Coronocyclus baileyi

Classification: ntax_cenozoic -> Coccolithales -> Coccolithaceae -> Coronocyclus -> Coronocyclus baileyi
Sister taxa: C. nitescens, C. mesostenos, C. baileyi, C. lordii, C. sp.


Citation: Coronocyclus baileyi da Gama & Varol 2013
Rank: Species
Taxonomic discussion: Boesiger et al. (2017) noted that the type specimens of C. baileyi have unusually narrow rims, and are described from outside the normal range for elliptical Coronocyclus. They proposed C. mesostenos as an alternate name for the more typical specimens.

Distinguishing features: Elliptical Coronocyclus species, with narrow rim

Original description: Diagnosis: Elliptical species of Coronocyclus.

Description: This elliptical form has a proximal and distal shield of equal size and a large central opening. The dextrally imbricated lath-like elements of the distal shield have short spine-like projections in well-preserved specimens (more distinct under SEM, see Pl4, Fig.3-4). The proximal shield and tube cycle are also made up of dextrally imbricated wedge-shaped elements. In some specimens, spine-like distal projections are also present on the elements of the tube cycle but it is difficult to determine whether they are primary features or the result of digenetic alteration. Under polarised light the shields and tube cycle appear strongly serrated.

Farinacci & Howe catalog pages: C. baileyi *

Search data:
TagsLITHS: placolith, elliptical, CA: vacant,
CSPH: equant, monomorphic, CROSS-POLARS: rim-bicyclic, V-prominent, R-prominent,
MetricsLith size: 4->8µm;
The morphological data given here can be used on the advanced search page. See also these notes

Geological Range:
Notes: da Gama & Varol 2013 record specimens from higher in the Miocene (NN8-10) but confusion with C. pelagicus proto-coccolith rings is possibly the cause of these records.
Last occurrence (top): within NN9 zone (9.53-10.55Ma, top in Tortonian stage). Data source: da Gama & Varol 2013
First occurrence (base): within NN4 zone (14.91-17.95Ma, base in Burdigalian stage). Data source: da Gama & Varol 2013

Plot of occurrence data:


Boesiger, T. M., de Kaenel, E., Bergen, J. A., Browning, E. & Blair, S. A. , . (2017). Oligocene to Pleistocene taxonomy and stratigraphy of the genus Helicosphaera and other placolith taxa in the circum North Atlantic Basin. Journal of Nannoplankton Research. 37(2-3): 145-175. gs V O

da Gama, R. O. B. P. & Varol, O. (2013). New Late Oligocene to Miocene Species. Journal of Nannoplankton Research. 33(1): 1-12. gs V O

Young, J. R. (1998). Neogene. In, Bown, P. R. (ed.) Calcareous Nannofossil Biostratigraphy. British Micropalaeontological Society Publication Series. 225-265. gs V O


Coronocyclus baileyi compiled by Jeremy R. Young, Paul R. Bown, Jacqueline A. Lees viewed: 28-2-2021

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