Azhdarcho restored (from bits and pieces)

Earlier
we looked at the neck and skull of Azhdarcho… Today we’ll put all the bits and pieces we know (from several individuals, unfortunately) to see what we get, following the Q. sp. bauplan (Fig. 1).

Figure 1. Azhdarcho to scale with more complete smaller Quetzalcoatlus specimen and in proportion to the bauplan of Q. sp. Note the robust femur and gracile humerus. These together with the small sternal complex and short distal wing elements indicate a flightless condition.

Figure 1. Azhdarcho to scale with more complete smaller Quetzalcoatlus specimen and in proportion to the bauplan of Q. sp. Note the robust femur and gracile humerus. These together with the small sternal complex and short distal wing elements indicate a flightless condition.

Azhdarcho lancicollis (Nesov 1984, Averianov 2010) is the namesake for the clade Azhdarchidae. This species is known from several individuals of various sizes and very few complete bones. That is why reconstructions of this genus are rare. This reconstruction is based on the more complete Q. sp., but about half as tall.

Given these limitations,
(no complete long bones), the femur appears to be more robust than in other azhdarchids, while the humerus is more gracile. Only in Huanhepterus is the femur so relatively short. The sternal complex is quite small, but with a deep cristospine, distinct from other azhdarchids. (Perhaps the rest of the sternal complex is missing.) Manual 4.4 was identified by Averianov, but it appears to be the distal portion of m4.3. The scale bars for the distal femur appear to be in error, or apply to a much larger individual (see Fig. 1).

The invisible aid in this reconstruction
is the observation that in nearly all post-Huanhepterus azhdarchids, the metacarpus, manual digit 4 and tibia are similar in length (Fig. 1), no matter how small or tall… probably to facilitate terrestrial locomotion.

Unfortunately,
not enough is known of Azhdarcho to add it to the LRT. So much has to be imagined.

References
Averianov AO 2010. The osteology of Azhdarcho lancicollis Nessov, 1984 (Pterosauria, Azhdarchidae) from the Late Cretaceous of Uzbekistan. Proceedings of the Zoological Institute of the Russian Academy of Sciences, 314(3): 246-317.
Nesov LA 1984. Upper Cretaceous pterosaurs and birds from Central Asia. Archived 17 March 2012 at the Wayback Machine. Paleontologicheskii Zhurnal, 1984(1), 47-57.

wiki/Azhdarcho

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