azhdarchids

The pterosaur Zhejiangopterus linhaiensis is in teh dinosaur base, eatin’ the all their dudes. Zhejiangopterus was an azhdarchid pterosaur from China, terrestrially stalking, as was (probably) their wont. I have given it a speculative soft-tissue crest — everything seems to have crests these days.

This composition is largely stolen from a painting by Christain Schloe. And thanks to Mark Witton for the skeletal reference.

P.S. Why is there an eye where the nostril should be? Your answer is in the question fish-bulb, that’s its nostril.

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Lythronax’s more news from the world of news!

Azhdarchids were the giant, stalking, terrifying marabou storks of the Cretaceous, armed with vicious beaks and elongate necks.

Well, as it turns out, the latest azhdarchid in town, from the Hateg basin (where Hatzegopteryx and Eurazhdarcho also lived), is both tiny and short-necked. Meet LPV (FGGUB) R.2395, an unnamed azhdarchid that was recently described by Darren Naish (of TetZoo fame). It’s definitely not a juvenile - the sole vertebra that remains of it is well-developed. This means that the prevalence of giant azhdarchids probably isn’t an evolutionary trend - it’s just that mini-azhdarchids aren’t found as often.

Reconstruction and diagram from Mark Witton’s excellent post here.

A popular motif in classical mythology is that of Zeus turning into a swan and raping a maiden named Leda in a fit of lust. Here, I imagined the same scenario with the closest animal there was to a “giant swan,” a flying reptile known as Zhejiangopterus. The impossible union has unfortunately resulted in the monster piercing the maiden through the heart.

www.cmkosemen.com

A far-fetched idea for a neoazhdarchid pterosaur, convergent with whales. The idea for the hind flipper is quite novel, and I wonder if there’s a precedent for it in tetrapods. Its fin is formed by a fusion of the hindlimbs, specifically the medial-most tarsal and all of digit I distal to it. The other digits are flattened and spread out to form the basis of the flipper. The flipper, having joints, is more malleable than that of a whale; its shape can be changed, granting Pterocetus more control and more maneuverability. However, the rear fin is not as powerful as a whale’s, and thus the fore and hind limbs work together to provide power.

The flight muscles have been repurposed as swimming muscles, so a lot of basic Pterosaur shoulder and forelimb anatomy is maintained. Digit IV (the former wing finger) is reduced, while the others are enlarged. The pteroid acts simply to provide support, but is mostly vestigial.

I imagine this evolving from a penguin/otter-like thing, which then evolved into something like a walrus. This means that, before osteo-fusion, the hindlimbs were joined by muscle. The tail isn’t used for the back flipper as it was fused into a pygostyle or coccyx before this line of evolution began. Instead, the bones of the hind limbs act sort of like replacement vertebrae, by convergent evolution.

I’d love to hear people’s thoughts on this. I’m going to be doing mostly earlier Neoazhdarchids and work my way slowly up through the cenozoic, but this was too strange NOT to draw.