Syracosphaera gaarderae HOL

Classification: ntax_cenozoic -> Holococcoliths -> flat-topped -> Poricalyptra -> Syracosphaera gaarderae HOL
Sister taxa: P. aurisinae, P. isselii, P. magnaghii, S. gaarderae HOL, P. sp.


Citation: Syracosphaera gaarderae (Borsetti & Cati 1976) Keuter, Young & Frada 2019 HOL
Rank: Species
Basionym: Helladosphaera gaarderii Borsetti & Cati 1976
Taxonomic discussion: Keuter et al. (2019) discovered combination coccospheres proving that the species then known as Alveosphaera bimurata (Okada & McInytre 1977) and Poricalyptra gaarderae (Borsetti & Cati 1976) were life-cycle phases of a single species. They also confirmed records of exothcal cocoliths (Jordan et al. 2004) which proved the species should be recombined in Syracosphaera. Hence they proposed the new combination Syracosphaera gaarderae.

Distinguishing features: 2 irregular pores in distal surface.
1 concentric ring of crystallites around margin

Farinacci & Howe catalog pages: H. gaarderii *

Biology & life-cycles: The association of this holococcolith with the heterococcolith phase is based on observation of four separate combination coccospheres, including two unambiguous, well-formed ones.

See also: Syracosphaera gaarderae - heterococcolith stage (formerly Alveosphaera bimurata);

Search data:
TagsLITHS: holococcolith, elliptical, hollow, CA: pores,
CSPH: elongated, CFC, CROSS-POLARS: V-prominent, R-prominent,
MetricsLith size: 1.7->2.4µm; Coccosphere size: 7->12µm; Liths per sphere: 50->100
Data source notes: csph size from illustrated specimens;
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:


Borsetti, A. M. & Cati, F. (1976). Il Nannoplancton calcareo vivente nel Tirreno Centro-meridionale. Parte II. Giornale di Geologia. 40(1): 209-240. gs V O

Jordan, R. W., Cros, L. & Young, J. R. (2004). A revised classification scheme for living Haptophytes. Micropaleontology. 50(supplement 1): 55-79. gs

Keuter, S., Young, J. R. & Frada, M. J. (2019). Life cycle association of the coccolithophore Syracosphaera gaarderae comb. nov. (ex Alveosphaera bimurata): Taxonomy, ecology and evolutionary implications. Marine Micropaleontology. 148: 58-64. gs

Kleijne, A. (1991). Holococcolithophorids from the Indian Ocean, Red Sea, Mediterranean Sea and North Atlantic Ocean. Marine Micropaleontology. 17: 1-76. gs

Okada, H. & McIntyre, A. (1977). Modern coccolithophores of the Pacific and North Atlantic Oceans. Micropaleontology. 23(1): 1-55. 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, Special Issue. 1: 1-132. gs V O


Syracosphaera gaarderae HOL compiled by Jeremy R. Young, Paul R. Bown, Jacqueline A. Lees viewed: 12-4-2021

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