Redescription of the dorsal vertebrae of the mamenchisaurid sauropod Xinjiangtitan shanshanesis Wu et al. 2013

ABSTRACT

The dorsal vertebrae of Xinjiangtitan shanshanesis (SSV12001) from the Late Jurassic Qigu Formation of Xinjiang Uygur Autonomous Region, China, are redescribed based on the further exposure and preparation of the holotype. As a mamenchisaurid sauropod dinosaur, Xinjiangtitan shanshanesis displays a unique combination of autapomorphic and plesiomorphic features, such as the presences of both lateral spinopostzygapophyseal laminae (L.SPOL) and medial spinopostzygapophyseal lamina (M.SPOL) in dorsal vertebrae and a shallow intralaminar fossa (SPOL-F) between the L.SPOL and M.SPOL; anterior spinodiapophyseal laminae (A.SPDL), posterior spinodiapophyseal laminae (P.SPDL) and middle spinodiapophyseal lamina (M.SPDL) in dorsals 3–5; bifurcated anterior and middle dorsal neural spines with the median tubercle and the triangular lateral processes. Phylogenetic analysis and morphological comparison show that Xinjiangtitan shanshanesis probably shares a close relationship with Hudiesaurus and Mamenchisaurus and provide new information for future taxonomic revision of the mamenchisaurids.

KEYWORDS:

• Xinjiangtitan shanshanesis
• dorsal vertebrae
• late Jurassic
• Qigu Formation
• Xinjiang

Acknowledgments

For their hospitality and access to specimens in their care, we thank the Shanshan Geological Museum. We wish to thank Gansu Sinian Dinosaur Culture Communication Co. Ltd. for their field assistance and the preparation of the specimen. We are grateful to Dr Lü Junchang, Wang YM, Yang JT, Li LF, Zhang QN and Ren XX for all of their assistance. Fieldwork funding was provided by the Rescue Excavation Project of Dinosaur Fossils in Shanshan, Xinjiang. HLY is supported by the Strategic Priority Research Program of the Chinese Academy of Sciences (XDB26000000) and the National Natural Science Foundation of China (Grants No. 42288201, 41872021 and 41472020).

Disclosure statement

No potential conflict of interest was reported by the author(s).