Geologicheskii Vestnik

The data on findings of fish remains in the Lower Permian of Bashkirian shikhans are rare. The tooth whorl of helicoprionid Shaktauites seywi was described from the Sakmarian Sterlitamakian Regional Stage of Shakhtau shikhan. The remains of elasmobranch chondrichthyans such as symmoriids, jalodontid, anachronistid and synechodontid neoselachians were mentioned from the Sakmarian and Artinskian deposits of Toratau shikhan. The diverse isolated exoskeletal elements (teeth, scales and denticles) of chondrichthyan and actinopterygian fishes have been found in the deposits of Sterlitamakian Regional Stage (Sakmarian) and Sargian Regional Stage (Artinskian) of Lower Permian from the Toratau shikhan (South Urals, Republic of Bashkortostan). Chondrichthyan fishes are represented by symmoriids Stethacanthulus decorus and Kungurodus obliquus, jalodontid Adamantina sp., anachronistid Cooleyella fordi, synechodontid Synechodus antiquus. The teeth of Adamantina differ from the teeth of known species, and probably belong to a new species. The preservation of actinopterygian microremains does not allow to determine exactly the taxa. The ichthyoassemblage includes the taxa of chondrichthyans Stethacanthulus and Adamantina widely distributed in the Carboniferous and Permian of various regions of the world. But the taxa occurred in the narrow stratigraphic interval are presented in the assemblage. Symmoriid Kungurodus obliquus has been found in the Asselian — Kungurian of Lower Permian in the South Urals and in the Artinskian of Kazakhstan Cis-Urals. The oldest synechodontid Synechodus antiquus is known only from the Sakmarian — Artinskian of South Urals, and a holotype originated from the Artinskian Sargian Regional Stage of the Toratau shikhan.

Lower Permian, South Urals, shikhans

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