pterodactyloids

3

Nemicolopterus crypticus: A baby pterosaur, or just small?

Size: 10 inches (25 centimeters) from wingtip to wingtip.

Time Period: The Aptian stage of the Early Cretaceous Period.

Locale: The Jiufotang Formation of China.

Name: The generic name means “forest-dwelling wing,” in reference to the animal’s presumed forest habitat. The specific name means “hidden.”

Pterosaurs astonish us humans because they were strange prehistoric creatures that lived in the sky. They looked a bit like birds, but were incredibly foreign in comparison to our feathered friends. Most astonishing of all is the size of some pterosaurs. Animals like Hatzegopteryx and Aerotitan grew to sizes never seen in other flying animals. However, not all pterosaurs were as huge and macho as the azhdarchids. Some were pretty tiny.

One such “ptiny pterosaur” is Nemicolopterus, a Chinese pterodactyloid that is currently identified as the smallest pterosaur of all. However, there might not be as much truth to this as you’d think. The fossil specimen is actually smaller than any (excepting a choice few) hatchling pterosaur, but it isn’t fully grown. Darren Naish has argued that, since pterosaurs are able to be out and about from an early age, bone fusion and ossification can occur very quickly. Factoring this into our catalog of Jiufotang faunal assemblages, we can guess that Nemicolopterus may be a hatchling of the genus Sinopterus, a decently sized tapejarid from the same area. 

All that discussion aside, there are some concrete conclusions to be made about this little fellow. Nemicolopterus is toothless, and may be an intermediate between the ornithocheiroids and dsungaripteroids. Though Nemicolopterus isn’t the best representative of its relatives’ size, some of its relatives may have evolved into the aforementioned macho pterosaurs (such as Aerotitan).

We can also confidently assert that we know just about where Nemicolopterus lived. Since this pterosaur demonstrates adaptions for grasping tree branches, it may have hunted for insects and lived in the canopy of a forest. Though most pterosaurs are known from marine sediments, and would have probably caught fish in the sea and landed on nearby structures to eat and mate, it’s clear that Nemicolopterus was found in the continental interior of its area, making it one of the few pterosaurs known to live in such a habitat. Other inland pterosaurs include Quetzalcoatlus, a “Ptexan pterosaur” whose inland habitat was originally given as evidence that it was a vulture-like scavenger. Tapejaridae, the family that Sinopterus (Nemicolopterus’s presumed adult version) belongs to, also shows similar adaptions despite the fact that some were marine.

So, though Nemicolopterus may have only been a juvenile specimen of Sinopterus, it’s still interesting. It might make us reconsider our phylogenetic assignments of other small pterosaurs, and it is one of the few inland pterosaurs discovered thus far. As we have piece together the puzzle of pterosaur “ptylogeny (okay, I tried),” we find that a bit more investigation may be required to correctly determine the identity of some flying reptiles, even our forest-dwelling pal.

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Aerotitan sudamericanus: Air Nomads.

Size: Though it’s too fragmentary to definitely ascertain this animal’s size, its wingspan was probably at least 16.4 feet (5 meters) in width.

Time Period: The Early Maastrichtian Stage of the Late Cretaceous Period.

Locale: The Allen Formation of Argentina, a place that was also home to Willinakaqe and Austroraptor, the former of which has been covered on this blog.

Name: The generic name means ‘air titan,’ thanks to this animal’s large size and airborne lifestyle. The specific name means ‘of South America,’ because Aerotitan was found in South America.

I’ve mentioned that animals such as Quetzalcoatlus and Hatzegopteryx are macho pterosaurs. These huge creatures were very interesting and were probably also threatening. Here, I report a fairly new one, and the first confirmed azhdarchid from South America, Aerotitan.

This creature is known only from a rostrum, or the part of the head at the end of the beak. It was a toothless animal, and probably had a spearlike beak like its fellow azhdarchids. Its snout was very long and compressed transversely. The animal, like Hatzegopteryx and company, was a semi-terrestrial predator that lived much like a modern-day stork.

The real subject of this post isn’t about Aerotitan itself, it’s about it and the many other azhdarchid taxa that have been assigned. These animals all looked very similar, and are known from similar and fragmentary evidence. This makes me question just how many of these animals were distinct taxa. Here, I propose the theory that, since azhdarchids were such large flying creatures, they could fly from continent to continent and colonize the world without being very distinct taxa. Though this is a bit Paulian in a sense (and I don’t like lumping a bunch of taxa into a genus no matter how convenient it is), this large amount of taxa has always seemed a bit questionable to me. Though I could be wrong, it’s always a little bit tricky to assign taxa.

So, though Aerotitan seems like a distinct taxa, I’ve nursed my misgivings about it for a while now. The truth is, most of the azhdarchids can’t be definitely grouped outside of a single genus. Quetzalcoatlus and Hatzegopteryx, for example, aren’t distinct save for their locations on the globe. Though research might or might not prove me wrong, I can still have my opinion.

Note: I’m sorry that this post is so short. It’s hard to blog about such a poorly-known taxon.