a genus of fossil amphibia of the true-vertebrate order Labyrinthodontia. Discovered by V. P. Amalitskii in the Upper Permian deposits on the Severnaia Dvina River.
The body of the Dvinosaurus was approximately a meter long; the skull was a flat, rounded triangle with large upturned orbits and widely separated nostrils. The Dvinosaurus retained external gills throughout its life; like the present-day axolotl, the Dvinosaurus was neotenic and led an aquatic life.
REFERENCESAmalitskii, V.P. Dvinosauridae. Petrograd, 1921. (Severo-Dvinskie raskopki prof. V. P. Amalitskogo, issue 1).
Bystrow, A. P. “Dvinosaurus als neotenische Form der Stegocephalen.” Acta Zoologica, 1938, vol. 19.