Non-ammonoid cephalopods of the Early Permian Shakhtau reef (Republic of Bashkortostan, Russia)

A.Yu. Shchedukhin

Borissyak Paleontological Institute, Russian Academy of Sciences, Moscow, 117647 Russia

E-mail: aleksandrsheduhin@mail.ru

Received November 30, 2021

ORIGINAL ARTICLE

Full text PDF

DOI: 10.26907/2542-064X.2022.2.318-327

For citation: Shchedukhin A.Yu. Non-ammonoid cephalopods of the Early Permian Shakhtau reef (Republic of Bashkortostan, Russia). Uchenye Zapiski Kazanskogo Universiteta. Seriya Estestvennye Nauki, 2022, vol. 164, no. 2, pp. 318–327. doi: 10.26907/2542-064X.2022.2.318-327. (In Russian)

Abstract

This article presents the results of a study of new cephalopod collections from the Shakhtau quarry. The latter has so far been little explored as a separate locality of cephalopods: the first descriptions of several pseudorthoceratid species from the Shakhtau reef massif were made in the mid-20th century, only from the Artinskian part of it, and contained the lists of the numerous Asselian-Sakmarian nautilids, without descriptions; a more detailed study of the Shakhtau cephalopod complexes has been carried out relatively recently. In this study, two representatives of the order Pseudorthoceratida were recorded for the first time in the Asselian-Sakmarian deposits of the Shakhtau locality: Uralorthoceras tzwetaevae Shimansky and Kionoceras serenum Shimansky. Additionally, several forms of the order Nautilida were newly identified here: Gzheloceras uralense Ruzhencev et Shimansky, ?Temnocheilus sp. A; two new genera (Genus A and Genus B) from the family Rhiphaeoceratidae and two new forms related to the family Grypoceratidae (Genus C and Genus D), with an intricately dissected suture line. They may belong to a new family of the Permian nautilids. In the Asselian-Sakmarian community, they are both related to the Carboniferous and completely new species and genera of nautilids. The ratio of life forms brings the near-riff Asselian-Sakmarian community of the Shakhtau quarry closer to the similar Kazanian (Roadian) community from the Volga-Ural region. The results obtained are of great importance for understanding and reconstructing the evolutionary pathways of the Early Permian non-ammonoid cephalopods.

Keywords: Permian, Asselian, Sakmarian, Artinskian, Nautilida, Pseudorthoceratida, Rhiphaeoceratidae, Grypoceratidae, Temnocheilidae

Figure Captions

Fig. 1. Map of the Sterlitamak shikhans Shakhtau, Kushtau, and Tratau.

Fig. 2. Localities of the Shakh-Tau quarry (see [2], with updates).

Fig. 3. Asselian-Sakmarian pseudorthoceratid and rhiphaeoceratid cephalopods in the Shakhtau deposits: a – Kionoceras serenum Shimansky; b – Uralorthoceras tzwetaevae Shimansky; c – Gzheloceras uralense Ruzhencev et Shimansky; d – Rhiphaeoceratidae, Genus A; e – Rhiphaeoceratidae, Genus B. Scale bar: 1 cm.

Fig. 4. Asselian-Sakmarian cephalopods in the Shakhtau deposits: a – ?Temnocheilus sp. A; b – Grypoceratidae, Genus C; c – Grypoceratidae, Genus D. Scale bar: 1 cm.

References

1. Korolyuk I.K. Metody i rezul’taty izucheniya permskogo rifogennogo massiva Shakhtau (Bashkirskoe Priural’e) [Methods and Results of Studies of the Permian Reef Massif Shakhtau (Bashkirian Urals)]. Мoscow, Nauka, 1985. 112 p. (In Russian)
2. Mazaev A.V. Lower Permian gastropods of Shakhtau (Asselian-Sakmarian boundary beds, southern Cisuralia). Paleontol. J., 2019, vol. 53, no. 12, pp. 1237–1345. doi: 10.1134/S0031030119120025.
3. Leonova T.B., Shchedukhin A.Yu. Asselian-Sakmarian nautiloids of the Shakh-Tau reef (Bashkortostan). Paleontol. J., 2020, vol. 54, no. 10, pp. 1113–1134. doi: 10.1134/S0031030120100044.
4. Shchedukhin A.Yu., Leonova T.B. Late Artinskian nautiloids of the Shakh-Tau reef (Bashkortostan). Paleontol. J., 2020, vol. 54, no. 10, pp. 1135–1151. doi: 10.1134/S003103012010007X.
5. Shchedukhin A.Yu. Late Artinskian straight-shelled cephalopods of the Shakhtau, Bashkortostan region. In: Leonova T.B., Mitt V.V. (Eds.) Sovremennye problemy izucheniya golovonogikh mollyuskov. Morfologiya, sistematika, evolyutsiya, biostratigrafiya [Current Problems in Studying Cephalopods. Morphology, Taxonomy, Evolution, Biostratigraphy]. Moscow, PIN Ross. Akad. Nauk, 2021, no. 6, pp. 58–62. (In Russian)
6. Barskov I.S., Boiko M.S. Sakmarian (Early Permian) nautilids of the Shakhtau reef (Bashkortstan). In: Zolotoi vek rossiiskoi malakologii: Sb. tr. Vseros. nauch. konf., posv. 100-letiyu so dnya rozhd. prof. V.N. Shimanskogo [The Golden Age of Russian Malaсology: Proc. All-Russ. Conf. Dedicated to the 100th Birth Anniversary of Professor V.N. Shimansky]. Moscow, Saratov, PIN Ross. Akad. Nauk, 2016, pp. 207–211. (In Russian)
7. Ruzhentsev V.E., Shimansky V.N. Nizhnepermskie svernutye i sognutye nautiloidei Yuzhnogo Urala [Lower Permian Coiled and Curved Nautiloids of the Southern Urals]. Moscow, Izd. Akad. Nauk SSSR, 1954. 167 p. Tr. Paleontol. Inst., vol. 50. (In Russian)
8. Shimansky V.N. Pryamye nautiloidei i baktritoidei sakmarskogo i artinskogo yarusov yuzhnogo Urala [Sakmarian and Artinskian Straight-Shelled Nautiloids and Bactritoids of the Southern Urals]. Moscow, Izd. Akad. Nauk SSSR, 1954. 173 p. Tr. Paleontol. Inst., 1954, vol. 44. (In Russian)
9. Shimansky V.N. Kamennougol’nye Nautilida [Carboniferous Nautilida]. Moscow, Nauka, 1967. 258 p. Tr. Paleontol. Inst., vol. 115. (In Russian)
10. Shimansky V.N. Nautilida (izuchennost’, stratigraficheskoe i geograficheskoe rasprostranenie, etapy razvitiya) [Nautilida (Research, Stratigraphic and Geographic Distribution, Stages of Development)]. Moscow, Nauka, 1979. 68 p. Tr. Paleontol. Inst., vol. 170. (In Russian)
11. Zhuravleva F.A., Shimansky V.N. Osnovnye voprosy sistimatiki nautiloidei i rodstvennykh im grupp [Major Taxonomic Problems of Nautiloids and Related Groups]. Moscow, Izd. Akad. Nauk SSSR, 1961. 193 p. Tr. Paleontol. Inst., vol. 90. (In Russian)
12. Sobolev E.S. Morphology, system, and evolution of the Clydonautilacea (Nautiloidea). Paleontol. Zh., 1991, no. 4, pp. 42–51. (In Russian)
13. Shimansky V.N. Order Nautilida. In: Orlov Yu.A. (Ed.) Osnovy paleontologii [Principles of Paleontology]. Vol. 5: Mollusca – Cephalopoda I. Nautiloidea, Endocerotoidea, Actinoceratoidea, Bactritoidea, Ammonoidea (Agoniatitidae, Goniatitida, Clymeniida). Moscow, Izd. Akad. Nauk SSSR, 1962, pp. 115–154. (In Russian)
14. Miller A.K., Youngquist W. American Permian nautiloids. Geol. Soc. Am., Mem., 1949, vol. 41, pp. 1–218. (In Russian)

The content is available under the license Creative Commons Attribution 4.0 License.