Nannotax3 - ntax_cenozoic - Cyrtosphaera cidaris Nannotax3 - ntax_cenozoic - Cyrtosphaera cidaris

Cyrtosphaera cidaris

Classification: ntax_cenozoic -> Syracosphaerales -> Rhabdosphaeraceae -> Cyrtosphaera -> Cyrtosphaera cidaris
Sister taxa: C. aculeata, C. cidaris, C. sp.


Citation: Cyrtosphaera cidaris (Schlauder 1945) Young & Bown 2014
taxonomic rank: Species
Basionym: Acanthoica cidaris Schlauder 1945
Synonyms: Anacanthoica cidaris (Schlauder 1945) Kleijne 1992
Variants: Differs from Cyrtosphaera aculeata in being monomorphic and protrusions do not end terminal papillae.
Taxonomic discussion: Young & Bown (2014) transferred this species from Anacanthoica to Cyrtosphaera since it is varimorphic but lacks long pole coccoliths

Distinguishing features:
Parent taxon (Cyrtosphaera): Body coccoliths with well-developed radial lath cycle, protrusion in centre; coccospheres varimorphic higher protrusions on circum-flagellar coccoliths
This taxon: Coccoliths with narrow rim, broadly elliptical with slight inflection on sides;  sharp conical “witches hat” protrusion.

Farinacci & Howe catalog pages: C. cidaris [no catalog entry yet], A. cidaris undulata * , A. cidaris *


Although rare this is a distinctive species, and an excellent specimen was illustrated by Yang et al. 2012
Numrous (44-60 laths) in central area - this is another feature which distinguishes the species.

Search data:
LITHS: planolith, elliptical, CA: ca_disjunct, grill, process,
CSPH: equant, monomorphic,
Lith size: 2->3µm;
Data source notes: lith length from Kleijne 1992 & slightly extended
The morphological data given here can be used on the advanced search page. See also these notes

Geological Range:
Last occurrence (top): Extant. Data source: present in the plankton (Young et al. 2003)
First occurrence (base): within No known fossil record modern (0.00-0.00Ma, base in "Holocene" stage). Data source: [JRY rough estimate]

Plot of occurrence data:


Kleijne, A. (1992). Extant Rhabdosphaeraceae (coccolithophorids, class Prymnesiophyceae) from the Indian Ocean, Red Sea, Mediterranean Sea and North Atlantic Ocean. Scripta Geologica. 100: 1-63. gs

Konno, S. & Jordan, R. W. (2006). Lagoon coccolithophorids from the Republic of Palau, NW Equatorial Pacific. Journal of Nannoplankton Research. 28(2): 95-110. gs O

Schlauder, J. (1945). Recherches sur les flagellés calcaires de la Baie d'Alger. PhD thesis, Université d'Alger. 1-51. gs

Yang, T. -N., Wei, K. & Wu, J. -T. (2012). Marine coccolithophores around Taiwan. Biodiversity Research Center, Academica Sinica, Taipei. 1-96. gs

Young, J. R. & Bown, P. R. (2014). Some emendments to calcareous nannoplankton taxonomy. Journal of Nannoplankton Research. 33(1): 39-46. gs

Young, J. R., Geisen, M., Cros, L., Kleijne, A., Probert, I. & Ostergaard, J. B. (2003). A guide to extant coccolithophore taxonomy. Journal of Nannoplankton Research. S1: 1-132. gs


Cyrtosphaera cidaris compiled by Jeremy R. Young, Paul R. Bown, Jacqueline A. Lees viewed: 14-4-2024

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