Japan's First Ankylosaur: Nipponopelta yezoensis

Publication Info:

Transcript:

S. Oyabu et al. A new nodosaurid ankylosaur (Dinosauria: Ornithischia) from the Upper Cretaceous Hikagenosawa Formation in Japan reveals dispersal pattern of Asian nodosaurid ankylosaurs. Cretaceous Research, published online August 21, 2026; doi: 10.1016/j.cretres.2026.106477

Meet Nipponopelta yezoensis, Japan's second new dinosaur of the week, and its first ankylosaur! These Cretaceous tanks roamed our planet alongside some of the most famous dinosaurs of all time, like Tyrannosaurus rex. Oddly enough, Nipponopelta seems to have more in common with its North American and European relatives than other ankylosaurs from Asia.

Episode 332

Notes:

Two brand new Japanese dinosaurs over the course of a week? Kind of looks like it. This partial skull was originally discovered in Hokkaido, Japan in the 2000s in a concretion along with a vertebra and a couple of teeth. And while they did get a rough identification at the time, it's now officially been described. I'll give you a hint, it's from a dinosaur group that's much more common in North America and Europe. They're heavily armored, generally have spikes, and sometimes tail clubs. A certain group of them is much more commonly found in coastal deposits. And to be clear, that doesn't mean they're active swimmers. I mean, actually there is some evidence that some of them may have been, but that's a story for a different time. Anyway, this is Nipponopelta yezoensis, the newly named Cretaceous nodosaurian ankylosaur from Japan. If you're not familiar with ankylosaurs, you are, you just don't realize it. They're the Cretaceous tanks, the turtley dinosaurs covered in armor and spikes. Some of them have tail clubs, although specifically the nodosaurians don't. They're really famous, well-known dinosaurs from Europe and North America, but Nipponapelta is the first species officially described from Japan. It's also only the second nodosaur ever found and described in Asia. And we're talking about official published descriptions, and that kind of matters, cuz what's weird about this one is it seems to be phylogenetically much more nested in with the more derived nodosaurians from North America and Europe rather than the nodosaurians previously found in Asia, which is going to bring up some great questions about how dinosaurs migrated around the planet. As usual, if you want more information, here's the source.