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Jianchangnathus; Temporal range: Middle Jurassic, 160 Ma PreꞒ Ꞓ O S D C P T J K Pg N ↓
	Holotype, Paleozoological Museum of China
Scientific classification
Domain:	Eukaryota
Kingdom:	Animalia
Phylum:	Chordata
Order:	†Pterosauria
Family:	†Rhamphorhynchidae
Subfamily:	†Scaphognathinae
Genus:	†Jianchangnathus; Cheng et al., 2012
Species:	†J. robustus
Binomial name
	†Jianchangnathus robustus; Cheng et al, 2012

Jianchangnathus is an extinct genus of basal pterosaur from the Middle Jurassic Tiaojishan Formation of northeastern China.^[1]

Naming

Jianchangnathus was first described and named by Cheng Xin, Wang Xiaolin, Jiang Shunxing and Alexander W.A. Kellner in 2012 and the type species is Jianchangnathus robustus. The generic name combines a reference to Jianchang County with a Greek γνάθος, gnathos, "jaw". The specific name means "robust" in Latin.^[1]

Jianchangnathus was initially described based on a single fossil skeleton, holotype IVPP V16866, recovered near Linglongta, in Jianchang County. The second specimen, PMOL-AP00028, consisting of a partially articulated skull and fragments of postcranial skeleton of a subadult individual, was described in 2014.^[2]

Description

Autapomorphies of Jiangchangnathus include: a convex top margin of the lower jaw; a large front branch of the jugal; and the first three pairs of teeth of the lower jaws pointing strongly forwards. Its describers found it to share several features with Scaphognathus, including a high front end of the lower jaws, a pear-shaped lower temporal fenestra with the broad end below and teeth in the maxilla of the upper jaw that have a space equal to that of three toothsockets between them.^[1] Additionally, undescribed fossils of a pterosaur referred to Jianchangnathus suggest that the color of its pycnofibers was brown.^[3]

Phylogeny

Jianchangnathus was assigned by the describers to the Scaphognathidae by the describing authors,^[1] which was corroborated by later phylogenetic analyses which included this taxon.^[4]^[5]

References

^ ^a ^b ^c ^d Xin Cheng; Xiaolin Wang; Shunxing Jiang; Alexander W.A. Kellner (2012). "A new scaphognathid pterosaur from western Liaoning, China". Historical Biology. 24: 101–111. doi:10.1080/08912963.2011.635423. S2CID 128539358.
^ Chang-Fu Zhou (2014). "Cranial Morphology of a Scaphognathus-Like Pterosaur, Jianchangnathus robustus, Based on a New Fossil from the Tiaojishan Formation of Western Liaoning, China". Journal of Vertebrate Paleontology. 34 (3): 597–605. doi:10.1080/02724634.2013.812100.
^ Li, Q., J.A. Clarke, K.-Q. Gao, C.-F. Zhou, Q. Meng, D. Li, L. D'Alba, and M.D. Shawkey. 2014. Melanosome evolution indicates a key physiological shift within feathered dinosaurs. Nature 507: 350-353.
^ Wei, X.; Pêgas, R. V.; Shen, C.; Guo, Y.; Ma, W.; Sun, D.; Zhou, X. (2021). "Sinomacrops bondei, a new anurognathid pterosaur from the Jurassic of China and comments on the group". PeerJ. 9: e11161. doi:10.7717/peerj.11161. PMC 8019321. PMID 33850665.
^ Natalia Jagielska; Michael O’Sullivan; Gregory F. Funston; et al. (February 2022). "A skeleton from the Middle Jurassic of Scotland illuminates an earlier origin of large pterosaurs". Current Biology. 32: 1–8. doi:10.1016/J.CUB.2022.01.073. ISSN 0960-9822. Wikidata Q110984418.