[D] Xuwulong yueluni [sG] [T]
You, Li & Liu, W 2011
Cretaceous Early Aptian Albian
Ornithischia Ornithopoda Hadrosauridae
Xinminpu Group, Yujingzi Basin, Jinta County, Jiuquan area, Gansu Province, China
You, H., Li, D. & Liu, W. (2011) A new hadrosauriform dinosaur from the Early Cretaceous of Gansu Province, China. Acta Geologica Sinica (Eng.ed.) Vol 85 No. 1 pp. 51-57
A new basal hadrosauriform dinosaur, Xuwulong yueluni gen. et sp. nov., is reported based on an articulated specimen including a complete cranium, almost complete axial skeleton, and complete left pelvic girdle. The specimen is recovered from the Early Cretaceous Yujingzi Basin in the Jiuquan area, Gansu Province of northwestern China. Xuwulong is among the most basal members of hadrosauriform dinosaurs, and distinguished by its Sunique lower jaw in having a V-shaped rostral end of the dentary in lateral view and a mandibular articular surface which levels with mid-height of the dentary ramus, as well as an enlarged and downturned prepubic process. Including Xuwulong, three basal hadrosauriforms have been discovered from the Early Cretaceous Xinminpu Group in the Mazongshan area, making it an important area to study the origin and early evolution of duck-billed dinosaurs.
“Xu-wu” is the courtesy name (a tradition in China to have another name when a person grows into an adult in order to avoid his/her given name to be called by younger persons) of professor Wang Yue-lun (1903-1981), a pioneer geologist devoted to the geological survey in Gansu Province. In 1943, he esthablished Gansu geological exhibition room, the precursor of the Gansu Geological Museum, which reopened in 2010 with new exhibits of Gansu dinosaurs. – “Yue-lun” is the givenname of Professor Wang Yue-lun (1903-1981)
Gansu Geological Museum GSGM_F00001 (field number: GSJB06-17-04, an articulated skeleton including skull, lower jaw, axial skeleton lacking only the distal caudals, left pelvic girdle,a nd bundles of ossified epaxial tendons. The cranium was originally articulated with the postcranial skeleton, but detached for further preperation. The postcrania is still surrounded by matrix, only its left side is exposed.
Locality and horizon
Yujingzi Basin, Jinta County, Jiuquan area, Gansu Province. Xinminpu Group, late Early Cretaceous (Aptian-Albian)
A basal hadrosauriform dinosaur distinguished by having the following unique combination of features: a non-downturned ans V-shaped rostral and of the dentary in lateral view, with the tip lying slightly below the mid-height of the dentary ramus; mandibular articular surface of the same level as the mid-height of the dentary ramus; and downturned, enlarged prepubic process. The lacrimal of het new taxon is similar to that of more derived basal hadrosauriforms (Equijubus and Probactrosaurus and hadrosaurids in having a longer ventral than dorsal edge (Norman, 2002; You et al., 2003a). In lateral view the maxila of the new taxon has a low, triangular profile with a long rostral portion, similar to the condition in less derived basal hadrosauriforms (Iguanodon, Ouranosaurus, Altirhinus and Jinzhousaurus) (Taquet, 1976; Norman, 1980, 1998; Wang & Xu, 2001) and unlike the almost isosceles triangular profile in more derived basal hadrosauriforms (Equijubus and Probactrosaurus) and hadrosaurids (Norman, 2002; You et al., 2003a)