Braarudosphaera


Classification: Coccolithophores -> Braarudosphaerales -> Braarudosphaeraceae -> Braarudosphaera
Sister taxa: Braarudosphaera, Hexadelus, Micrantholithus, Pemma, Pentaster,

Daughter taxa: (blue => in age window 0-800Ma)
Pentaliths pentagonal with sraight edges and flat top surface
pentaliths large & with crenulate edges
Pentaliths rounded, and overlapping irregularly on coccosphere
Braarudosphaera with 5-sided segments
Large (>12µm) pentaliths with slightly rounded corners and convex upper surfaces
Braarudosphaera with ridge along the longer edge of each segment, giving rotated stellate appearance.
Stellate Braarudosphaera with protruding pentalith segments.
Elevated pentaliths that taper sharply from the base.
Specimens which cannot be assigned to established species

Taxonomy:

Citation: Braarudosphaera Deflandre, 1947
Rank: Genus
Type species: Pontosphaera bigelowii Gran & Braarud 1935.
Variants: Quinquerhabdus Bukry & Bramlette 1969 - genus for strongly elevated and abruptly tapering specimens. In practice most authors would include these in Braarudosphaera.
Synonyms: Eodiscoaster Martini 1961 - based on an overgrown specimen of Braarudosphaera according to Martini (1971) and Perch-Nielsen (1985)

Distinguishing features: Pentaliths approximately pentagonal, sutures go to edges of pentagon.

Farinacci & Howe catalog pages: Braarudosphaera * , Quinquerhabdus * , Eodiscoaster *


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

Search data:
TagsLITHS: nannolith-radiate, pentagonal,
CSPH: spherical, monomorphic, T-UNITS: all,
MetricsLith size: 2->21µm; Segments: 5->5; Coccosphere size: 4->42µm; Liths per sphere: 12->12
Sources:
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 Cenomanian Stage (0% up, 100.5Ma, in Cenomanian stage). Data source: Total of range of species in this database

Plot of occurrence data:

References:

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

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


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Braarudosphaera compiled by Jeremy R. Young, Paul R. Bown, Jacqueline A. Lees viewed: 6-12-2019

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Short stable page link: http://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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