Open Paleo

Xianshanosaurus

Lü et al., 2009 shyen-SHAHN-oh-SAWR-us

Named after Xianshan Hill near the fossil locality in the Ruyang Basin, Henan Province, China, combined with Greek 'sauros' meaning 'lizard'.

121.4–100.5 million years ago Aptian–Albian, Early Cretaceous
Early Cretaceous stages

Xianshanosaurus is a genus of sauropod dinosaur from the Early Cretaceous (Aptian-Albian) of the Ruyang Basin in Henan Province, China. Its type and only species is Xianshanosaurus shijiagouensis. It was described in 2009 by a team of paleontologists led by Lü Junchang. Xianshanosaurus may be a titanosaur, and Daxiatitan may be its closest relative, but its evolutionary relationships remain controversial.

Under dispute

Most analyses recover Xianshanosaurus within Titanosauria, usually as the sister of Daxiatitan just outside Lithostrotia (Mannion and colleagues, 2013; Upchurch and colleagues, 2015; Han and colleagues, 2024; Averianov and colleagues, 2025), and some implied-weights analyses place it within Lithostrotia (Mannion and colleagues, 2019). Gallina and colleagues (2021) instead recover it as a euhelopodid, with Huabeisaurus and Daxiatitan, and Moore and colleagues (2020) find it labile, recovering it in a non-neosauropod Euhelopodidae in their Bayesian analysis.

Diagnosis

  1. Elongated tooth with a distinct ridge on the lingual surface of the tooth crown.
  2. Neural spines of anterior caudal vertebrae plate-like with coarse areas on the middle portions of the anterior and posterior surfaces.
  3. Distinct fossae present on the anterolateral surface of the base of the prezygapophysis and the anterior surface of the base of the transverse process.
  4. Coracoid foramen located closely to the scapula-coracoid suture.
  5. Shallow concavity present on the proximal end of the dorsal ribs.

Species

Xianshanosaurus shijiagouensis Lü et al., 2009

Type species

Named for Shijiagou, the locality near Xian Mountain in Henan Province, China, where the holotype was found.

Holotype
KLR-07-62-3a, KLR-07-62-6, KLR-07-62-15, KLR-07-62-59, KLR-07-62-59-1 , Henan Geological Museum
Material
Ten naturally articulated anterior caudal vertebrae and one haemal arch, one nearly complete right coracoid, one complete left femur, several complete and incomplete dorsal ribs; one sauropod tooth attributed to the same individual.
Horizon
Haoling Formation, Aptian–Albian, Early Cretaceous , 121.4–100.5 million years ago
Locality
Shijiagou Quarry, Henan, China

References

  1. Lü, J.; Xu, L.; Jiang, X.; Jia, S.; Li, M.; Yuan, C.; Zhang, X.; Ji, Q. (2009). A preliminary report on the new dinosaurian fauna from the Cretaceous of the Ruyang Basin, Henan Province of central China. Journal of the Paleontological Society of Korea 25(1): 43-56.

    Named Xianshanosaurus and placed it provisionally in Neosauropoda, outside Titanosauridae.

    lü2009b
  2. Jones, B. (2026). The Princeton Encyclopedia of Dinosaurs: Sauropods. Princeton University Press.

    Source of the body length, mass, and hip height estimates.

    jones2026b
  3. Han, F.; Yang, L.; Lou, F.; Sullivan, C.; Xu, X.; Qiu, W.; Liu, H.; Yu, J.; Wu, R.; Ke, Y.; Xu, M.; Hu, J.; Lu, P. (2024). A new titanosaurian sauropod, Gandititan cavocaudatus gen. et sp. nov., from the Late Cretaceous of southern China. Journal of Systematic Palaeontology 22(1): 2293038. Informa UK Limited. doi:10.1080/14772019.2023.2293038

    Recovered Xianshanosaurus within Titanosauria as the sister taxon of Daxiatitan.

    han2024a
  4. D'Emic, M. D. (2012). The early evolution of titanosauriform sauropod dinosaurs. Zoological Journal of the Linnean Society 166: 624-671. doi:10.1111/j.1096-3642.2012.00853.x

    Referred Xianshanosaurus to Lithostrotia on the basis of a single character.

    d'emic2012b
  5. Mannion, P. D.; Upchurch, P.; Barnes, R. N.; Mateus, O. (2013). Osteology of the Late Jurassic Portuguese sauropod dinosaur Lusotitan atalaiensis (Macronaria) and the evolutionary history of basal titanosauriforms. Zoological Journal of the Linnean Society 168(1): 98-206. Oxford University Press (OUP). doi:10.1111/zoj.12029

    Recovered Xianshanosaurus just outside Lithostrotia, with Daxiatitan.

    mannion2013a
  6. Upchurch, P.; Mannion, P. D.; Taylor, M. P. (2015). The Anatomy and Phylogenetic Relationships of "Pelorosaurus" becklesii (Neosauropoda, Macronaria) from the Early Cretaceous of England. PLOS ONE 10(6): e0125819. Public Library of Science (PLoS). doi:10.1371/journal.pone.0125819

    Recovered Xianshanosaurus as a titanosaur in all analyses.

    upchurch2015a
  7. Mannion, P. D.; Upchurch, P.; Jin, X.; Zheng, W. (2019). New information on the Cretaceous sauropod dinosaurs of Zhejiang Province, China: impact on Laurasian titanosauriform phylogeny and biogeography. Royal Society Open Science 6(8): 191057. doi:10.1098/rsos.191057

    Recovered Xianshanosaurus with Daxiatitan just outside Lithostrotia under equal weights, and as a basal lithostrotian under implied weights.

    mannion2019b
  8. Gallina, P. A.; Canale, J. I.; Carballido, J. L. (2021). The Earliest Known Titanosaur Sauropod Dinosaur. Ameghiniana 58(1). Asociacion Paleontologica Argentina. doi:10.5710/amgh.20.08.2020.3376

    Recovered Xianshanosaurus as a euhelopodid, with Huabeisaurus and Daxiatitan.

    gallina2021a
  9. Moore, A. J.; Upchurch, P.; Barrett, P. M.; Clark, J. M.; Xu, X. (2020). Osteology of Klamelisaurus gobiensis (Dinosauria, Eusauropoda) and the evolutionary history of Middle-Late Jurassic Chinese sauropods. Journal of Systematic Palaeontology 18(16): 1299-1393. doi:10.1080/14772019.2020.1759706

    Found Xianshanosaurus labile, as a titanosaur or turiasaurian under equal weights, a lithostrotian under implied weights, and a non-neosauropod euhelopodid in the Bayesian analysis.

    moore2020a
  10. Averianov, A. O.; Sizov, A. V.; Grigoriev, D. V.; Kolchanov, V. V.; Skutschas, P. P. (2025). A sauropod Tengrisaurus starkovi from the Lower Cretaceous of Transbaikalia, Russia, and Asiatic origin of Titanosauria. Cretaceous Research 181: 106271. doi:10.1016/j.cretres.2025.106271

    Recovered Xianshanosaurus with Daxiatitan as the sister of Lithostrotia.

    averianov2025b