Mandschurosaurus laosensis " Hoffet, 1944

Manitkoon, Sita, Deesri, Uthumporn, Warapeang, Prapasiri, Nonsrirach, Thanit & Chanthasit, Phornphen, 2023, Ornithischian dinosaurs in Southeast Asia: a review with palaeobiogeographic implications, Fossil Record 26 (1), pp. 1-25 : 1

" Mandschurosaurus laosensis " Hoffet, 1944

Material.

unnumbered specimen consists of vertebrae, ilium, and femora.

Locality and age.

Muong Phalane, Savannakhet Province of Laos; Grès Supérieurs Formation (≈ the Khok Kruat Formation), Aptian-Albian.

Previous study.

Mandschurosaurus was the first dinosaur named from China, its material collected from the Late Cretaceous Yuliangze Formation (Maastrichtian) in Heilongjiang (Amur) River area between China and Russia ( Godefroit et al. 2011). It was initially referred to the genus " Trachodon " Trachodon amurense ( Riabinin 1925), but was later re-assigned in 1930 to a new genus as Mandschurosaurus amurensis ( Godefroit et al. 2011). M. amurensis is a large hadrosaurid (duck-billed dinosaurs), based on a poorly preserved and incomplete skeleton, and is often considered as a nomen dubium ( Horner et al. 2004). Hoffet described the Laotian ornithopod material as " Mandschurosaurus laosensis " ( Hoffet 1944), which was considered Late Cretaceous (Senonian) in age ( Buffetaut 1991). However, some palaeontologists consider " M. laosensis " a nomen dubium ( Buffetaut 1991; Horner et al. 2004). " M. laosensis " is potentially a non-hadrosaurid iguanodontian, such as Siamodon , Ratchasimasaurus , and Sirindhorna from rocks of the same age in Thailand. Hoffet also suggested that another ilium which is more robust than " M. laosensis ", indicated the presence of a second taxon ( Buffetaut 1991; Allain et al. 1999).