Taxonomy
Original description: Diagnosis- Eoglobigerlna with a low spiral, consisting of two whorls. The first whorl comprises 3 to 5½ chambers and the final whorl contains 4 chambers. Wall thin, porous.
Description - Test small, low, its height approximately one-half the diameter. Spiral, formed by two whorls. The final whorl is two or three times higher than the first and consists of 4 rapidly increasing chambers which are slightly compressed along their height. The first whorl consists of 3 to 5½ chambers. Sutures between chambers weakly depressed, straight; those between the chambers of the first whorl sometimes slightly oblique. Aperture single, small, rounded, rimmed by a. narrow, weakly expressed lip. Wall thin, radiate, finely porous. Surface smooth, shiny or matte.
Entries in the Catalog of original descriptions: Globigerina (Eoglobigerina) balakhmatovae
Emended description:
Character matrix
test outline: | Lobate | chamber arrangement: | Trochospiral | edge view: | Spiroconvex | aperture: | Umbilical |
sp chamber shape: | Globular | coiling axis: | Low | periphery: | N/A | aperture border: | N/A |
umb chbr shape: | Globular | umbilicus: | Narrow | periph margin shape: | Broadly rounded | accessory apertures: | None |
spiral sutures: | Weakly depressed | umb depth: | Shallow | wall texture: | Finely pustulose | shell porosity: | Microperforate: <1µm |
umbilical or test sutures: | Weakly depressed | final-whorl chambers: | 4-4 | N.B. These characters are used for advanced search. N/A - not applicable |
Geological Range:
Last occurrence (top): within Early Kimmeridgian Substage (152.20-154.78Ma, top in Kimmeridgian stage). Data source: Gradstein et al. 2017
First occurrence (base): within Late Bajocian Substage (168.17-169.70Ma, base in Bajocian stage). Data source: Gradstein et al. 2017
Plot of range and occurrence data:
Gradstein, F. & Waskowska, A. (2021). New insights into the taxonomy and evolution of Jurassic planktonic foraminifera. Swiss Journal of Palaeontology. 140(1): 1-12. gs O Gradstein, F. M., Gale, A. S., Kopaevich, L., Waskowska, A., Grigelis, A. & Glinskikh, L. (2017b). The planktonic foraminifera of the Jurassic. Part I: material and taxonomy. Swiss Journal of Palaeontology. 136(2): 187-257. gs O Kendall, S., Gradstein, F., Jones, C., Lord, O. T. & Schmidt, D. N. (2020). Ontogenetic disparity in early planktic foraminifers. Journal of Micropalaeontology. 39: 27-39. gs O Morozova, V. G. & Moskalenko, T. A. (1961). Планктонные фораминиферы пограничных отложений байосского и батского ярусов Центрального Дагестана (Северо-Восточный Кавказ) [Foraminiferes planctoniques des depots limitrophes du Bajocien et du Bathonien du Daghestan central (Nord-Est du Caucase)]. Voprosyi Mikropaleontologii. 5: 3-30. gs Simmons, M. D., Boudagher-Fadel, M. K., Banner, F. T. & Whittaker, J. E. (1997). The Jurassic Favusellacea, the earliest Globigerina. In, Boudagher-Fadel, M. K., Banner, F. T. & Whittaker, J. E. (eds) The Early Evolutionary History of Planktonic Foraminifera. British Micropalaeontological Society Publication Series . 17-30. gs References:
Globuligerina balakhmatovae compiled by the pforams@mikrotax project team viewed: 8-9-2024
Short stable page link: https://mikrotax.org/pforams/index.php?id=110057 Go to Archive.is to create a permanent copy of this page - citation notes |
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