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Here is a link to a wonderful thread by @stephanspiekman.bsky.social about this amazing paper! Thank you so much for entrusting me with reconstructing this amazing animal bsky.app/profile/step...

The fish scales are only found in the intestinal region, actually. We made the common mistake of calling any gut content "stomach content"! See one of the supp figs here for the position of the scales.

Second, we'd expect the lungs to reach further anteriorly, reaching to between the pectoral girdles. Also, lungs are extremely fragile and virtually never fossilize (I don't know a single Triassic example), whereas there are quite some (partial) cases of stomach preservation in marine reptiles.

That's a good question and we pondered this for a long time. First, the liver isn't necessarily posterior to the stomach, but seems to be largely covered by it, with only its posterior portion sticking out. You can see how far anteriorly the liver extends in the ventral part of the body cavity.

Spectacular discovery: Researchers, including Dr. @stephanspiekman.bsky.social (Natural History Museum Stuttgart & @unihohenheim.bsky.social) have, for the first time, identified parts of the digestive system in a 245-million-year-old marine reptile from China. Press release: https://t1p.de/7e2wr

Many thanks to Wei Wang and Chun Li for the opportunity to contribute to this amazing project, and thanks to the entire team for the great collaboration. And thanks to @serpenillus.bsky.social for this stunning reconstruction! @smnstuttgart.bsky.social @unihohenheim.bsky.social @dfg.de

Exceptionally, the fossil preserves an intact stomach, liver (incl reddish hue and high iron contents) and intestine. The simple stomach shows that the double chambered stomach of birds and crocs likely evolved later in archosauromorph evolution. And the short intestine befits a fish-eating reptile

Its limb proportions are similar to mosasaurs and ichthyosaurs, suggesting the front limbs were mainly used for steering and the tail for propulsion. Austronaga was clearly an excellent swimmer, more so than we ever imagined for an archosauromorph. But the story doesn't end there...

Austronaga exhibits hyperphalangy (an increase in phalanges to increase flipper surface area), enhanced forelimbs and a strong reduction of the hindlimb, including a loss of articulation between the sacrum and pelvis. This allows it to optimise its centre of mass for underwater locomotion

Trachelosaurids show extensive marine adaptations, including an increase in presacral vertebral count, flippered limbs, and viviparity (giving birth to live young). But Austronaga takes these aquatic adaptations even further...

There is an exception to this rule though, and of course it can be found in the Triassic, the ultimate time of reptile innovation! In recent years, we identified a clade of highly marine archosauromorphs: Trachelosauridae, which includes the charismatic 'Chinese Sea Dragon' Dinocephalosaurus

Archosauromorphs (crocs, birds and their relatives), dominated the land during the Mesozoic. Although they also invaded the oceans several times (think penguins or thalattosuchians - oceangoing crocs), their aquatic adaptations never rivaled those of ichthyosaurs, plesiosaurs, or mosasaurs

Excited to share our new paper in Science Advances! Led by Dr Wei Wang at #IVPP in Beijing, it presents a complete skeleton of #Austronaga, the most marine of all archosauromorphs. To boot, this fossil preserves the oldest complete digestive tract of any reptile! www.science.org/doi/10.1126/...

Congrats Brandon! Great to have you strengthen European vertebrate paleo :)

Today is my first day in office as the new curator of vertebrate paleontology at @nhmdk.bsky.social & @ucph.bsky.social! 🇩🇰 🏛️ 🦴 🦕 😁 Starting off right with some proper Paleozoic Greenlandic friends (🐟/🐸, 🦈) and an extremely Danish office surprise! 🧱

Proud to share our latest paper in out in Nature today on the origin of #snakes. We present Tametara mirim, an articulated 3D preserved stem snake from the Late Cretaceous of Brazil. Tametara helped us re-tell the story of snake origins in a novel way... www.nature.com/articles/s41...

Exceptional brain and ecological diversity in the earliest snakes - NatureA well-preserved fossil snake from the Late Cretaceous of Brazil shows early ecological and brain shape disparity in the group.www.nature.com

Just in time for the weekend: this new skull fills a big gap in the formation of the bulldog-like🐶 rhynchosaur skull, which we also use as an excuse to review all of rhynchosaur skull evolution! Another Triassic weirdo off my bucket list✅ @smnstuttgart.bsky.social @unihohenheim.bsky.social @dfg.de

Our paper on turtle origins is finally out in Current Biology, with two major implications for our understanding of reptile evolution 🐢 #Paleontology #Turtles #Evolution www.cell.com/current-biol...

Thanks Brandon, that's great to hear!

Thanks Gabi! :)