The vertebrate microremains from the Wenlock (lower Silurian) to the Lower Lochkovian (Lower Devonian) of the Ufa Amphitheatre, on the western slope of the Central Urals, have been studied. This investigation discusses vertebrate taxonomy and biostratigraphy, with an emphasis on the agnathan groups Thelodonti, Heterostraci, Osteostraci, and Anaspida. The thelodont species identified in the region include Paralogania martinssoni (Gross), Phlebolepis elegans Pander, Thelodus laevis (Pander), Thelodus carinatus (Pander), Thelodus parvidens Agassiz, Thelodus sculptilis Gross, Thelodus trilobatus (Hoppe), Turinia pagei (Powrie), Boreania minima Karatajūtė-Talimaa, and Talivalia elongata (Karatajūtė-Talimaa). Representatives of Heterostraci – Eriptychiiformes with Oniscolepis Pander, and Traquairaspidiformes with ‘Traquairaspis’ sp. – are briefly discussed along with recently described cyathaspidid heterostracans (Archegonaspis lindstroemi Kiaer, Archegonaspis integra (Kunth), Cyathaspis alexanderi Märss, and Cyathaspis alexanderi? Märss). Osteostracans comprise Tremataspis schmidti Rohon, Tremataspis rohoni Robertson, Thyestes? sp. ind., Procephalaspis sp. ind., Tahulaspis ordinata Märss, Afanassieva et Blom and Tahulaspis praevia Märss, Afanassieva et Blom, the latter two being assigned to a new family, Tahulaspididae fam. nov. A few birkeniid anaspids (Schidiosteus mustelensis Pander, Septentrionia mucronata? Blom, Märss et Miller, and Liivilepis curvata Blom, Märss et Miller) have also been included to bring together all Silurian and Lower Devonian agnathans of the Ufa Amphitheatre in a single publication. Vertebrate distribution data have been used to determine the age of the strata and correlate the beds with those of the East Baltic. A reversed succession of vertebrate distribution was discovered in a section on the southern bank of Mikhailovsk Pond, and the recurrence of the bonebed complex was detected in the Tabuska Hill section (right bank of the River Ufa).
Blom, H., Märss, T. and Miller, G. C. 2001. Silurian and earliest Devonian birkeniid anaspids from the Northern Hemisphere. Earth and Environmental Transactions of the Royal Society of Edinburgh, 92(3), 263–323.
https://doi.org/10.1017/S0263593300000250
Chekhovich, P. A. 2007. Карбонатные платформы в ордовикско-силурийских окраинных и эпиконтинентальных бассейнах Северной Евразии. Седиментологические и тектонические аспекты эволюции (Carbonate platforms in the Ordovician–Silurian marginal and epicontinental basins of northern Eurasia. Sedimentological and tectonic aspects of evolution). Summary of doctoral dissertation. M. V. Lomonosov Moscow State University, Moscow.
Chekhovich, P. A. and Zhivkovich, A. E. 2024. Ordovician–Silurian carbonate platforms on the western slope of the Urals: conventional model revised. Paleontological Journal, 58(S4), S445–S464.
http://dx.doi.org/10.1134/S0031030124601798
Chekhovich, P. A., Zhivkovich, A. E. and Medvedovskaya, N. I. 1994. Изотопно-углеродная летопись силура и нижнего девона в опорных разрезах на Среднем Урале (Carbon isotope record of the Silurian and Lower Devonian in reference sections in the Middle Urals). Доклады Академии наук, 338, 514–516.
Denison, R. H. 1947. The exoskeleton of Tremataspis. American Journal of Science, 245(6), 338–365.
https://doi.org/10.2475/ajs.245.6.337
Gross, W. 1967. Über Thelodontier-Schuppen. Palaeontographica, Abteilung A, 127, 1–67.
Kaljo, D., Martma, T., Märss, T., Nestor, V.-K. and Viira, V. 2022. A bio- and chemostratigraphic search for the Mid-Ludfordian Carbon Isotope Excursion interval in the Ludlow of the Ohesaare core, Estonia. Estonian Journal of Earth Sciences, 71(1), 44–60.
https://doi.org/10.3176/earth.2022.04
Karatajūtė-Talimaa, V. 1978. Силурийские и девонские телодонты СССР и Шпицбергена (Silurian and Devonian Thelodonts of the USSR and Spitsbergen). Mokslas, Vilnius.
Karatajūtė-Talimaa, V. 1985. Телодонты подьемненской свиты (нижний девон, жедин) Северной Земли и их корреляционное значение (Thelodonts of the Podyomnaya Formation (Lower Devonian, Gedinnian) of Severnaya Zemlya and their correlative importance). Geologija, 6, 50–60.
Lindström, G. 1895. On remains of a Cyathaspis from the Silurian strata of Gotland. Kungliga Svenska Vetenskapsakademiens Handlingar, 21, 1–15.
Märss, T. 1986. Силурийские позвоночные Эстонии и Западной Латвии (Silurian Vertebrates of Estonia and West Latvia). Valgus, Tallinn.
http://www.digar.ee/id/nlib-digar:649668
Märss, T. 1989. Vertebrates. National Museum of Wales. Geological Series, 9, 284−289.
Märss, T. 1992. Vertebrate history in the late Silurian. Proceedings of the Estonian Academy of Sciences. Geology, 41(4), 205–214.
https://doi.org/10.3176/geol.1992.4.05
Märss, T. 1997. Vertebrates of the Přidoli and Silurian–Devonian boundary beds in Europe. Modern Geology, 21(1), 17–41.
Märss, T. 2001. Andreolepis (Actinopterygii) in the upper Silurian of northern Eurasia. Proceedings of the Estonian Academy of Sciences. Geology, 50(3), 174–189.
https://doi.org/10.3176/geol.2001.3.03
Märss, T. 2003. Paralogania from the Rootsiküla (Wenlock) and Paadla (Ludlow) stages of Estonia. Proceedings of the Estonian Academy of Sciences. Geology, 52(2), 98–112.
https://doi.org/10.3176/geol.2003.2.03
Märss, T. 2011. Siluri selgroogsed – ühe rühma arengulugu. (Silurian vertebrates – the evolutionary history of a group). In Teadusmõte Eestis (VI). Elu- ja maateadused (Scientific Thought in Estonia (VI). Life and Earth Sciences) (Parmasto, E., Laisk, A. and Kaljo, D., eds), Eesti Teaduste Akadeemia Kirjastus, Tallinn, 117–124.
Märss, T. 2019. Silurian cyathaspidid heterostracans of northern Eurasia. Estonian Journal of Earth Sciences, 68(3), 113–146.
https://doi.org/10.3176/earth.2019.11
Märss, T. and Karatajūtė-Talimaa, V. 2009. Late Silurian–Early Devonian tessellated heterostracan Oniscolepis Pander, 1856 from the East Baltic and North Timan. Estonian Journal of Earth Sciences, 58(1), 43–62.
http://dx.doi.org/10.3176/earth.2009.1.05
Märss, T. and Männik, P. 2013. Revision of Silurian vertebrate biozones and their correlation with the conodont succession. Estonian Journal of Earth Sciences, 62(4), 181–204.
https://doi.org/10.3176/earth.2013.15
Märss, T. and Miller, C. G. 2004. Thelodonts and distribution of associated conodonts from the Llandovery–lowermost Lochkovian of the Welsh Borderland. Palaeontology, 47(5), 1211–1265.
https://doi.org/10.1111/j.0031-0239.2004.00409.x
Märss, T. and Ritchie, A. 1997. Articulated thelodonts (Agnatha) of Scotland. Earth and Environmental Science Transactions of The Royal Society of Edinburgh, 88(3), 143−195.
https://doi.org/10.1017/S026359330000691X
Märss, T., Turner, S. and Karatajūte-Talimaa, V. 2007. Handbook of Paleoichthyology: “Agnatha” II: Thelodonti, Vol. 1B. Verlag Dr. Friedrich Pfeil, München.
Märss, T., Afanassieva, O. and Blom, H. 2014. Biodiversity of the Silurian osteostracans of the East Baltic. Earth and Environmental Science Transactions of The Royal Society of Edinburgh, 105(2), 73–148.
https://doi.org/10.1017/S1755691014000218
Modzalevskaya, T. and Märss, T. 1991. О возрасте подошвы гребенского горизонта Урала (On the age of the lower boundary of the Greben Regional Stage of the Urals). Proceedings of the Estonian Academy of Sciences. Geology, 40(3), 100–103.
https://doi.org/10.3176/geol.1991.3.03
Patrunov, D. K. and Shurygina, M. V. 2002. Силур и ранний девон в Уфимском Амфитеатре (Silurian and Early Devonian in the Ufa Amphitheatre). Litosfera, 2, 96–111.
Schultze, H.-P. and Märss, T. 2004. Revisiting Lophosteus Pander 1856, a primitive osteichthyan. In The Gross Symposium 2: Advances in Palaeoichthyology(Lukševičs, E., ed.). Acta Universitatis Latviensis, 679, 57–78.
Shujskij, V. P. 1981. Фациально-литологические особенности верхнесилурийских и нижнедевонских рифов западного склона Среднего Урала (Facial-lithological peculiarities of the upper Silurian and Lower Devonian reefs on the western slope of the Central Urals). In Биостратиграфия и фауна среднего палеозоя Урала (Biostratigraphy and Fauna of the Middle Palaeozoic of the Urals) (Sapel′nikov, V. P. and Chuvashov, B. I., eds). Уральский научный центр Академии наук СССР, Свердловск, 96–110.
Shurygina, M. V., Breivel’, M. G., Breivel’, I. A., Zenkova, G. G., Militsina, V. S. and Yanet, F. E. 1981. Пржидольский ярус на Северном и Среднем Урале (The Přidoli Series in the Northern and the Central Urals). In Биостратиграфия и фауна среднего палеозоя Урала (Biostratigraphy and Fauna of the Middle Palaeozoic of the Urals) (Sapel’nikov, V. P. and Chuvashov, B. I., eds). Уральский научный центр Академии наук СССР, Свердловск, 55–73.
Turner, S. 1984. Studies of Palaeozoic Thelodonti (Craniata: Agnatha). Unpublished PhD thesis. University of Newcastle upon Tyne, England.
Valiukevičius, J. 1992. First articulated Poracanthodes from the Lower Devonian of Severnaya Zemlya. In Fossils as Living Animals (Kurik, E., ed.).Academia, Tallinn, 193–213.
Viira, V. and Einasto, R. 2003. Wenlock–Ludlow boundary beds and conodonts of Saaremaa Island, Estonia. Proceedings of the Estonian Academy of Sciences. Geology, 52(4), 213–238.
http://dx.doi.org/10.3176/geol.2003.4.03
Zhivkovich, A. E. and Chekhovich, P. A. 1985. Палеозойские формации и тектоника Уфимского амфитеатра (Palaeozoic Formations and Tectonics of the Ufa Amphitheatre). Наука, Москва.
Zhivkovich, A. E. and Goreva, N. V. 1976. Стратиграфия пограничных отложений силура и девона западного склона Среднего Урала (Stratigraphy of the Silurian and Devonian boundary beds of western slope of the Central Urals). Известия Академии наук СССР. Серия Геологическая, 7, 70–83.
Zhivkovich, A. E., Chekhovich, P. A. and Märss, T. 1990. Late Silurian and earliest Devonian vertebrate microfossils of the Ufimian circus on the western Urals. Ichthyolith Issues: News and Views on Palaeozoic Vertebrate Microfossils, 3, 22.
