Pontosphaera exilis


Classification: ntax_cenozoic -> Zygodiscales -> Pontosphaeraceae -> Pontosphaera -> Pontosphaera exilis
Sister taxa: << < P. hollisii, P. romansii ⟩⟨ P. japonica, P. plana, P. rimosa ⟩⟨ P. pectinata, P. wilsonii, P. punctosa, P. clinosulcata, P. perforomarginata, P. pulcheroides, P. pulchra, P. pygmaea ⟩⟨ P. ocellata, P. duocava, P. exilis, P. pax ⟩⟨ P. obliquipons, T. omarians ⟩⟨ P. sp.

Taxonomy:

Citation: Pontosphaera exilis (Bramlette & Sullivan, 1961) Romein, 1979
Rank: Species
Basionym: Discolithus exilis Bramlette & Sullivan, 1961
Synonyms: Discolithina rectipons Haq (1968) = Transversopontis rectipons (Haq 1968) Roth 1970

Distinguishing features: Simple unadorned plate with two large holes that define a transverse bar; the rim is narrow and not distinct in XPL. Hole size, and thus bar width, varies greatly. The bar is typically transverse but may be slightly oblique.

Farinacci & Howe catalog pages: D. exilis * , D. rectipons *

Search data:
TagsLITHS: murolith, elliptical, CA: ca_conjunct, pores, bar, CROSS-POLARS: rim-bicyclic, V-prominent, R-prominent,
MetricsLith size: 5->12µm;
Data source notes: lith size from illustrated specimens (OD suggests can be larger)
The morphological data given here can be used on the advanced search page. See also these notes

Geological Range:
Last occurrence (top): within NP17 zone (37.32-40.40Ma, top in Priabonian stage). Data source: Bown 2005
First occurrence (base): within NP9 zone (55.86-57.21Ma, base in Thanetian stage). Data source: Bown 2005

Plot of occurrence data:

References:

Bown, P. R. & Newsam, C. (2017). Calcareous nannofossils from the Eocene North Atlantic Ocean (IODP Expedition 342 Sites U1403–1411). Journal of Nannoplankton Research. 37(1): 25-60. gs V O

Bown, P. R. (2005d). Palaeogene calcareous nannofossils from the Kilwa and Lindi areas of coastal Tanzania (Tanzania Drilling Project 2003-4). Journal of Nannoplankton Research. 27(1): 21-95. gs V O

Bown, P. R. (2010). Calcareous nannofossils from the Paleocene/Eocene Thermal Maximum interval of southern Tanzania (TDP Site 14). Journal of Nannoplankton Research. 31(1): 11-38. gs V O

Bramlette, M. N. & Sullivan, F. R. (1961). Coccolithophorids and related nannoplankton of the Early Tertiary in California. Micropaleontology. 7(2): 129-188. gs

Bybell, L. (1975). Middle Eocene calcareous nannofossils at Little Stave Creek, Alabama. Tulane Studies in Geology and Paleontology. 11(4): 177-247. gs V O

Jones, A. P. & Dunkley Jones, T. (2020). Middle Eocene to Early Oligocene calcareous nannofossils from the Nanggulan Formation, Java, Indonesia. Journal of Nannoplankton Research. 30(1): 57-79. gs V O

Romein, A. J. T. (1979). Lineages in Early Paleogene calcareous nannoplankton. Utrecht Micropaleontological Bulletin. 22: 1-231. gs V O

Shepherd, C. L. & Kulhanek, D. K. (2016). Eocene nannofossil biostratigraphy of the mid-Waipara River section, Canterbury Basin, New Zealand. Journal of Nannoplankton Research. 26(1): 33-59. gs V O


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Pontosphaera exilis compiled by Jeremy R. Young, Paul R. Bown, Jacqueline A. Lees viewed: 20-4-2021

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Short stable page link: https://mikrotax.org/Nannotax3/index.php?id=1072 Go to Archive.is to create a permanent copy of this page - citation notes



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