pterodactyloid

Caulkicephalus trimicrodon, an ornithocheirid pterosaur from the Early Cretaceous (~130 mya) of the Isle of Wight, carrying around a flapling in a similar manner to modern crocodiles.

We still know very little about the life cycle and reproduction of pterosaurs. The few known fossilized eggs had leathery shells, and may have been left buried in sand or vegetation. Baby pterosaurs (“flaplings”) seem to have been superprecocial, highly developed and possibly even capable of flight very soon after hatching.

Whether any actual parental care took place is also a mystery. So this is a rather speculative idea – but still adorable.

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Genus: Pterodaustro

…an extinct genus of pterodactyloid pterosaurs that lived in Early Cretaceous South America. This genus is noted for its tooth comb, which means it likely waded in water and filter fed like modern flamingos. It probably mashed hard crustaceans with its small teeth on its upper jaw. It was once thought that Pterodaustro was pink due to its diet like a flamingo, however recent studies show that only members of Neoaves can absorb those pigments and it was unlikely that any pterosaur was pink. Analysis of Pterodaustro's  scleral rings indicate that it might have been nocturnal and it might have lived like nocturnal anseriform birds.

Phylogeny

Animalia-Chordata-Reptilia-Pterosauria-Ctenochasmatidae-Ctenochasmatinae-Pterodaustro

Images: Mark Witton and Gadfium

Aerodactylus scolopaciceps by Steven Vidovic:

Aerodactylus scolopaciceps is a pterodactyloid pterosaur from the Solnhofen Plattenkalk of Bavaria, Germany. Aerodactylus was a Jurassic pterosaur, like Pterodactylus. It was in fact synonymous with Pterodactylus until 2014 when Vidovic and Martill erected the genus Aerodactylus for it.

(And yes, it’s named for the Pokémon.)

Pterosaurs came in an almost mind-boggling range of sizes.

The tiny Early Cretaceous Nemicolopterus had a wingspan of 25cm (10in), comparable to a modern sparrow. (Although it might actually be a baby Sinopterus. There were other pterosaurs only a little bit bigger, though, so we know they got pretty small!)

At the other end of the scale, huge Late Cretaceous azhdarchids like Quetzalcoatlus and Hatzegopteryx had wingspans of up to 11m (36ft). They also had really big heads – their skulls alone could be up to 3m long (10ft) – and rivaled giraffes in size when on the ground.

For a coastal species, there sure are very few illustrations of Pteranodon around coastal features. It’s always beaches and cliffs, which is why I decided to put these two in a sea cave, perhaps on an adventure of some sorts.

There are also woefully few images of purported female Pteranodon out there, all the attention seems to go to the larger, more spectacularly crested males, while the females are shoved into the background. This clearly doesn’t reflect nature, as female Pteranodon make up 2/3 of all Pteranodon specimens, so surely there should be a lot more of them showing up in palaeoart?

So to shake things up a little, here are two female Pteranodon, without a male in sight, exploring a sea cave.

The azhdarchid survivor of the K-T extinction event, and the common ancestor of the neoazhdarchids, pictured here next to the corpse of its larger relatives of the skies. It and creatures like it live on islands throughout the Americas and Europe. It has limited aquatic abilities and is omnivorous. It is a hardy survivor with limited nutritional needs. It would spread and give rise to the dominant megafauna of the cenozoic. 

This K-T extinction event killed different species than in OTL. Why some species survived OTL and others didn’t may have just come down to blind luck. The enantiornithines survived in greater numbers than their neoornithine cousins. Due to their restricted flight ability though, they would be outcompeted in the sky and become a vital part of the Cenozoic terrestrial fauna, diversifying just as the neoazhdarchids did

Mammals were hit harder than in OTL and, while still there, would not play as big of a role as in our world. They would still be relegated to burrows as archosaurs–birds, pterosaurs, and crocodylians, once more dominated the earth.

Nyctosaurus sebulbai by Jaime A. Headden:

No, this isn’t a real animal.

Nyctosaurids are pterosaurs with incredibly long arms, but comparatively short feet. Darren Naish once speculated ([link]) that pterosaurs could attain flightless status in much the same ways as birds do, with reduction of the forelimbs and wing form, developing elongated hindlimbs in azhdarchid-like taxa and thus become giraffe or horse-like “quadrupedasaurs.” I wonder if the selection on the wings for form are so intensive this could ever happen. Indeed, it seems that it would be the feet first to go, the wings second, if ever. What if, instead, we got pterosaurs who walked with their wings, freeing their feet from locomotion?

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On Lonchodectes

December 2, 2012

Reconstruction of Lonchodectes compressirostris’ skull. Note the incorrect seperated anteorbital fenestrae and nostrils; in pterodactyloids (which Lonchodectes defenitely was), they were fused into a single opening called “nasoanteorbital fenestrae” (a more slightly more accurate pterodactyloid skull on the right).

Due to their hollow bones with thin wals, pterosaur bones have quite some difficulty in not being destroyed. As such, the bulk of pterosaur specimens we have that do not come from lagerstattën are highly fragmentary; this pretty much helps with the notion that they didn’t decline, but it obviously has the unfortunate side effect of creating massive gaps in our understanding of these flying sauropsids.

One of the most iconic examples of the mysticism of pterosaur fragmentary remains is the often mentioned, but rarely explored Cretaceous pterodactyloid Lonchodectes. The original specimen, known as BMNH 39410, was discovered in a chalk formation in England, dating to the Turonian (making this one of the youngest known non-azhdarchid/pteranodontian pterosaurs). Originally identified as Pterodactylus compressirostris by Richard Owen in 1851, it was transfered to Ornithocheirus by Harry Govier Seeley roughly two decades later, before finally being recognised as it’s own genus by Reginald Walter Hooley in 1914 (who bizarrely also attributed the specimen as Ornithocheirus‘ holotype).

Subsequently, two other species, L. giganteus and L. daviesii, were also found, the first known from Cenomanian sediments while the latter dates all the way to the Albian, suggesting that this genus existed on this planet for a period of roughly 20 million years. Several other species formerly from Ornithocheirus and Pterodactylus were also added: L. saggitirostris, from the Hauterivian of Sussex (extending the temporal range to 39 million years), L. platystomus from the Aptian/Albian of Liaoning, and L. machaerorhynchus/microdon from the Albian deposits in the Cambridge Greensand.

Of these, only the last is considered dubious, as Alexander O. Averianov lumped it into Ornithostoma, another mysterious pterodactyloid (considered by Alexander to be an azhdarchoid, possibly related to tapejarids), though this is not considered to be an accurate statement.

Other possible lonchodectid remains have been reported from the Maastrichtian of India and Ross Island, though I haven’t checked the sources, and they might represent ornithocheirids instead. The mysterious australian pterosaur Mythunga has also been considered a lonchodectid in at least some sources.

What exactly is Lonchodectes?

Since it’s discovery as an independent genus, Lonchodectes has been consistently ping-ponged between Ornithocheiroidea and Azhdarchoidea. The latter is universally no longer considered to be a correct assertion, even more so due to the presence of teeth in Lonchodectes (Azhdarchoidea is notorious for it’s toothless taxa, after all). To my knowledge, an identity as an ornithocheiroid is also not taken seriously in most circles.

Recently, it seems fashionable to place lonchodectids within Ctenochasmatoidea, which would make them related to Pterodactylus after all. If so, Lonchodectes is among the youngest known ctenochasmatoids to exist.

The remains are far too fragmentary to attribute them any sort of lifestyle, but considering both ctenochasmatoids and non-euornithocheiroid ornithocheiroids generally fed on the ground or swimming, a stork-like lifestyle would make sense.

“Quetzalcoatlus” from Walking With Dinosaurs. Based on what little we have, Lonchodectes probably looked more or less like this; the model certainly fits the more stork-beaked Lonchodectes better than any azhdarchid.

Teeth and Crests by ~Eurwentala:

Here, have some quick pterosaurs.

Until today, I have mostly ignored all pterosaurs except azhdarchids and “rhamphorhynchoids”. Then I received my copy of Mark Wittons brand new pterosaur book, and this is what happened. I might have gotten a bit too excited, especially since I didn’t really have time for this.

During their 150 or so million years, pterosaurs invented quite a collection of weird head forms, beaks, fangs, head crests and impossibly long legs, necks wings or all of the mentioned. Here are a few of the heads that caught my attention.