Editing Dinosaurus (section)

==History of study==

The holotype of ''Dinosaurus murchisonii'' was collected in a copper mine in the [[Orenburg Governorate]] of the [[Russian Empire]] during the 1840s.{{sfn|Eichwald|1848|p=6}} It was collected in two pieces, found on separate occasions. The director of the mine, Wagenheim von Qualen, initially identified the first piece as a plant fossil in a letter to Johann Fischer von Waldheim, but Fischer realized it was part of a skull and described it as a new species of ''Rhopalodon'', ''R. murchisonii'', in 1845.{{sfn|Baur|Case|1899|p=32}} In 1847, Fischer described the second piece and established a new genus, ''Dinosaurus'', for the species. In 1848, Eichwald recognized that the two specimens were not only from the same species, but fit together as parts of the same individual. He provisionally returned the species to ''Rhopalodon'', as he felt there were not enough differences yet identified to justify a second genus, and noted the existence of the similarly-named taxon [[Dinosauria]], named by [[Richard Owen]] only a few years prior, in 1842.{{sfn|Eichwald|1848|pp=7–8}}

Wagenheim von Qualen donated both specimens to the collection of [[Maximilian de Beauharnais, 3rd Duke of Leuchtenberg|Maximilian de Beuharnais]], [[Duke of Leuchtenberg]], and the originals have since been lost. However, casts of the specimens are housed in the [[Paleontological Institute, Russian Academy of Sciences]] under the catalog numbers PIN 296/1 and PIN 296/2.

In 1894, [[H. G. Seeley]] remarked that ''Cliorhizodon'', which is now regarded as a junior synonym of ''[[Syodon]]'',{{sfn|Kammerer|2011|p=263–264}} could not be distinguished from ''Dinosaurus''.{{sfn|Seeley|1894|p=670}} In 1954, [[Ivan Yefremov|Ivan Efremov]] synonymized ''Dinosaurus'' with ''[[Brithopus]]''. This has been followed by some other authors,{{sfn|Battail|Surkov|2003|p=97}} but Christian Kammerer has regarded ''Brithopus'', which is based on only a partial humerus, as a ''[[nomen dubium]]'', and as such did not regard ''Dinosaurus'' as synonymous with it.

In 2000, M. F. Ivakhnenko synonymized ''[[Phthinosuchus]]'' with ''Dinosaurus''.{{sfn|Ivakhnenko|2000|p=75}} As such, he classified ''Dinosaurus'' in the family Phthinosuchidae, which he grouped with [[Rubidgeinae|Rubidgeidae]]{{efn|Usually treated as a subfamily, [[Rubidgeinae]], within [[Gorgonopsia|Gorgonopidae]].{{sfn|Kammerer|2016}}}} in the superfamily Rubidgeoidea of the order Gorgonopia.{{sfn|Ivakhnenko|2002|p=58}} Kammerer has remarked that the limited anatomical information available for ''Dinosaurus'' makes it hard to confirm this proposed synonymy.{{sfn|Kammerer|2011|p=289}}