Giant Chinese Cretaceous Anurognathid
Figure 1. Click to enlarge. The Anurognathidae to scale. The Chinese anurognathid is the tall one in the middle.
This is a different take on an older story.
Most anurognathids are the size of sparrows. Some rise to the size of robins and jays. So such sizes are very common among flying creatures.
Most anurognathids and proto-anurognathids lived during the Late Triassic to Late Jurassic, a time of great diversity, but not great size, in pterosaur history.
There are two exceptions to these patterns.
A partial skeleton of a pterosaur from Mexico, “Dimorphodon” weintraubi, nests with anurognathids. Other anurognathids would not have stood as tall as its knees. Living during the Early to Early Middle Jurassic, D. weintraubi is also one of the oldest and most primitive anurognathids.
Figure 2. Click for more info. The IVPP embryo scaled to an adult size (based on matching the egg to the pelvic opening diameter, along with various views of the skeleton and an egg and hatchling.
Twice as tall as the Mexican pterosaur is an closely related unnamed Chinese anurognathid (Fig. 2). This Early Cretaceous pterosaur had longer metacarpals than any other anurognathid. It retained the narrow premaxilla of its dimorphodontid forebearers. It also retained a relatively long neck. At present this taxon is only known from its egg and embryo. The adult size is figured by multiplying the embryo eight times, as in other pterosaur embryo/parent combinations we know of, like Pterodaustro.
Formerly considered an ornithocheirid with a short skull, we know from other embryos that ornithocheirid embryos did not have a short skull. DGS and a phylogenetic analysis revealed the identity of this embryo.
Now the interesting thing about this giant anurognathid is the embryo is very nearly the size of all other adult anurognathids (Fig. 1). That fact should not have removed the possibility that the embryo was a possible anurognathid, yet it did. If someone else would like to include an accurate reconstruction of this specimen and add the data to a phylogenetic analysis that would go a long way to validating or invalidating the present hypothesis, that would be great.
As always, I encourage readers to see specimens, make observations and come to your own conclusions. Test. Test. And test again.
Evidence and support in the form of nexus, pdf and jpeg files will be sent to all who request additional data.
References
Wang X-L and Zhou Z 2004. Palaeontology: pterosaur embryo from the Early Cretaceous. Nature 429: 623.
2012-11-25 20:02:12
Source: http://pterosaurheresies.wordpress.com/2012/11/25/giant-chinese-cretaceous-anurognathid/
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