Nannotax3 - ntax_cenozoic - Holococcoliths Nannotax3 - ntax_cenozoic - Holococcoliths

Holococcoliths


Classification: ntax_cenozoic -> Holococcoliths
Sister taxa: Isochrysidales, Coccolithales, Zygodiscales, Syracosphaerales, Coccolith families inc sed, Mesozoic Survivors ⟩⟨ Holococcoliths, Braarudosphaerales, Discoasterales, Nannolith families inc sed, hidden

Daughter taxa (time control age-window is: 0-800Ma)Granddaughter taxa
tubeless
Holococcoliths without a tube, flat or cap-shaped
Sphaerocalyptra
Syracosphaera HOL (Anthosphaera type)
fried egg monomorphic
flat dimorphic
flat (coccolithaceae HOLs)
flat trapezoidal
tubeless-minute

convex
Holococcoliths with tube, covered distally by a convex cover
Calyptrosphaera sphaeroidea HOL
Syracosphaera pulchra HOL oblonga type
Syracosphaera pulchra HOL pirus type
Syracosphaera pulchra HOL galea type
Calyptrolithina divergens
Calyptrosphaera heimdaliae
Calyptrosphaera lluisae
Calyptrosphaera radiata
Flosculosphaera
Gliscolithus

bridged
Holococcoliths with tube, spanned distally by a bridge
Corisphaera
Helladosphaera
Homozygosphaera
Poritectolithus
Syracosphaera anthos HOL

flat-topped
Holococcoliths with tube, covered distally by a flat cover
Helicosphaera HOL
Holococcolithophora -flat
S. aurisinae HOL type
S. mediterranea HOL type
Zygosphaera

septate
Holococcoliths with tube, open distally and subdivided internally by vertical septae
Calcidiscus leptoporus subsp. quadriperforatus HOL
Scyphosphaera apsteinii HOL
Pontosphaera japonica HOL
Syracolithus sp. type A
Syracolithus sp. type B
Syracolithus bicorium

open-tube
Holococcoliths with tube, open distally (or cover recessed)
Calicasphaera
Papposphaera HOL
Trigonaspis

fossil holococcoliths
Holococcolith genera only known from the fossil record

Unidentified extant holococcolith


Taxonomy:

Citation: Holococcoliths sensu Young et al., 2003
taxonomic rank: informal group of families
Synonyms: Family Calyptrosphaeraceae Boudreaux & Hay, 1969.
Taxonomic discussion: It used to be conventional to place all holococcoliths in the Famly Calyptrosphaeraceae, however this is manifestly artificial, since it is now known that holococcoliths are formed during the haploid life-cycle stage of species belonging to numerous different families. Moreover, the type species of the Family Calyptrosphaeraceae, Calyptrosphaera oblonga, is now known to be a life-cycle phase of Syracosphaera pulchra, hence the name Calyptrosphaeraceae is a junior synonym of Syracosphaeraceae.
It is still convenient to group the holococcoliths together for identification purposes, but giving this artificial grouping a formal taxonomic name (e.g. Calyptrosphaeraceae) is no longer defensible.
Similarly the generic classification is increasingly anachronistic as more life cycle comobinations are discovered. We do still use traditional names but the groupings used here are based on morphology.

Distinguishing features:
Parent taxon (ntax_cenozoic): Extant coccolithophores and Cenozoic calcareous nannofossils - Mesozoic nannofossils are in a separate module
This taxon: Haploid life-cycle stages, with liths formed of numerous rhombohedral microcrystals

Farinacci & Howe catalog pages: Holococcoliths [no catalog entry yet], Calyptrosphaeraceae


Morphology:

Holococcoliths are formed of numerous, minute rhombohedral calcite crystallites (Young & Henriksen 2003). They are produced during the haploid phase of the life-cycle of a wide range of coccolithophores that bear heterococcoliths in their diploid life-cycle phase.

Search data:
Lith size: 0->0µm;
The morphological data given here can be used on the advanced search page. See also these notes

Geological Range:
Notes: Although diverse holococcolith assemblages have been described from Cretaceous and Palaeogene assemblages, they are virtually absent from Neogene nannofloras. This is rather surprising, given that modern nannofloras include >60 holococcolithophores (see, e.g., Kleijne, 1991; Jordan & Kleijne, 1994; Young et al. 2003), but most species produce very small holococcoliths (often <2µm) with low preservation potential.
Last occurrence (top): Extant. Data source: Total of ranges of the species in this database
First occurrence (base): within Campanian Stage (72.17-83.65Ma, base in Campanian stage). Data source: Total of ranges of species in this database

Plot of occurrence data:

References:

Boudreaux, J. E. & Hay, W. W. (1969). Calcareous nannoplankton and biostratigraphy of the late Pliocene-Pleistocene-Recent sediments in the Submarex cores. Revista Española de Micropaleontología. 1(3): 249-292. gs O

Jordan, R. W. & Kleijne, A. (1994). A classification system for living coccolithophores. In, Winter, A. & Siesser, W. G. (eds) Coccolithophores. Cambridge University Press, Cambridge 83-105. gs

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

Young, J. R. & Henriksen, K. (2003). Biomineralization within vesicles: the calcite of coccoliths. Reviews in Mineralogy and Geochemistry. 54(1): 189-215. 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


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Holococcoliths compiled by Jeremy R. Young, Paul R. Bown, Jacqueline A. Lees viewed: 12-11-2024

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Short stable page link: https://mikrotax.org/Nannotax3/index.php?id=714 Go to Archive.is to create a permanent copy of this page - citation notes
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