Baotianmansaurus
Named for the Baotianman National Nature Reserve in Henan Province, China, where the fossils were found, combined with Greek 'sauros' meaning 'lizard'.
Baotianmansaurus is an extinct genus of somphospondylian sauropod. Its fossils were discovered in the Late Cretaceous Gaogou Formation of Henan Province, China. The type and only species is B. henanensis — named after the province in which it was found.
Under dispute
Placed at Somphospondyli incertae sedis. Its position within Somphospondyli is genuinely contested: the describing paper (Zhang and colleagues, 2009) assigned it only to Titanosauriformes, declining to resolve its position within Titanosauria; D'Emic (2012) considered it to bear euhelopodid (non-titanosaurian somphospondylan) features; and the most recent dedicated analysis (Han and colleagues, 2024) recovers it within Titanosauria in an eastern-Asian clade with Andesaurus, Huabeisaurus, Dongyangosaurus and others. Somphospondyli is the least-inclusive clade all these hypotheses accept.
Diagnosis
- Transverse process of dorsal vertebra supported by four laminae (ppdl, pcdl, aspdl, pspdl), differing from all other sauropods whose transverse processes are supported by three laminae.
- Dorsal portion of the anterior centroparapophyseal lamina is bifurcated, with a small branch extending to the ventral surface of the prezygapophysis.
- Posterior centrodiapophyseal lamina is thin, nearly vertical, and plate-like, not forked at its ventral end.
- Postzygodiapophyseal lamina undeveloped, not reaching the top of the diapophysis.
- Anterior dorsal ribs apneumatic with a large concavity on the posterior surface of the proximal end, lacking a pneumatic foramen near the proximal end.
- Anterior caudal vertebra much shorter than wide, amphicoelous, with suboval articular ends.
Species
Baotianmansaurus henanensis Zhang et al., 2009
Type species
Named for Henan Province in China, where the fossil remains were discovered.
- Holotype
- 41H III-0200 , Henan Geological Museum
- Material
- Incomplete anterior dorsal vertebra (3rd), nearly complete mid-posterior dorsal vertebra (5th), five dorsal ribs, one and a half sacral vertebrae, one incomplete anterior caudal vertebra, portion of distal scapula, unidentified bone fragments.
- Horizon
- Xiaguan Formation, Turonian–Campanian, Late Cretaceous , 93.9–72.2 million years ago
- Locality
- Baotianman Nature Reserve, Henan, China
References
-
Zhang, X.; Lü, J.; Xu, L.; Li, J.; Yang, L.; Hu, W.; Jia, S.; Ji, Q.; Zhang, C. (2009). A New Sauropod Dinosaur from the Late Cretaceous Gaogou Formation of Nanyang, Henan Province. Acta Geologica Sinica (English Edition) 83(2): 212-221. Wiley. doi:10.1111/j.1755-6724.2009.00032.x
Describing paper; assigned Baotianmansaurus to Titanosauriformes by comparison, declining to resolve its position within Titanosauria.
zhang2009a -
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
Indicated euhelopodid (non-titanosaurian somphospondylan) affinities for Baotianmansaurus.
d'emic2012b -
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 Baotianmansaurus within Titanosauria, in an eastern-Asian non-lithostrotian clade with Andesaurus, Huabeisaurus and others.
han2024a -
Wang, D. Y.; Cao, X. Q.; Zhao, H. Y.; Cao, M. Z.; Fu, G. H.; Yan, F. C.; Qiang, W. G.; Wang, Y. Q. (2013). Discovery of invertebrate zoolite in the Xiaguan Formation of Xiaguan-Gaoqiu Basin, Henan, China, and its importance for stratigraphic subdivision comparison. Acta Geologica Sinica 87(8): 1049-1058.
Established the Xiaguan Formation at formation rank for the red beds the describing paper calls the Gaogou Formation.
wang2013c