russia, researchers reported in the February 2027 issue of the journal Cretaceous Research .

"It's super cool to see [the specimen] getting a new look and a new name," said Victoria Arbour , manager of research and collections at the Royal B.C. Museum in Canada. Arbour was not involved in the new work.

Nodosaurids are armored dinosaurs covered in bony plates. They are closely related to ankylosaurids, but they lack the heavy tail clubs ankylosaurids used to protect themselves from predators. Nodosaurid fossils have primarily been found in North America and Europe, though a few have been uncovered in Asia.

In the new study, a team of researchers revisited one such fossil specimen originally discovered in 1995 on Hokkaido, the northernmost main island of Japan. The scientists performed computed tomography (CT) scans of the fossils, which are somewhere between 93 million and 100 million years old, and include the back of the skull, part of the lower jaw, and several teeth and bony plates.

CT scanning enables researchers to make digital 3D models of specimens, and "lets you just get more information than you'd be able to have otherwise, because you can look inside without breaking [the fossil]," Arbour told Live Science.

Based on the CT scans and an anatomical analysis, the team determined that the fossils represented a new species of nodosaurid, which they dubbed Nipponopelta yezoensis . "Nippon" refers to Japan, and "pelta" means "shield" in Greek. "Yezo" is the traditional name for Hokkaido.

Get the world’s most fascinating discoveries delivered straight to your inbox.