Nannotax3 - ntax_cenozoic - Quadrilateris imparidividuus Nannotax3 - ntax_cenozoic - Quadrilateris imparidividuus

Quadrilateris imparidividuus

Classification: ntax_cenozoic -> Holococcoliths -> fossil holococcoliths -> Quadrilateris -> Quadrilateris imparidividuus
Sister taxa: Q. imparidividuus, Q. sp.


Citation: Quadrilateris imparidividuus Varol, 1991
taxonomic rank: Species
Taxonomic discussion: Similar to Youngilithus oblongatus in overall shape but exhibits high birefringence and lacks lateral rim projections.

Distinguishing features:
Parent taxon (Quadrilateris): Rectangular holococcoliths formed from four thin blocks that are birefringent in XPL.
This taxon: A small, narrowly rectangular holococcolith formed from four thin blocks that are birefringent in XPL.

Farinacci & Howe catalog pages: Q. imparidividuus *

Search data:
LITHS: holococcolith, quadrate, CA: bar, CROSS-POLARS: R-prominent,
Lith size: 2->4µm; Segments: 4->4;
Data source notes: lith size from illustrated specs (OD gives size as 5.0µm bu tfigure suggests nearer 4 µm)
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 2005
First occurrence (base): within NP15 zone (42.87-46.29Ma, base in Lutetian stage). Data source: Varol, 1991

Plot of occurrence data:


Bown, P. R. & Dunkley Jones, T. (2006). New Paleogene calcareous nannofossil taxa from coastal Tanzania: Tanzania Drilling Project Sites 11 to 14. Journal of Nannoplankton Research. 28(1): 17-34. gs

Dunkley Jones, T., Bown, P. R. & Pearson, P. (2009). Exceptionally well preserved upper Eocene to lower Oligocene calcareous nannofossils (Prymnesiophycidae) from the Pande Formation (Kilwa Group), Tanzania. Journal of Systematic Palaeontology. 7(4): 359-411. gs

Varol, O. (1991). New Cretaceous and Tertiary Calcareous Nannofossils. Neues Jahrbuch für Geologie und Paläontologie, Abhandlungen. 182: 211-237. gs


Quadrilateris imparidividuus compiled by Jeremy R. Young, Paul R. Bown, Jacqueline A. Lees viewed: 21-4-2024

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