Nannotax3 - ntax_cenozoic - Reticulofenestra westerholdii Nannotax3 - ntax_cenozoic - Reticulofenestra westerholdii

Reticulofenestra westerholdii

Classification: ntax_cenozoic -> Isochrysidales -> Noelaerhabdaceae -> Reticulofenestra -> R. reticulata group -> Reticulofenestra westerholdii
Sister taxa: R. reticulata, R. isabellae, R. erbae, R. nanggulanensis, R. westerholdii, C. helianthus, R. sp. cf. reticulata


Citation: Reticulofenestra westerholdii Bown & Dunkley Jones, 2012
taxonomic rank: Species

Distinguishing features:
Parent taxon (R. reticulata group): Typically circular reticulofenestrids with relatively narrow circular central area with robust grill (clearly visible in lm).
This taxon: Similar to R. reticulata but smaller and without visible net

Farinacci & Howe catalog pages: R. westerholdii * , R. laevis *


Medium sized (5-8µm), circular reticulofenestrids with open central area (similar in width to, or slightly narrower than, the rim width) but no perceptible net.

Distinguished from R. reticulata by the smaller size, narrower tube, proportionally wider central area and absence of visible net. Distinguished from C. floridanus by the circular outline, wider central area and low tube cycle

Holotype length 6.9µm.

See also: Reticulofenestra wadeae - similar but larger & central area broader;

Search data:
LITHS: placolith, circular, CA: ca_conjunct, grill, vacant,
CSPH: equant, monomorphic, CROSS-POLARS: rim-unicyclic, R-prominent,
Lith size: 5->8µm;
The morphological data given here can be used on the advanced search page. See also these notes

Geological Range:
Last occurrence (top): within NP19-20 zone (34.44-36.97Ma, top in Priabonian stage). Data source: Bown & Dunkley Jones, 2012
First occurrence (base): within NP16 zone (40.40-42.87Ma, base in Lutetian stage). Data source: Bown & Dunkley Jones, 2012

Plot of occurrence data:


Bown, P. R. & Dunkley Jones, T. (2012). Calcareous nannofossils from the Paleogene equatorial Pacific (IODP Expedition 320 Sites U1331-1334). Journal of Nannoplankton Research. 32(2): 3-51. gs O

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 O

De Kaenel, E. & Mojon, P. -O. (2023). Calcareous nannofossil biostratigraphy of the Eocene/Oligocene boundary (Zones NP19–21) in the parautochthonous Subalpine UMM of the Swiss Molasse Basin (Canton Fribourg, Western Switzerland). Journal of Nannoplankton Research. 41(2): 64-96. gs O

Hay, W. W., Mohler, H. P., Roth, P. H., Schmidt, R. R. & Boudreaux, J. E. (1967). Calcareous nannoplankton zonation of the Cenozoic of the Gulf Coast and Caribbean-Antillean area, and transoceanic correlation. Transactions of the Gulf-Coast Association of Geological Societies. 17: 428-480. gs 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. 38(1): 57-79. gs


Reticulofenestra westerholdii compiled by Jeremy R. Young, Paul R. Bown, Jacqueline A. Lees viewed: 14-7-2024

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