Thailand's Mystery Spinosaurus

Publication Info:

Transcript:

Eric Buffetaut, et al. An Unusual Spinosaurid Tooth Morphotype from the Early Cretaceous of Eastern Thailand. Diversity 2026, 18(9), 557; doi: 10.3390/d18090557

Spinosaurids have been known from Thailand for years, but an unusual fossil tooth from Cretaceous deposits is bringing up some interesting questions about what different spinosaurid species were doing, and how they shared their ecosystem.

Episode 342

Notes:

There's a brand new Spinosaurus mystery out of Thailand. So, you're probably familiar with Spinosaurus. It's a household name at this point and most Spinosaurus teeth kind of look like this. This is a Moroccan tooth, most likely Spinosaurus aegyptiacus. It's conical, almost spear-like, has some light fluting, perfect for grabbing small, slippery prey. But, there are a ton of other spinosaurids, animals like Baryonyx and Suchomimus, and Irritator, and Suchomimus, depending on who you ask. They are almost all over the planet with the exception of the far northern latitudes, North America, and Antarctica. That said, the majority of the spinosaurids from Asia have teeth much more like this, with extremely distinct fluting, even a little more distinct than you can see on the larger spinosaurus specimen I showed you earlier. This is where things in Thailand are starting to get a little weird because spinosaurids have been known from Thailand and a lot of Asia since the '80s. I mean, confirmed since the '80s. People have been finding their fossils since the '60s. And most of them have that conical shape and those extremely distinct flutes or ridges. But, the Early Cretaceous Phu Wiang locality is mixing things up a little because there are two major morphotypes of spinosaurus teeth that have been found. Morphotype A, the expected, extremely conical, extremely fluted tooth. And then there's morphotype B. It's serrated. It's flatter. It's smoother, only having some ripples in the enamel with almost no fluting whatsoever. Meaning that this animal probably had a very different lifestyle than most of the spinosaurids in Asia. And it was living alongside a much more, let's say, normal spinosaurid. And yeah, there are multiple ecosystems around the planet that are now known to have had multiple spinosaurids at one time. But, now it looks like there were two very different spinosaurids doing very different things with their lives in eastern Thailand in the Early Cretaceous. And yeah, for the moment these are just teeth. And generally paleontologists aren't naming stuff off of just teeth anymore. But, it is going to be interesting to see with more specimens, more time, and more research what paleontologists can learn about these two very different, related animals that were living side by side. As usual, if you want more information, here's the source.