Radiolithus undosus

Classification: Mesozoic -> Braarudosphaerales -> Polycyclolithaceae -> Radiolithus -> Radiolithus undosus
Sister taxa: R. laingii, R. hollandicus, R. orbiculatus, R. planus, R. undosus, R. sp.,

Distinguishing features: Radiolithus 9 wall-elements, low wall and outline star-like


Citation: Radiolithus undosus (Black, 1973) Varol, 1992
Rank: Species
Basionym: Rhombogyrus undosus Black, 1973
Notes & discussion: The holotype is a low walled eprolithid with nine petaloid wall-elements, and so is very similar to, or the same as, the Radiolithus planus species concept. Varol (1992) further considered that one cycle is stellate the other not.

Farinacci & Howe catalog pages: Rhombogyrus undosus *

Distinguishing features: Radiolithus 9 wall-elements, low wall and outline star-like

Search data:
TagsLITHS: nannolith-radiate, circular, star-shaped, cylindrical, CA: vacant, closed, T-UNITS: T-prominent,
MetricsLith size: 5->8µm; Segments: 9->9;
Sources: original description & illustrated specimens
The morphological data given here can be used on the advanced search page. See also these notes

Geological Range:
Last occurrence (top): within Late Cenomanian Substage (93.90-95.47Ma, top in Cenomanian stage). Data source: PRB nannotax entry
First occurrence (base): within Middle Albian Substage (107.59-110.22Ma, base in Albian stage). Data source: PRB nannotax entry

Plot of occurrence data:

  • Histogram - Neptune occurrence data from DSDP and ODP proceedings. Pale shading <50 samples in time bin. Interpret with caution & read these notes
  • Note to users in China - the diagram may not plot unless you use a VPN since I use google services on the website. If this is a problem please contact me 谢谢.
  • Taxon plotted: Radiolithus undosus, synonyms included - Radiolithus undosus;
  • space-time plot :: Samples map :: Parent: Radiolithus


    Black, M. (1973). British Lower Cretaceous Coccoliths. I-Gault Clay (Part 2). Palaeontographical Society Monograph. 127: 49-112. gs :: ::

    Bralower, T. J. & Bergen, J. A. (1998). Cenomanian-Santonian calcareous nannofossil biostratigraphy of a transect of cores drilled across the Western Interior Seaway. In, Dean, W. E. & Arthur, M. A. (eds) Stratigraphy and paleoenvironments of the Cretaceous Western Interior Seaway. SEPM Concepts in Sedimentology and Paleontology. -. gs :: ::

    Varol, O. (1992). Taxonomic revision of the Polycyclolithaceae and its contribution to Cretaceous biostratigraphy. Newsletters on Stratigraphy. 27(93-127): -. gs :: ::


    Radiolithus undosus compiled by Jeremy R. Young, Paul R. Bown, Jacqueline A. Lees viewed: 6-7-2020

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