See Jason’s thread here for some interesting points bsky.app/profile/jdpa...

Permian reptiles keep challenging what we know about reptile origins 🦎👂 More to come!

BTW- the CT segmentation, reconstructions, and line drawings were done by ISU undergraduate Cy Marchant @slvrhwk.bsky.social…. He’d be a great fit for any paleo lab! 👀

At the same time, we see a suite of changes:
• loss of the lower temporal bar
• origin of a cephalic condyle
• increased cranial mobility

This raises the possibility that tympanic hearing and early cranial kinesis evolved together… much earlier than previously thought.

We suspect this anatomy was missed due to historical preparation techniques, especially in classic specimens like the Youngina holotype. 🔎

Newly discovered (and better-prepared) Youngina specimens all show the same feature….something that was even hinted at by Gow in the 70s….

That question led Valentin Buffa @valentinbuffa.bsky.social and I to re-examine all non-saurian neodiapsid taxa.

And we found tympanic fossae in more places than expected…. Even Youngina!

That’s a big deal because tympanic ears were thought to be restricted to living reptiles, and absent in Permian stem-reptiles.

So was Scyllacerta a weird outlier… or had something been overlooked in other fossil reptiles?

But the most exciting result?

Scyllacerta preserves a tympanic fossa on the quadrate.

This strongly suggests the presence of a tympanic (impedance-matching) ear. 👂

The scans made it immediately obvious that Scyllacerta is a distinct taxon.

It has a remarkably tooth-rich palate, including teeth extending onto the braincase (!) 🦷 🧠

During my PhD, I noticed several aspects of its anatomy that didn’t match Youngina at all.

So, with colleagues from Iziko Museums and University of the Witwatersrand, we CT-scanned the specimen at the European Synchrotron Radiation Facility. 🇫🇷

Even more recently, the holotype of Scyllacerta was referred to newly named Akkedops bremneri on the basis of them being from the same locality…..

But they are separated by hundreds of miles and millions of years in stratigraphy…. As are the other specimens to referred to Akkedops 👀 🤷‍♂️

Scyllacerta was first discovered in the early 1990s and originally identified as a juvenile aggregation of Youngina capensis.

But it was older (~257 Ma vs ~253 Ma) and from a different assemblage zone in South Africa (sus).

There may be a way to skirt this requirement by sneaking in a zip file, but this isn’t optimal obviously

There’s a way to batch upload, but I think you need permission…. It’s a huge pain without it.

I feel personally punished for working on complete skulls 💀

Check the paper out above👆 to learn more!!

Keep an eye out for future work by @valentinbuffa.bsky.social, myself, and others on early reptiles…. 🦎🐍🐢

Some exciting stuff inbound! (: