Classification: Mesozoic -> Watznaueriales -> Watznaueriaceae -> Cyclagelosphaera
Sister taxa: Bussonius, Cyclagelosphaera, Diazomatolithus, Lotharingius, Watznaueria, Ansulasphaera, Bibreviconus, Perchnielsenella,

Distinguishing features: Circular watznaueriacean coccoliths.

Daughter taxa: (blue => in age window 0-800Ma)
long ranging
Small to medium sized Cyclagelosphaera with closed central area.
mid-late Cretaceous
Cyclagelosphaera with central-plug-forming inner tube cycle that forms a raised conical structure.
Cyclagelosphaera with central-plug-forming inner tube cycle that forms a raised conical structure.
Circular, with relatively wide central area filled with radial elements forming a coarse grill or plate.
Cyclagelosphaera with narrow distal shield and broad, elevated, mid-tube cycle.
Jurassic/Early Cretaceous
A large, concavo-convex species of Cyclagelosphaera (6-11 µm) having a broad, distal shield inner cycle and a small central perforation.
Medium to large Cyclagelosphaera with closed central area, small proximal shield, large elements, and indistinct V-units cycle.
Medium to large (6-10 µm) with, closed, elliptical central area 
Large (>9µm) Cyclagelosphaera with a closed central area.
Medium-sized Cyclagelasphaera with an open central area, equivalent in width to that of the shield width. Grill of rotated bars in well-preserved specimens.
Small to medium sized Cyclagelosphaera with central opening.
Large sized (8-9 µm) with small central opening and inconspicuous tube cycle.
Specimens not identified to species level


Citation: Cyclagelosphaera Noël, 1965
Rank: Genus
Type species: Cyclagelosphaera margerelii Noël, 1965.
Notes & discussion: Arguably a junior synonym of Tergestiella Kamptner 1941

Farinacci & Howe catalog pages: Cyclagelosphaera *

Distinguishing features: Circular watznaueriacean coccoliths.

Search data:
TagsLITHS: placolith, circular, CA: ca_conjunct, closed,
CSPH: equant, monomorphic, CROSS-POLARS: rim-unicyclic, R-prominent,
MetricsLith size: 5->14µm;
Data source notes: size range of included species
The morphological data given here can be used on the advanced search page. See also these notes

Geological Range:
Notes: Last appearance was thought be in the early Eocene (e.g. Bybell & Self-Trail, 1995) but it has recently been shown to be extant by Hagino et al. (2015).  Some authors have claimed an earlier origination.
Last occurrence (top): in lower part of Ypresian Stage (22% up, 54.2Ma, in Ypresian stage). Data source: Total of range of species in this database
First occurrence (base): in upper part of Bajocian Stage (81% up, 168.7Ma, in Bajocian stage). Data source: Total of range of species in this database

Plot of occurrence data:


Bown, P. R. & Cooper, M. K. E. (1998). Jurassic. In, Bown, P. R. (ed.) Calcareous Nannofossil Biostratigraphy. British Micropalaeontological Society Publication Series. 34-85. gs

Bybell, L. M. & Self-Trail, J. (1995). Evolutionary, biostratigraphic and taxonomic study of calcareous nanofossils from a continuous Palaeocene-Eocene boundary section in New Jersey. U.S. Geological Survey, Professional Paper. 1554: 1-36. gs V O

Hagino, K. et al. (2015). Re-discovery of a “living fossil” coccolithophore from the coastal waters of Japan and Croatia. Marine Micropaleontology. 116(1): 28-37. gs

Kamptner, E. (1941). Die Coccolithineen der Südwestküste von Istrien. Annalen des Naturhistorischen Museums in Wien. 51: 54-149. gs V O

Noël, D. (1965b). Sur les Coccolithes du Jurassique Européen et d'Afrique du Nord. Éditions du Centre National de la Recherche Scientifique, Paris. 1-209. gs


Cyclagelosphaera compiled by Jeremy R. Young, Paul R. Bown, Jacqueline A. Lees viewed: 29-9-2020

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