Nannotax3 - ntax_main - Braarudosphaera

Nannotax3 - ntax_main - Braarudosphaera Nannotax3 - ntax_main - Braarudosphaera

Braarudosphaera

Classification: ntax_main -> Braarudosphaerales -> Braarudosphaeraceae -> Braarudosphaera
Sister taxa: Braarudosphaera, Micrantholithus ⟩⟨ Hexadelus, Pemma, Pentaster ⟩⟨ Bukryaster, Trapezopentus

Daughter taxa (time control age-window is: 0-800Ma)		Granddaughter taxa
	Extant species (see notes on B. bigelowii page)
	Braarudosphaera parkeae Pentaliths large to very large (11-13 µm across) Motile cells 15-35 µm long 18S genotypes IV, V	Braarudosphaera parkeae S-cells
	Braarudosphaera bigelowii Pentaliths large (8-10.5 µm across) Motile cells 10-20 µm long 18S genotype III	Braarudosphaera bigelowii S-cells Braarudosphaera bigelowii - Cenozoic Braarudosphaera bigelowii - Cretaceous
	Braarudosphaera okadae Pentaliths medium sized (6-7.5 µm across) Motile cells 4-10 µm long 18S genotypes I, II	Braarudosphaera okadae S-cells
	Braarudosphaera small form Pentaliths small (2.2-3.8 µm across) (Motile cells not yet identified)
	Braarudosphaera magnei Pentaliths rounded, and overlapping irregularly on coccosphere
	Fossil species
	Braarudosphaera - Cenozoic	Braarudosphaera alta Braarudosphaera insecta Braarudosphaera pentagonica Braarudosphaera perampla Braarudosphaera perversus Braarudosphaera sequela Braarudosphaera stylifera Braarudosphaera sp.
	Braarudosphaera - Cretaceous	Braarudosphaera africana Braarudosphaera amputans Braarudosphaera batilliformis Braarudosphaera pseudobatilliformis Braarudosphaera turbinea Braarudosphaera wendlerae Braarudosphaera sp. Cretaceous

Taxonomy:

Citation: Braarudosphaera Deflandre 1947

Taxonomic rank: genus

Type species: Pontosphaera bigelowii Gran & Braarud 1935.

Taxonomic discussion:

The vast majority of Braarudosphaera specimens are flat and have straight edges, traditionally these have all been placed in B. bigelowii. The work of Hagino et al (2009, 2026) has shown this is an oversimplification and at least 4 gentoypically distinct species occur with discrete size ranges (see B. bigelowii page for details). These species are outlined here for the extant population, but detailed work on size variation in the fossil record is needed before this can be extended beyond the Quaternary. [my interpretation - JRY 2026]

Synonyms:

Braarudosphaera * Deflandre 1947
Eodiscoaster * Martini 1961 [based on an overgrown specimen of Braarudosphaera according to Martini (1971) and Perch-Nielsen (1985)]

Variants:

Quinquerhabdus * Bukry & Bramlette 1969 [genus for strongly elevated and abruptly tapering specimens. In practice most authors would include these in Braarudosphaera.]

Distinguishing features:
Parent taxon (Braarudosphaeraceae): Coccospheres pentagonal dodecahedra formed of five pentagonal plates
This taxon: Pentaliths approximately pentagonal, sutures go to edges of pentagon.

Morphology:

Pentaliths approximately pentagonal, sutures go to edges of pentagon. NB In Micrantholithus sutures go to vertices of the pentagon.

Search data:

Lith size: 2->21µm; Segments: 5->5; Coccosphere size: 4->42µm; Liths per sphere: 12->12

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 ranges of the species in this database
First occurrence (base): within Aptian Stage (113.20-121.40Ma, base in Aptian stage). Data source: Total of ranges of species in this database

Plot of occurrence data:

Range-bar - range as quoted above, pink interval top occurs in, green interval base occurs in.
Triangles indicate an event for which a precise placement has been suggested.
See also:

Parent: Braarudosphaeraceae

References:

Bown, P. R., Rutledge, D. C., Crux, J. A. & Gallagher, L. T. (1998). Lower Cretaceous. In, Bown, P. R. (ed.) Calcareous Nannofossil Biostratigraphy. British Micropalaeontological Society Publication Series . 86-131. gs O

Bukry, D. & Bramlette, M. N. (1969b). Some new and stratigraphically useful calcareous nannofossils of the Cenozoic. Tulane Studies in Geology. 7: 131-142. gs

Deflandre, G. (1947a). Braarudosphaera nov. gen., type d'une famille nouvelle de Coccolithophorides actuels a elements composites. Comptes rendus hebdomaire de l'Académie des sciences, Paris. 225: 439-441. gs

Martini, E. (1961). Nannoplankton aus dem Tertiär und der obersten Kreide von SW-Frankreich. Senckenbergiana Lethaea. 42: 1-32. gs

Martini, E. (1971a). Die Typen und Typoide des Natur-Museums Senckenberg, 46): Fossiles Nannoplankton. Senckenbergiana Lethaea. 52: 115-127. gs

Perch-Nielsen, K. (1985). Cenozoic calcareous nannofossils. In, Bolli, H. M., Saunders, J. B. & Perch-Nielsen, K. (eds) Plankton Stratigraphy. Cambridge University Press, Cambridge (1): 427-555. gs

Braarudosphaera compiled by Jeremy R. Young, Paul R. Bown, Jacqueline A. Lees viewed: 7-10-2026

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Short stable page link: https://mikrotax.org/Nannotax3/index.php?id=145 Go to Archive.is to create a permanent copy of this page - citation notes

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