Classification: ntax_cenozoic -> Holococcoliths -> tubeless
Sister taxa: tubeless, convex, bridged, flat-topped, septate, open-tube, fossil holococcoliths, U. extant holococcolith

Daughter taxa (time control age-window is: 0-800Ma)Granddaughter taxa
dimorphic BCs conical, may have large openings, CFCs higher

fried egg shape, dimorphic (CFCs with large leaf-like process)

fried egg monomorphic
BCs with flat rim and central protrusion, no marginal perforations, CFCs similar to BCs

flat dimorphic
BCs disks, may have ridge
CFCs with transverse ridge of bridge

flat (coccolithaceae HOLs)
Liths are planar disks, variable ultrastructure. Cocospheres monomorphic. The species were formerly in Crystallolithus

flat trapezoidal
liths similar to and associated with Florisphaera

Lightly calcified holococcoliths, <1µm across; typically organic scales with weak calcification


Citation: Holococcoliths without tube - informal grouping proposed by Young et al., 2003
Rank: informal group of genera

Distinguishing features: Holococcoliths without a tube, flat or cap-shaped

Farinacci & Howe catalog pages: tubeless [no catalog entry yet]

Search data:
MetricsLith size: 0->0µm;
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: Total of range of species in this database
First occurrence (base): at base of Gelasian Stage (0% up, 2.6Ma, in Gelasian stage). Data source: Total of range of species in this database

Plot of occurrence data:


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


tubeless compiled by Jeremy R. Young, Paul R. Bown, Jacqueline A. Lees viewed: 13-6-2021

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Short stable page link: Go to to create a permanent copy of this page - citation notes

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