Nannotax3 - ntax_cenozoic - Rhomboaster cuspis Nannotax3 - ntax_cenozoic - Rhomboaster cuspis

Rhomboaster cuspis

Classification: ntax_cenozoic -> Nannolith families inc sed -> Rhomboasteraceae -> Rhomboaster -> Rhomboaster cuspis
Sister taxa: R. bramlettei, R. calcitrapa, R. cuspis, R. sp.


Citation: Rhomboaster cuspis Bramlette & Sullivan, 1961
Rank: Species
Variants: Marthasterites riedeli Brönnimann & Stradner (1960) - similar but with pores in the rays
Taxonomic discussion: Regarded as a variant of R. bramlettei by Bybell & Self-Trail (1995)

Distinguishing features:
Parent taxon (Rhomboaster): Solid nannoliths that include rhombic, rhombic with spinose extensions and forms composed of two superimposed tri-radiate cycles.
This taxon: Rhombic Rhomboaster nannoliths with little or no extensions from the points of the rhomb.

Farinacci & Howe catalog pages: R. cuspis * , M. riedeli *

Search data:
LITHS: nannolith-radiate, quadrate, star-shaped, CROSS-POLARS: 1ou, V-prominent,
Lith size: 5->10µm; Segments: 8->8;
Data source notes: lith size from OD & illustrated specimens
The morphological data given here can be used on the advanced search page. See also these notes

Geological Range:
Notes: Almost confined to the PETM.
Last occurrence (top): near base of NP10 zone (5% up, 55.8Ma, in Ypresian stage). Data source: Agnini et al. 2007 fig 8, 9
First occurrence (base): at top of NP9 zone (95% up, 55.9Ma, in Ypresian stage). Data source: Agnini et al. 2007 fig 8, 9

Plot of occurrence data:


Agnini, C., Fornaciari, E., Raffi, I., Rio, D., Rohl, U. & Westerhold, T. (2007a). High-resolution nannofossil biochronology of middle Paleocene to early Eocene at ODP Site 1262: Implications for calcareous nannoplankton evolution. Marine Micropaleontology. 64: 215-248. gs

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 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 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. M. & Self-Trail, J. (1995). Evolutionary, biostratigraphic and taxonomic study of calcareous nanofossils from a continuous Palaeocene-Eocene boundary section in New Jersey. U.S. Geological Survey, Professional Paper. 1554: 1-36. gs O

Müller, C. (1979). Calcareous nannofssils from the North Atlantic (Leg 48). Initial Reports of the Deep Sea Drilling Project. 48: 589-639. gs

Shepherd, C. L. & Kulhanek, D. K. (2016). Eocene nannofossil biostratigraphy of the mid-Waipara River section, Canterbury Basin, New Zealand. Journal of Nannoplankton Research. 36(1): 33-59. gs O


Rhomboaster cuspis compiled by Jeremy R. Young, Paul R. Bown, Jacqueline A. Lees viewed: 2-12-2023

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