Abstract
The hybocrinid crinoid Trecrinus schmidti gen. et sp. nov. is described from the Middle Ordovician (Uhaku Regional Stage, Darriwilian) of the lower reaches of the Volkhov River. Three long arms in the A, D and C radii, and a low cup with a flattened base without a stem are the main characteristics of the new genus. Morphology of the new genus emphasizes the similarities and differences in the morphogenetic capabilities of the hybocrinid lineages, which simultaneously developed on the Baltica and Laurentia paleocontinents, separated from each other in Ordovician. In the pronounced tiering of the Valim benthic community, this new genus occupied the lowest bottom stage.
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REFERENCES
Ivantsov, A. Yu. and Mel’nikova, L. M., The Azeri, Lasnamagi, and Uhaku Ordovician Horizons of the Leningrad Region and Their Trilobite and Ostracode Faunas, Stratigr. Geol. Correl., 2003, vol. 11, no. 4, pp. 332– 347.
Männil, R.M., New representatives of the genus Hoplocrinus from the Middle Ordovician o Estonia, Uchen. Zap. Tartus. Gos. Univ., 1959, no. 75, pp. 82–97.
Rozhnov, S.V., Hybocrinea, a new subclass of crinoids, Dokl. Akad. Nauk SSSR, 1985a, vol. 280, no. 4, pp. 1012–1015.
Rozhnov, S.V., Morphology, symmetry, and systematic position of hybocrinid crinoids, Paleontol. Zh., 1985b, no. 2, pp. 4–16.
Rozhnov, S.V., Arms versus Brachioles: Morphogenetic basis of similarity and differences of food-gathering appendages of pelmatozoan Echinoderms, Paleontol. J., 2016, vol. 50, no. 14, pp. 1598–1609.
Rozhnov, S.V., New data on perittocrinids and hybocrinids (Crinoidea, Echinodermata) from the Middle Ordovician of the Baltic Region, Ann. Paléontol., 2007, vol. 93, no. 4, pp. 261–276.
Rozhnov, S.V., Development of the trophic structure of Vendian and Early Paleozoic marine communities, Paleontol. J., 2009, vol. 43, no. 11, pp. 1364–1367.
Rozhnov, S.V., Sibling echinoderm taxa on isolated Ordovician continents: problem of center of origin, Bull. Geosci., 2010, vol. 85, pp. 671–678.
Schmidt, F., Ober einige neue und wenig bekannte baltisch-silurischen Petrefacten. Miscellanea Silurica II, Mem. Acad. Sci. St.-Petersbourg, Ser. VII, 1874, vol. 21, no. 11, pp. 1–48
Sprinkle, J. and Moore, R.C., Hybocrinida, Treatise on Invertebrate Paleontology. Part T. Echinodermata 2, Moore, R.C., Ed., Boulder, Lawrence: Geol. Soc. America, Univ. Kansas Press, 1978, pp. 405–407.
ACKNOWLEDGMENTS
The authors are grateful to I.O. Pakhomov for the specimen of the new genus donated to the collection of the Paleontological Institute of the Russian Academy of Sciences; S.V. Bagirov (Paleontological Institute of the Russian Academy of Sciences) for the photographs taken.
Funding
This work was carried out with the financial support of the Russian Science Foundation grant no. 19-14-00346. This paper is a contribution to Project 653 of the International Geosciences Program “The Beginning of the Great Ordovician Diversification Event”.
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Translated by S. Nikolaeva
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Semenov, N.K., Terentyev, S.S., Mirantsev, G.V. et al. A New Hybocrinid Genus (Echinodermata, Crinoidea) from the Middle Ordovician of Ladoga Glint on the Volkhov River. Paleontol. J. 55, 54–63 (2021). https://doi.org/10.1134/S0031030121010123
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DOI: https://doi.org/10.1134/S0031030121010123