Boesiger et al (2017) used the name Cyclicargolithus bukryi Wise for this species however Varol (2025) argues thatthis is inapropridte since the type of C. bukryi is too large to fit within the species concept hence they proposed a new name, R. dennei.
Boesiger et al. (2017) record that the taxon it is a valuable marker in the Gulf of Mexico - with 5 abundance based events being used.
Distinguishing features:
Parent taxon (C. floridanus group): Subcircular to broadly-elliptical reticulofenestrids with a narrow central area (spanned by delicate proximal net, not visible in lm)
This taxon: Small (3-5µm), circular, with moderately wide central opening. NN5
| Lith size: 3->5µm; Data source notes: Varol 2025, Boesiger et al. 2017 |
Varol (2025) records the species as confined to NN5. However, Boesiger et al (2017) state that, in the Gulf of Mexico, it has its base within NN4, an acme low in NN5, and top low in NN6.
Plot of occurrence data:
Boesiger, T. M., de Kaenel, E., Bergen, J. A., Browning, E. & Blair, S. A. (2017). Oligocene to Pleistocene taxonomy and stratigraphy of the genus Helicosphaera and other placolith taxa in the circum North Atlantic Basin. Journal of Nannoplankton Research. 37(2-3): 145-175. gs O Denne, R. A. (2008). Utilizing abundance changes of new and non-standard calcareous nannofossil taxa to increase biostra- tigraphic resolution in expanded continental margin deposits: Examples from the Middle and Lower Miocene of the Gulf of Mexico. Transactions of the Gulf-Coast Association of Geological Societies. 58: 227-239. gs Varol, O. (2025). A practical guide to optical studies of calcareous nannofossils. Grzybowski Foundation Special Publication. 29: 1-222. gsReferences:

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Reticulofenestra dennei compiled by Jeremy R. Young, Paul R. Bown, Jacqueline A. Lees viewed: 22-7-2026
Short stable page link: https://mikrotax.org/Nannotax3/index.php?id=20572 Go to Archive.is to create a permanent copy of this page - citation notes |
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