TY - JOUR

T1 - Chondrichthyan spines from the Famennian (Upper Devonian) of Russia

AU - Lebedev, Oleg

AU - Ivanov, Alexander O.

AU - Linkevich, Valeriy

N1 - Funding Information: The authors are grateful to V. Pazukhin (Institute of Geology, Ufa Scientific Centre, Ufa, Russia) for donation of the Uralian specimen to the Palaeontological Museum of the St. Petersburg State University, St. Petersburg, Russia, and to A. Kachalkin for presenting the specimen he discovered to the A.A. Borissiak Palaeontological Institute of the Russian Academy of Sciences, Moscow, Russia; to U. Toom (Tallinn University of Technology, Tallinn, Estonia) and O. Hampe (Museum für Naturkunde der Humboldt-Universität zu Berlin, Berlin, Germany) for providing the specimens for our studies and the photograph of the holotype; to S. Nilov (Institute of Earth Sciences, St. Petersburg State University) for microtomographic sections and reconstruction. We thank Michał Ginter (University of Warsaw, Poland) and an anonymous reviewer for their valuable comments and corrections. With the exception of Text-figs 6 and 9, S. Bagirov carried out the beautiful photography, and R. Rakitov kindly assisted during SEM imaging in the A.A. Borissiak Palaeontological Institute of the Russian Academy of Sciences, Moscow, Russia. The microtomographic research was performed at the Centre for X-ray Diffraction Studies of the Research Park of the St. Petersburg State University. This research was supported by the programme of the Presidium of the Russian Academy of Sciences “Organic World Evolution. Role and Influence of Planetary Processes”. The work is performed according to the Russian Governmental Program of Competitive Growth of Kazan Federal University.

PY - 2020

Y1 - 2020

N2 - Lebedev, O.A., Ivanov, A.O. and Linkevich, V.V. 2020. Chondrichthyan spines from the Famennian (Upper Devonian) of Russia. Acta Geologica Polonica, 70 (3), 339–362. Warszawa. Very rare chondrichthyan spines from the Famennian (Upper Devonian) of European Russia are referred here to ctenacanthiforms, euselachians and a chondrichthyan group of uncertain systematic position. Ctenacanthus Agassiz, 1837 is recorded from the lower and middle Famennian of the central and north-western parts of the area. Sculptospina makhlaevi Lebedev gen. et sp. nov. originates from the lower Famennian of the Lipetsk Region. The holotype of ‘Ctenacanthus’ jaekeli Gross, 1933 and a new specimen from the upper Famennian of the South Urals are shown to belong to the same taxon, which is transferred to Acondylacanthus St. John and Worthen, 1875. New specimens of Tuberospina nataliae Lebedev, 1995 from the upper Famennian of Central Russia are described in detail. The newly presented material increases our knowledge of the composition of Famennian marine assemblages from the East European Platform. It is suggested that these assemblages may be classified as chondrichthyan-dominated and dipnoan-dominated. Hypothetically, after the end-Devonian Hangenberg extinction event, which affected numerous secondary consumers in vertebrate communities, some chondrichthyan groups could have encroached to take advantage of previously occupied ecological niches. Ctenacanthus, as well as Acondylacanthus and Amelacanthus survived the end-Devonian mass extinction to continue into the Carboniferous.

AB - Lebedev, O.A., Ivanov, A.O. and Linkevich, V.V. 2020. Chondrichthyan spines from the Famennian (Upper Devonian) of Russia. Acta Geologica Polonica, 70 (3), 339–362. Warszawa. Very rare chondrichthyan spines from the Famennian (Upper Devonian) of European Russia are referred here to ctenacanthiforms, euselachians and a chondrichthyan group of uncertain systematic position. Ctenacanthus Agassiz, 1837 is recorded from the lower and middle Famennian of the central and north-western parts of the area. Sculptospina makhlaevi Lebedev gen. et sp. nov. originates from the lower Famennian of the Lipetsk Region. The holotype of ‘Ctenacanthus’ jaekeli Gross, 1933 and a new specimen from the upper Famennian of the South Urals are shown to belong to the same taxon, which is transferred to Acondylacanthus St. John and Worthen, 1875. New specimens of Tuberospina nataliae Lebedev, 1995 from the upper Famennian of Central Russia are described in detail. The newly presented material increases our knowledge of the composition of Famennian marine assemblages from the East European Platform. It is suggested that these assemblages may be classified as chondrichthyan-dominated and dipnoan-dominated. Hypothetically, after the end-Devonian Hangenberg extinction event, which affected numerous secondary consumers in vertebrate communities, some chondrichthyan groups could have encroached to take advantage of previously occupied ecological niches. Ctenacanthus, as well as Acondylacanthus and Amelacanthus survived the end-Devonian mass extinction to continue into the Carboniferous.

KW - Chondrichthyes

KW - Ctenacanthiformes

KW - Devonian

KW - Euselachii

KW - Famennian

KW - Fin spines

KW - Russia

UR - http://www.scopus.com/inward/record.url?scp=85095592902&partnerID=8YFLogxK

U2 - 10.24425/agp.2020.132255

DO - 10.24425/agp.2020.132255

M3 - Article

VL - 70

SP - 339

EP - 362

JO - Acta Geologica Polonica

JF - Acta Geologica Polonica

SN - 0001-5709

IS - 3

ER -