Orbitolina Morelensis Sp. Nov. from the Lower Cretaceous (Albian) Morelos Formation in the Huetamo region, Michoacán, Mexico

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Published: Jan 1, 1960
DOI: https://doi.org/10.22201/igl.05437652e.1960.0.6.94
Keywords:
Orbitolina, Lower Cretaceous, Michoacán

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Agustín Ayala-Castañares
Geology Institute, National Autonomous University of Mexico, Scientific Research Circuit S/N, Ciudad Universitaria, Coyoacán, 04510, CDMX, Mexico.

Abstract

A new species of the genus Orbitolina Orbigny, 1850, from sediments of the Morelos formation (Fries, 1956) near the town of Mal Paso, in the Huetamo region, Michoacán, is described and illustrated. The study was made using, to a great extent, the statistical method to obtain some constants, but the qualitative characters were also considered.
Orbitolina morelensis sp. nov. is a species very close to Orbtolina texana (Roemer), but it differs from it, among other characteristics, due to the smaller average diameter of the proloculus and embryonic apparatus, as well as presenting calcite microconcretions in the central zone and occasionally in the radial zone that until to date have not been observed in Orbitolina Texana (Roemer).

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How to Cite
Ayala-Castañares, A. (1960). Orbitolina Morelensis Sp. Nov. from the Lower Cretaceous (Albian) Morelos Formation in the Huetamo region, Michoacán, Mexico. Paleontología Mexicana, (6), 1–25. https://doi.org/10.22201/igl.05437652e.1960.0.6.94
Issue
No. 6 (1960): Orbitolina Morelensis Sp. Nov. from the Lower Cretaceous (Albian) Morelos Formation in the Huetamo region, Michoacán, Mexico
Section
Palaeozoology
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