R. reticulata group


Classification: ntax_cenozoic -> Isochrysidales -> Noelaerhabdaceae -> Reticulofenestra -> R. reticulata group
Sister taxa: C. floridanus group, R. bisecta group, R. lockeri group, R. parvula group, R. pseudoumbilicus group, R. reticulata group, R. umbilicus group, R. sp.

Daughter taxa (time control age-window is: 0-800Ma)
Reticulofenestra reticulata
Medium to large (~8-12µm), circular reticulofenestrids with narrow central area crossed by a distinctive, robust, visible grill.
Reticulofenestra isabellae
Similar to R. reticulata but >12µm
Reticulofenestra erbae
Similar to R. reticulata but with broad tube and closed central area.
Reticulofenestra nanggulanensis
Like R. reticulata but smaller (5-8 µm) and with wide central area (ca 1.5x rim width)
Reticulofenestra westerholdii
Similar to R. reticulata but smaller and without visible net
Cyclicargolithus artuziae
Small (up to 4µm) species with wide central area and robust grill
Reticulofenestra sp. cf. reticulata
Morphotypes intergrading with R. reticulata but lacking the distinctive central area structure

Taxonomy:

Citation: R. reticulata group
Rank: species group
Taxonomic discussion: Broadly, but not completely, correlates with the general usage of the genus Cribrocentrum Perch-Nielsen, 1971. This group includes the only strictly circular Paleogene reticulofenestrids but some smaller forms may have imperceptible (or lost) nets and there is some evidence of transitional subcircularity.

Distinguishing features: Typically circular reticulofenestrids with relatively narrow circular central area with robust grill (clearly visible in lm).

Farinacci & Howe catalog pages:


Ecology & Biogeography: This group is considered to be indicative of relatively warm water conditions (Bukry, 1973; Aubry, 1992a, b; Newsam et al., 2017, Jones & Dunkley Jones 2020)

Search data:
TagsLITHS:
MetricsLith size: 5->16µm;
The morphological data given here can be used on the advanced search page. See also these notes

Geological Range:
Notes: As defined this group is essentially restricted to the middle-upper Eocene.
Last occurrence (top): near top of Priabonian Stage (86% up, 34.4Ma, in Priabonian stage). Data source: Total of range of species in this database
First occurrence (base): in lower part of Ypresian Stage (28% up, 53.7Ma, in Ypresian stage). Data source: Total of range of species in this database

Plot of occurrence data:

References:

Aubry, M. -P. (1992a). Late Paleogene calcareous nannoplankton evolution: a tale of climatic deterioration. In, Prothero, D. R. & Berggren, W. A. (eds) Eocene-Oligocene Climatic and Biotic Evolution. Princeton University Press, Princeton 272-309. gs

Aubry, M-P. (1992b). Paleogene calcareous nannofossils from the Kerguelen Plateau, Leg 120. Proceedings of the Ocean Drilling Program, Scientific Results. 120: 471-491. gs V O

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 V O

Bukry, D. (1973e). Low-latitude coccolith biostratigraphic zonation. Initial Reports of the Deep Sea Drilling Project. 15: 685-703. 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

Newsam, C., Bown, P. R., Wade, B. S. & Jones, H. L. (2017). Muted calcareous nannoplankton response at the Middle/Late Eocene Turnover event in the western North Atlantic Ocean. Newsletters on Stratigraphy. 50(3): 297-309. gs


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R. reticulata group compiled by Jeremy R. Young, Paul R. Bown, Jacqueline A. Lees viewed: 1-3-2021

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Short stable page link: https://mikrotax.org/Nannotax3/index.php?id=1150 Go to Archive.is to create a permanent copy of this page - citation notes



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