page_title: Dvinosaurus
section_title: History
hierarchical_section_title: Dvinosaurus / History and Description / History
caption_attribution_description: Italiano: Fossil of Dvinosaurus, an extinct amphibian- Took the picture at Museum of Paleontology, Tuebingen
context_page_description: Dvinosaurus is an extinct genus of amphibious temnospondyls localized to regions of western and central Russia during the Late Permian, approximately 265-254 million years ago. Its discovery was first noted in 1921 by Russian paleontologist Vladimir Prokhorovich Amalitskii in a posthumously published paper that documents the findings of a site in Russia's Arkhangelsk District. Its name is derived from the proximity of this site to the Northern Dvina River.
  Dvinosaurus is thought to have been a gill-breathing, fully-aquatic tetrapod, characterized by a large, triangular head, short limbs, and a long powerful tail. A typical individual could grow to be approximately 40 in in length.
  Within this genus, the number of documented species has varied over the years since its discovery. Prior to his untimely death, Amalitskii described three species, Dvinosaurus primus, Dvinosaurus secundus, and Dvinosaurus tertius. Upon further analysis, however, these three proposed species would be reclassified as solely D. primus as the latter two were found to be age-stages of the same species.
context_section_description: Following his death in 1917, Amalitskii's notes and initial observations of Dvinosaurus were transferred to the Paleontological Institute of the Russian Academy of Sciences. Over the course of the next 8 years, Prof. Petr Sushkin carried out a thorough analysis of these notes in order to provide the first description of Dvinosaurus. Later in the century, at a site near the small town of Vyazniki in western Russia, many more Dvinosaurus specimens were identified and analyzed by B.P. Vjuschkov and Mikhail Shishkin, who classified two new species of Dvinosaurus and added to the depiction of the genus as whole in the process. What follows is a summary and general description of their combined findings.
caption: D. primus skull
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