Re-Revision of Yixianopterus
Yixianopterus is an Early Cretaceous mid-sized pterosaur
known from a near complete roadkill fossil – with some artistic additions to what little remained of the skull area to make it look more complete and thus raise its potential market value.
Jiang, Zhang, Cheng and Wang 2021 revised
earlier understandings (by Lü et al 2006) by showing which areas were modified or enhanced during preparation. The 2021 authors also provided closeups of the rostrum (Fig 2) and foot (Fig 3). The 2021 authors nested Yixianopterus with basal ornithocheirids like Haopterus and Mimodactylus (reviewed yesterday).
LIkewise, until yesterday, the LPT confirmed that nesting.
But the Yixianopterus size was off, and so was its relative torso length, prompting additional study. Yixianopterus (Fig 1) was too big to be a basal ornithocheirid despite its toothy rostrum and tiny pes.
Figure 1. A reconstruction of Yixianopterus with a new reconstruction of the small pes. The smaller, more colorful skeleton belongs to a unidentified member of the genus Changchengopterus, the closest relative to Yixianopterus in the LPT.
” data-medium-file=”https://pterosaurheresies.wordpress.com/wp-content/uploads/2025/04/yixianopterus588-1.jpg?w=277″ data-large-file=”https://pterosaurheresies.wordpress.com/wp-content/uploads/2025/04/yixianopterus588-1.jpg?w=584″ class=”size-full wp-image-92240″ src=”https://pterosaurheresies.wordpress.com/wp-content/uploads/2025/04/yixianopterus588-1.jpg” alt=”Figure 1. A reconstruction of Yixianopterus with a new reconstruction of the small pes. The smaller, more colorful skeleton belongs to a unidentified member of the genus Changchengopterus, the closest relative to Yixianopterus in the LPT.” width=”584″ height=”632″ srcset=”https://pterosaurheresies.wordpress.com/wp-content/uploads/2025/04/yixianopterus588-1.jpg?w=584&h=632 584w, https://pterosaurheresies.wordpress.com/wp-content/uploads/2025/04/yixianopterus588-1.jpg?w=139&h=150 139w, https://pterosaurheresies.wordpress.com/wp-content/uploads/2025/04/yixianopterus588-1.jpg?w=277&h=300 277w, https://pterosaurheresies.wordpress.com/wp-content/uploads/2025/04/yixianopterus588-1.jpg 588w” sizes=”(max-width: 584px) 100vw, 584px” />
Figure 1. A reconstruction of Yixianopterus with a new reconstruction of the small pes. The smaller, more colorful skeleton belongs to a unidentified member of the genus Changchengopterus, the closest relative to Yixianopterus in the LPT.
Revised tracings from Jiang, Zhang, Cheng and Wang
(Figs 2, 3) moved Yixianopterus over to Changchengopterus (Fig 1), a smaller taxon basal to wukongopterids and darwinopterids.
Like these taxa, Yixianopterus independently evolved a pterodactyloid-grade morphology. See the large pterosaur tree (LPT, 264 taxa).
That brings the convergence of pterodactyloid-grade pterosaur clades to a total of x5*. Academics do not recognize more than one pterodactyloid-grade clade. Three such clades were first reported by Peters 2007. Workers continue to omit pertinent taxa.
* 1. Ctenochasmatids. 2. Azhdarchids. 3. Pterodactylids. 4. Hamipterids 5. Yixianopterus
Figure 2. Yixianopterus jaw tips. DGS colors added here.
” data-medium-file=”https://pterosaurheresies.wordpress.com/wp-content/uploads/2025/04/yixianopterus.jaw_.tips588.gif?w=300″ data-large-file=”https://pterosaurheresies.wordpress.com/wp-content/uploads/2025/04/yixianopterus.jaw_.tips588.gif?w=584″ class=”size-full wp-image-92233″ src=”https://pterosaurheresies.wordpress.com/wp-content/uploads/2025/04/yixianopterus.jaw_.tips588.gif” alt=”Figure 2. Yixianopterus jaw tips. DGS colors added here. ” width=”584″ height=”274″ srcset=”https://pterosaurheresies.wordpress.com/wp-content/uploads/2025/04/yixianopterus.jaw_.tips588.gif?w=584&h=274 584w, https://pterosaurheresies.wordpress.com/wp-content/uploads/2025/04/yixianopterus.jaw_.tips588.gif?w=150&h=70 150w, https://pterosaurheresies.wordpress.com/wp-content/uploads/2025/04/yixianopterus.jaw_.tips588.gif?w=300&h=141 300w, https://pterosaurheresies.wordpress.com/wp-content/uploads/2025/04/yixianopterus.jaw_.tips588.gif 588w” sizes=”(max-width: 584px) 100vw, 584px” />
Figure 2. Yixianopterus jaw tips. DGS colors added here. Note how left and right teeth are so aligned the broken upper ones can barely be distinguished from the complete lower teeth. Here the palate is visible.
The rostrum and pes
of Yixianopterus (Figs 2, 3) were key to understanding this taxon better.
Details matter. Reconstructions matter. Adding taxa matters.
Figure 3. The pes of Yixianopterus in situ and reconstructed using DGS methods.
” data-medium-file=”https://pterosaurheresies.wordpress.com/wp-content/uploads/2025/04/yixianopterus.pes588.jpg?w=300″ data-large-file=”https://pterosaurheresies.wordpress.com/wp-content/uploads/2025/04/yixianopterus.pes588.jpg?w=584″ class=”size-full wp-image-92235″ src=”https://pterosaurheresies.wordpress.com/wp-content/uploads/2025/04/yixianopterus.pes588.jpg” alt=”Figure 3. The pes of Yixianopterus in situ and reconstructed using DGS methods. ” width=”584″ height=”328″ srcset=”https://pterosaurheresies.wordpress.com/wp-content/uploads/2025/04/yixianopterus.pes588.jpg?w=584&h=328 584w, https://pterosaurheresies.wordpress.com/wp-content/uploads/2025/04/yixianopterus.pes588.jpg?w=150&h=84 150w, https://pterosaurheresies.wordpress.com/wp-content/uploads/2025/04/yixianopterus.pes588.jpg?w=300&h=168 300w, https://pterosaurheresies.wordpress.com/wp-content/uploads/2025/04/yixianopterus.pes588.jpg 588w” sizes=”(max-width: 584px) 100vw, 584px” />
Figure 3. The pes of Yixianopterus in situ and reconstructed using DGS methods. Note the cracked mt1 (dark red).
You’ll note many differences
between Yixianopterus (Fig 1) and the ChinaX specimen of Changchengopterus (Fig 1) as one evolved from the other. Even so, the LPT had enough data to lump these two together among 260+ competing candidates. Relatively few pterosaurs have pedal digit 4 longer than 1–3 as measured from the heel (Fig 3).
Key note: The LPT did not omit the ChinaX specimen of Changchengopterus from its inclusion set. That mattered in this case.
References
Jiang S-X, Zhang X-J, Cheng X and Wang X-L 2021. A new pteranodontoid pterosaur forelimb from the upper Yixian Formation, with a revision of Yixianopterus jingangshanensis. Vertebrata Pal-Asiatica 59:81–94.
Lü J, Ji S, Yuan C, Gao Y, Sun Z and Ji Q 2006. New pterodactyloid pterosaur from the Lower Cretaceous Yixian Formation of Western Liaoning. In J. Lü, Y. Kobayashi, D. Huang, Y.-N. Lee (eds.), Papers from the 2005 Heyuan International Dinosaur Symposium. Geological Publishing House, Beijing 195-203.
Peters D 2007. The origin and radiation of the Pterosauria. In D. Hone ed. Flugsaurier. The Wellnhofer pterosaur meeting, 2007, Munich, Germany. p. 27.
wiki/Yixianopterus
wiki/Changchengopterus
Source: https://pterosaurheresies.wordpress.com/2025/04/04/re-revision-of-yixianopterus/
