Wednesday, August 10, 2022

[Paleontology • 2022] Reappraisal of the largest ctenochasmatid Moganopterus zhuiana et al. 2012 (Pterosauria: Ctenochasmatidae)


Moganopterus zhuiana Lü et al., 2012 

in Gao, Jiang, Xu, et al., 2022. 

Moganopterus zhuiana Lü et al., 2012 was erected as a member of the Boreopteridae, which was questioned by different researchers shortly after the publication. Although the new assignment to the Ctenochasmatidae is widely accepted by pterosaur researchers, some characteristics still require a detailed description. Here, the holotype of this taxon is restudied, and some ambiguous characteristics are re-identified. The diagnosis of this taxon has been revised as the following: a large ctenochasmatid pterosaur, which can be distinguished from other members of this clade by a single autapomorphy: an elongated rod-like parietal crest that extends posterodorsally, forming an angle of about 15° with the ventral margin of the skull. This taxon can be further distinguished from other ctenochasmatids on the basis of the following combination of characteristics: straight occlusal surfaces of the upper and low jaws; presence of a low premaxillary crest confined anterior to the nasoantorbital fenestra; rostrum about two thirds of the skull length; nasoantorbital fenestra occupying slightly more than 20% of the skull length; about 100 slender teeth; and a mid-cervical length/width ratio of about 7. The wingspan of M. zhuiana has been re-estimated according to a simple regression equation for wingspan versus skull length in ctenochasmatids. It confirms that M. zhuiana, although smaller than previous thought, is still the largest known ctenochasmatid. When comparing the sizes of ctenochasmatids in the Jurassic and Cretaceous, ctenochasmatids showed a rough tendency to increase their sizes.

Key words: Liaoning, Jiufotang Formation, Moganopterus zhuiana, largest ctenochasmatid


Photographs and reconstruction of the holotype of Moganopterus zhuiana (HGM 41HIII-0419) from Jianchang, Liaoning
A. slab A; B. slab B; C. the reconstruction of the upper and lower jaws.



GAO Dian-Song, JIANG Shun-Xing, XU Li, CHENG Xin, YANG Li-Li, JIA Song-Hai and WANG Xiao-Lin. 2022. Reappraisal of the largest ctenochasmatid Moganopterus zhuiana Lü et al., 2012. VERTEBRATA PALASIATICA. 60(3); 197-211. vertpala.ac.cn/EN/10.19615/j.cnki.2096-9899.220111
 DOI: 10.19615/j.cnki.2096-9899.220111
http://www.vertpala.ac.cn/EN/2096-9899/home.shtml

   

摘要:朱氏莫干翼龙(Moganopterus zhuiana)由吕君昌等于2012年建立,并将其归入北方翼龙科(Boreopteridae), 这一分类在发表后不久就受到了不同研究者的质疑。之后,尽管关于莫干翼龙归入梳颌翼龙科(Ctenochasmatidae)的观点已被大部分翼龙研究者所接受,但是很多特征还需要详细的描述。通过对朱氏莫干翼龙的正型标本进行详细观察,对一些较为模糊的特征进行了重新确认。将其鉴定特征修改为:一种大型的梳颌翼龙类成员,具有一个与其他成员不同的自有裔征——一长棍状额骨嵴向后背侧延伸,并与头骨腹面形成15°夹角。同时莫干翼龙还具有以下的特征组合可以区别于其他梳颌翼龙类成员:平直的上下颌咬合面;低矮的前上颌骨嵴位于鼻眶前孔之前;吻端约占头骨长度的2/3; 鼻眶前孔占头骨长度略大于20%; 100枚细长的牙齿;中部颈椎的长宽比约为7。依据梳颌翼龙类翼展和头骨长度的线性关系,重新推测了莫干翼龙的翼展。新的推测结果证实,虽然比最初推测的小了很多,但莫干翼龙仍然是已知的个体最大的梳颌翼龙类成员。对比侏罗纪和白垩纪的梳颌翼龙类,这一种类的体型大致存在一个增大的趋势。

关键词: 辽宁, 九佛堂组, 朱氏莫干翼龙, 最大的梳颌翼龙类

Lü Junchang; Pu Hanyong; Xu Li; Wu Yanhua; Wei Xuefang (2012). "Largest Toothed Pterosaur Skull from the Early Cretaceous Yixian Formation of Western Liaoning, China, with Comments On the Family Boreopteridae". Acta Geologica Sinica. 86 (2): 287–293. DOI: 10.1111/j.1755-6724.2012.00658.x