Abstract
The shell structure of the Early Cretaceous rhynchonellids from Crimea has not been previously studied. First data on the shell structure of Berriasian rhynchonellids from the family Praecyclothyrididae Makridin, 1964 from southwestern and central Crimea are presented. Sulcirhynchia semenovi (Moisseev, 1939), S. berriasensis (Lobacheva, 1980), S. gracilis (Lobacheva, 1977), Belbekella airgulensis Moisseev, 1939, B. mutabilis Lobacheva, 1983, B. minor Lobacheva, 1983 and partly Lamellaerhynchia rectimarginata (Smirnova, 1972) are studied. The shell wall of most species consists of three layers: external (finely or coarsely crystalline), fibrous, and prismatic layers. The layers are usually strongly recrystallized, especially external and prismatic layers. New fibers were formed by repeated dichotomy of ridges in different areas of the fibrous layer independently of the distance from the anterior margin.
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Smirnova, T.N., Rannemelovye brakhiopody (morfologiya, sistematika, filogeniya, znachenie dlya biostratigrafii i paleozoogeografii) (Early Cretaceous Brachiopods: Morphology, Systematics, Phylogeny, and Significance for Biostratigraphy and Paleozoogeography), Afanasjeva, G.A., Ed., Moscow: Nauka, 1984.
Smirnova, T.N. and Chen Xingyui, Shell structure of the Early Cretaceous (Berriasian-Barremian) Rhynchonellids from Dagestan, Paleontol. J., 2010, vol. 44, no. 4. pp. 395–398.
Smirnova, T.N., Two types of shell microstructure in the Early Cretaceous superfamily Rhynchonelloidea Gray, 1848, in Paleostrat-2011, Godichnoe sobranie sektsii paleontologii MOIP i moskovskogo otdeleniya paleontologicheskogo obshchestva, Moskva, 24–26 yanvarya 2011 g., Programma i tezisy dokladov, (Paleostrat-2011, Annual Meeting of the the Section of Paleontology of the Moscow Society of Naturalists and Moscow Division of the Paleontological Society, Moscow, January 24–26, 2011, Program and Abstracts), Moscow: Paleontol. Inst. Ross. Akad. Nauk, 2011, p. 63–64.
Smirnova, T.N., Early Cretaceous rhynchonellids of Dagestan: System, morphology, stratigraphic and paleobiogeographic significance, Paleontol. J., 2012, vol. 46, no. 11, pp. 1197–1296.
Williams, A., A history of skeletal secretion among articulate brachiopods, Lethaia, 1968, vol. 1, no. 3, pp. 268–287.
Williams, A., Comments of the growth of the shell of the articulate brachiopods, Paleozoic Perspectives: A Paleontological Tribute to G. Arthur Cooper, Dutro, J.T., Jr., Ed., Smithson. Contrib. Paleobiol., 1971a, no. 3, pp. 47–67.
Williams, A., Scanning electron microscopy of the calcareous skeleton of fossil and living Brachiopoda, Scanning Electron Microscopy: Systematic and Evolutionary Applications, Heywood, V.H., Ed., London-New York: Academic Press, 1971b, pp. 37–66.
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Original Russian Text © T.N. Smirnova, 2014, published in Paleontologicheskii Zhurnal, 2014, No. 1, pp. 42–48.
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Smirnova, T.N. First data on the shell structure of the Early Cretaceous (Berriasian) rhynchonellids from Crimea. Paleontol. J. 48, 41–46 (2014). https://doi.org/10.1134/S0031030114010134
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DOI: https://doi.org/10.1134/S0031030114010134