Levnesovia (lat.) - genus of herbivorous ornithopod dinosaurs of the superfamily Hadrosauroidea from the Cretaceous of Asia . The typical and only Levnesovia transoxiana species was named and described by the German paleontologist Hans-Dieter Sius and the Russian paleontologist Alexander Averyanov in 2009. The name of the genus was given in honor of the Soviet paleontologist Lev Aleksandrovich Nesov. The species name is given by the name of the historical region of Transoxania , located beyond the Amu Darya River, on the territory of which modern Uzbekistan is located [1] .
| † Levnesovia |
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| No rank : | Bilateral symmetrical |
| Infraclass : | Archosauromorphs |
| No rank : | Archosauriformes |
| Infrastructure : | † Ornithopods |
| Parvotryad : | † Iguanodonts |
| Superfamily : | † Hadrosavroids |
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Levnesovia Sues & Averianov, 2009 |
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| † Levnesovia transoxiana Sues & Averianov, 2009 |
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The holotype USNM 538191, which is the postorbital part of the skull roof with an almost full cranium, and additional material were found in the layers of the Bissect formation dated to the Middle - late Turonian , Kyzylkum desert , Navoi region , Uzbekistan.
Additional material: ZIN PH 1306/16 - fragment of the roof of the skull of an immature individual; ZIN PH 1307/16 - fragment of the roof of the skull of an adult; USNM538126 - partial skull box and skull roof; CCMGE 565/12457, 566/12457 and ZIN PH 306/16 - almost full skull boxes of adults; USNM 538121 - cranial box of an immature individual; many isolated skull bones and post-cranial bones in the collections of various museums in the world. All additional material comes from the same location and horizon. Cranial boxes and fragments of the roof of the skull are indistinguishable from the holotype, and all other material has no taxonomically significant differences, which allows us to attribute all additional material to one taxon [1] .
Levnesovia is a hadrosaroid iguanodont, which differs from the known non-hadrosaroid iguanodonts in the following ways: there is no connection between the external pterygoid bone and the zygomatic; a gravel-shaped predental bone with a slightly rounded front edge; there is no sub-hole; the opening of the arched bone is absent; crowns of a dentary tooth have one main crest and indistinct secondary crests (if any). Levnesovia differs from Bactrosaurus in the presence of a long sagittal crest on the parietal bones, the absence of a lacrimal process on the prefrontal bone, and the absence of club-shaped spinous processes of the dorsal vertebrae in adults; differs from Gilmoreosaurus by a shortened connection of the frontal bone with the edge of the orbit, an elongated diastema between the first dentary tooth and the predental bone (more than 1/5 of the length of the dentition) and an almost vertical coronal process of the dentary. From more advanced hadrosaroids, Levnesovia is distinguished by the absence of a well-developed ectopterygoid crest on the jawbone; the dentary dentition and the posterior edge of the dentary end at the apex of the coronoid process; the dental dentition is inclined lingually in the occlusal projection [1] .
Gregory S. Paul estimates the length of Levnesovia at 2 m and weight at 175 kg [2] .
To clarify the phylogenetic position, an analysis was performed using 138 characters for 34 taxa. Hypsilophodon was selected as an external group. As a result, we obtained the only strictly consensus tree [1] :
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| Probactrosaurus |
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| Equijubus |
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| Protohadros |
| | Hadrosauroidea |
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| Tanius |
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| Telmatosaurus |
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| Aralosaurus |
| | Hadrosauridae |
| Lambeosaurinae |
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| Hadrosaurinae |
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