A new most ancient Permian Inoceramus-like bivalve of the genus Aphanaia Koninck from northeastern Asia

© 2015, Pleiades Publishing, Ltd. The most ancient representative of Permian Inoceramus-like bivalves, Aphanaia kletzi sp. nov., from the Upper Sakmarian of the Western Verkhoyansk Region (northeastern Asia) is described. It is established for the first time that the first kolymiids appeared in the northeastern Asian basins in the latter half of the Sakmarian rather than at the end of the Artinskian. The age of the record is reliably dated by the ammonoid genera Uraloceras and Neoshumardites

Permian ammonoids of the Okhotsk Region, Northeast Asia

© 2015, Pleiades Publishing, Ltd. Beds with ammonoids are recognized as a result of the study of goniatitids and prolecanitids from the Nyut, Khuren, and Ayan-Yuryakh in the Okhotsk Region. Beds with Neopronorites tenkensis, assigned to the Upper Artinskian Substage, correspond to the upper part of the Echian Horizon of the Verkhoyansk Region. Beds with Paragastrioceras–Baraioceras characterize the middle part of the Kungurian Stage and correlate with the upper sunhorizon of the Tumarian Horizon of the Verkhoyansk Region. Beds with Sverdrupites harkeri correspond to a biostratigraphic subdivision with the same name widely distributed in the Vekhoyansk-Kolyma Region and assigned to the Roadian Stage. The new species Neopronorites tenkensis is described

New data on the composition and evolution of the Permian superfamily popanocerataceae (Ammonoidea)

The evolution of the superfamily Popanocerataceae is studied. The nominotypical family Popanoceratidae includes two subfamilies (Popanoceratinae and Pamiropopanoceratinae). The study of the most recent finds of Roadian ammonoids allowed the establishment of a new stage of active morphogenesis in the family Mongoloceratidae, which includes the new genus Biarmiceras, combining characters connecting the two families of the Popanocerataceae. Five species are described: Biarmiceras tumarense (Ruzhencev), B. subtumarense (Andrianov), B. esaulovae sp. nov., B. kremeshkense sp. nov., and B. barskovi sp. nov. from the Kungurian-Roadian of northeastern Russia and the Kazanian of the Volga-Urals Region. Copyright © 2005 by MAIK "Nauka/Interperiodica" (Russia)

New records of the Late Carboniferous ammonoid genus Eoshumardites in the Kolyma–Omolon Region, and notes on the evolution of Eoshumarditidae

© 2016, Pleiades Publishing, Ltd.A new species, Eoshumardites popowi Kutygin sp. nov., is described from the Upper Carboniferous of the upper reaches of the Paren’ River in the Gizhiga Province of the Kolyma–Omolon Region. The ontogeny of the sutural and shell morphology of the new species is described. In the level of sutural organization, E. popowi occupies an intermediate position between E. lenensis (Popow) and E. sublenensis Klets. It has been suggested that Eoshumardites evolved from the genus Syngastrioceras rather than Aktubites and, on this basis, a new monotypic endemic family, Eoshumarditidae, has been proposed. This family existed in the Kasimovian synchronously with members of the family Parashumarditidae

New data on the structure and age of the terminal Permian strata in the South Verkhoyansk region (northeastern Asia)

© 2015.We present new data on the structure and age of the upper Permian strata in the basin of the Setorym River (tributary of the Vostochnaya Khandyga River) in the South Verkhoyansk region, represented by the Imtachan Formation and the lower part of the Nekuchan Formation. Based on the new findings of bivalve fossils from the Intomodesma costatum Zone, as well as on the study of carbon isotopes in the shells and carbon isotopes of the organic matter of the host mudstones, we have for the first time proved the completeness of the Permian section. The detailed description of the contact between the Imtachan and Nekuchan Formations bears evidence for a certain continuity of the lithologic characteristics of the sandstones. The sharp lithologic contact between the formations reflects not a regional sedimentation hiatus but a shift of depositional settings from the upper parts of a delta to the deep shelf, caused by forced marine transgression. It is concluded that there was no long-term hiatus between the accumulation of the Imtachan and Nekuchan Formations. Images of the most characteristic species of bivalves and crinoids from the Imtachan Formation are presented

Permian ammonoids of the Okhotsk Region, Northeast Asia

© 2015, Pleiades Publishing, Ltd. Beds with ammonoids are recognized as a result of the study of goniatitids and prolecanitids from the Nyut, Khuren, and Ayan-Yuryakh in the Okhotsk Region. Beds with Neopronorites tenkensis, assigned to the Upper Artinskian Substage, correspond to the upper part of the Echian Horizon of the Verkhoyansk Region. Beds with Paragastrioceras–Baraioceras characterize the middle part of the Kungurian Stage and correlate with the upper sunhorizon of the Tumarian Horizon of the Verkhoyansk Region. Beds with Sverdrupites harkeri correspond to a biostratigraphic subdivision with the same name widely distributed in the Vekhoyansk-Kolyma Region and assigned to the Roadian Stage. The new species Neopronorites tenkensis is described

Permian ammonoids of the Okhotsk Region, Northeast Asia

© 2015, Pleiades Publishing, Ltd. Beds with ammonoids are recognized as a result of the study of goniatitids and prolecanitids from the Nyut, Khuren, and Ayan-Yuryakh in the Okhotsk Region. Beds with Neopronorites tenkensis, assigned to the Upper Artinskian Substage, correspond to the upper part of the Echian Horizon of the Verkhoyansk Region. Beds with Paragastrioceras–Baraioceras characterize the middle part of the Kungurian Stage and correlate with the upper sunhorizon of the Tumarian Horizon of the Verkhoyansk Region. Beds with Sverdrupites harkeri correspond to a biostratigraphic subdivision with the same name widely distributed in the Vekhoyansk-Kolyma Region and assigned to the Roadian Stage. The new species Neopronorites tenkensis is described

A new most ancient Permian Inoceramus-like bivalve of the genus Aphanaia Koninck from northeastern Asia

© 2015, Pleiades Publishing, Ltd. The most ancient representative of Permian Inoceramus-like bivalves, Aphanaia kletzi sp. nov., from the Upper Sakmarian of the Western Verkhoyansk Region (northeastern Asia) is described. It is established for the first time that the first kolymiids appeared in the northeastern Asian basins in the latter half of the Sakmarian rather than at the end of the Artinskian. The age of the record is reliably dated by the ammonoid genera Uraloceras and Neoshumardites

A new most ancient Permian Inoceramus-like bivalve of the genus Aphanaia Koninck from northeastern Asia

© 2015, Pleiades Publishing, Ltd. The most ancient representative of Permian Inoceramus-like bivalves, Aphanaia kletzi sp. nov., from the Upper Sakmarian of the Western Verkhoyansk Region (northeastern Asia) is described. It is established for the first time that the first kolymiids appeared in the northeastern Asian basins in the latter half of the Sakmarian rather than at the end of the Artinskian. The age of the record is reliably dated by the ammonoid genera Uraloceras and Neoshumardites

Permian ammonoids of the Okhotsk Region, Northeast Asia

© 2015, Pleiades Publishing, Ltd. Beds with ammonoids are recognized as a result of the study of goniatitids and prolecanitids from the Nyut, Khuren, and Ayan-Yuryakh in the Okhotsk Region. Beds with Neopronorites tenkensis, assigned to the Upper Artinskian Substage, correspond to the upper part of the Echian Horizon of the Verkhoyansk Region. Beds with Paragastrioceras–Baraioceras characterize the middle part of the Kungurian Stage and correlate with the upper sunhorizon of the Tumarian Horizon of the Verkhoyansk Region. Beds with Sverdrupites harkeri correspond to a biostratigraphic subdivision with the same name widely distributed in the Vekhoyansk-Kolyma Region and assigned to the Roadian Stage. The new species Neopronorites tenkensis is described