The new Chaoyangopterus is really a Jidapterus. Close, but no cigar.

It really pays to make reconstructions. And to analyze traits in a large data matrix.

 Not Chaoyangopterus, but Jidapterus.

Figure 1. Not Chaoyangopterus, but Jidapterus is LPM-R00076.

In 2010, Zhou reported on a complete but disarticulated skeleton of a stork-like pterosaur, a small azhdarchid they assigned to Chaoyangopterus. They reported, “LPM-R00076 lacks a pneumatic foramen on the proximal end of first wing phalanx that has been reported in Jidapterus edentus (LÜ et al. 2006a). Therefore, LPM-R00076 is identified as Chaoyangopterus zhangi on the basis of the similar skull shape and limb proportions.

Chaoyangopterus  (Zhou 2012)

Figure 2. Click to enlarge. Left: Jidapterus. Right: Chaoyangopterus. Middle: Chaoyangopterus (Zhou 2012, LPM (Liaoning Paleontological Museum)-R00076) nests closer to Jidapterus, but it’s close. All of the data available has been crappy at best. They are all closely related.

Phylogenetic analysis in the large reptile tree nests the new specimen firmly with Jidapterus. Nested between them adds three steps. Nested with Chaoyangopterus adds 18 steps. Sure would be nice to get better resolution on those photos.

Eopteranodontids and early azhdarchids are very similar in appearance, but the large (derived from Germanodactylus) vs. small (derived from Dorygnathus) sternal complex is a dead giveaway, among several other traits. Closeups of the jawtips would be nice. Feet are good lumpers and dividers.  I’d like to correct any and all mistakes.

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.

Zhou C-F 2010. New material of Chaoyangopterus (Pterosauria: Pterodactyloidea) from the Early Cretaceous Jiufotang Formation of western Liaoning, China. N. Jb. Geol. Paläont. Abh. 257/3, 341–350.

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