Nanningosaurus (lat.) - genus of herbivorous ornithopod dinosaurs of the superfamily Hadrosauroidea from the Cretaceous of Asia . The type and only species Nanningosaurus dashiensis was named and described by a group of Chinese paleontologists led by Mo Jingyu in 2007. The name of the genus is given by the name of the city district of Nanning , where the remains were discovered. The species name is given by the name of the suburb of Nanning - Dashi (translated from Chinese means "large stone"), where dinosaur remains were discovered [1] .
| † Nanningosaurus |
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| No rank : | Bilateral symmetrical |
| Infraclass : | Archosauromorphs |
| No rank : | Archosauriformes |
| Infrastructure : | † Ornithopods |
| Parvotryad : | † Iguanodonts |
| Superfamily : | † Hadrosavroids |
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Nanningosaurus Mo et al. , 2007 |
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† Nanningosaurus dashiensis
Mo et al. , 2007 |
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The holotype NHMG8142 and paratype NHMG8143 were discovered in 1991 in the layers of the Nalong basin dating from the Upper Cretaceous , Guangxi Zhuang Autonomous Region , China .
The holotype is a dissected incomplete skeleton consisting of relatively complete right and left jaw bones, left tooth and scaly bones, the lower part of the right square bone, incomplete main occipital bone, one isolated dentary tooth, one cervical vertebra, incomplete left shoulder blade, incomplete left and the right humerus, relatively complete left sciatic bone, full of the left femur and left and right tibia. Paratype is a relatively complete right jawbone [1] .
Nanningosaurus differs from other hadrosaurids in a unique combination of primitive and advanced features: a high, pointed dorsal process of the jawbone with a reduced zygomatic process and a pronounced facet of the lacrimal bone; the thin humerus has a low, rounded deltopectoral crest; a transversely wide mandibular condyle of a square bone has a weakly developed near-square notch; the dentary tooth in the middle has one sinuous main crest, as well as one secondary; relatively few dental alveoli; the body of the sciatic bone is straight along almost its entire length, but at the distal end, the bone bends dorsally and expands in front of the sciatic foot [1] .
Gregory Paul estimated the length of the Nanningosaurus at 7.5 meters, and the mass at 2.5 tons [2] .
To clarify the phylogenetic position of Nanningosaurus , a data set was used from a 2004 study by David Norman [3] . The final matrix contained 105 characters for 20 taxa. In the resulting consent tree, for the majority of Nanningosaurus it is positioned as a basal lambeosaurin in a polytomy with a parasavrolophus and a cytosaurus . The authors note that the systematic position of Nanningosaurus as a basal lambeosaurin is approximate, since the specimen is not fully preserved [1] .
In subsequent phylogenetic studies, Nanningosaurus is already positioned as a basal hadrosauride outside the hadrosaurid family [4] [5] [6] [7] .
Cladogram based on a 2014 study by Xing and colleagues (strong consensus tree):
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| Ouranosaurus |
| | Hadrosauriformes |
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| Jinzhousaurus |
| | Hadrosauroidea | |
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