Revision of the early tetrapod Obruchevichthys Vorobyeva, 1977 from the Frasnian (Upper Devonian) of the North-western East European Platform
Species composition of the genus Obruchevichthys Vorobyeva, 1977, previously based on two specimens from the Upper Frasnian (Upper Devonian) of Latvia and Leningrad Region of Russia is revised. The precise locality of the latter specimen was considered by the author of this taxon as unknown. Archives recently found in collection and field research in the presumable locality allowed the rediscovery of this important locality along the Sondala River (east of the Leningrad Region). This provenance is furthermore supported by spectrometric testing. Despite the presence of several subadult features hindering its attribution by earlier authors to a separate taxon, new observations on its morphology revealed that several characters of the material from Russia significantly differ from those of the type specimen that resulted in its attribution to a new genus and species Weberepeton sondalensis gen. et sp. nov. These differences mainly consist in a number of lower jaw characters, such as relative size of marginal teeth, development rate of the adsymphysial plate, orientation of the precoronoid fossa, and dermal ornamentation.
Unable to display preview. Download preview PDF.
- Blieck, A., Clément, G., Blom, H., Lelievre, H., Lukševičs, E., Streel, M., Thorez, J., and Young, G.C., The biostratigraphical and palaeogeographical framework of the earliest diversification of tetrapods (Late Devonian), in Devonian Events and Correlations, Becker, R.T. and Kirchgasser, W.T., Eds., Geol. Soc. London Spec. Publ., 2007, vol. 278, pp. 219–235.Google Scholar
- Bystrow, A.P. and Efremov, I.A. Benthosuchus sushkini Efremov—labirintodont iz eotriasa reki Sharzhengi (Benthosuchus sushkini Efremov—a labyrinthodont from the Eotriassic of the Sharzenga River), Trudy Paleontologicheskogo Instituta AN SSSR, 1940, vol. 10, pp. 1–152 (in Russian).Google Scholar
- Esin, D., Ginter, M., Ivanov, A., Lebedev, O., Lukševičs, E., Avkhimovich, V., Golubtsov, V., and Petukhova, L., Vertebrate correlation of the Upper Devonian and Lower Carboniferous on the East European Platform, Courier Forschungsinstitut Senckenberg, 2000, vol. 223, pp. 341–359.Google Scholar
- Jarvik, E., The Devonian tetrapod Ichthyostega, Fossils and Strata, 1996, vol. 40, pp. 1–213.Google Scholar
- Lukševičs, E., Ahlberg, P.E., Stinkulis, G., Vasiľkova, J., and Zupiņš, I., Frasnian vertebrate taphonomy and sedimentology of macrofossil concentrations from the Langsede Cliff, Latvia, Lethaia, 2011, vol. 45, pp. 356–370.Google Scholar
- Pander, C.H., Über die Saurodipterinen, Dendrodonten, Glyptolepiden und Cheirolepiden des devonischen Systems, St. Petersburg: Buchdrückerei der kaiserlichen Akademie der Wissenschaften, 1860, pp. III–IX + 1–89.Google Scholar
- Säve-Söberbergh, G., Preliminary note on Devonian stegocephalians from East Greenland, Meddelelser om Gronland, 1932, vol. 94, pp. 1–211.Google Scholar
- Shishkin, M.A., Morfologiya drevnikh zemnovodnykh i problemy evolyutsii nizshikh tetrapod (Morphology of Early Amphibians and Problems of Lower Tetrapod Evolution), Moscow: Nauka, 1973, pp. 5–260 (in Russian).Google Scholar
- Sorokin, V.S., Etapy razvitiya severo-zapada Russkoy platform vo franskom veke, (Stages of Development of the Northwestern Russian Platform in the Frasnian) Riga: Zinatne, 1978, pp. 5–282 (in Russian).Google Scholar
- Vorobyeva, E.I., Morfologiya i osobennosti evolyutsii kistepyorykh ryb (Morphology and nature of evolution of crossopterygian fishes), Trudy Paleontologischeskogo Instituta AN SSSR, 1977, vol. 163, pp. 1–239 (in Russian).Google Scholar