Nannotax3 - ntax_cenozoic - Braarudosphaera

Citation: Braarudosphaera Deflandre, 1947

Type species: Pontosphaera bigelowii Gran & Braarud 1935.

Synonyms: 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.

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

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 Albian stage). Data source: Total of range of species in this database

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 V O

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 V O

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

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

Braarudosphaera

References:

Comments (0)

Add Comment