Nannotax3 - ntax_main - Discoaster deflandrei Nannotax3 - ntax_main - Discoaster deflandrei

Discoaster deflandrei


Classification: ntax_main -> Discoasterales -> Discoasteraceae -> Discoaster -> D. deflandrei group -> Discoaster deflandrei
Sister taxa: D. deflandrei, D. kugleri, D. druggii

Variants (mostly from de Kaenel et al. 2017) (time control age-window is: 0-800Ma)
Discoaster calculosus
broad central area, large (>15 µm) with "broad & shallow inter-ray areas
Discoaster salomonii
broad central area
Discoaster emblematicus
broad central-area, ornate & broadly rounded bifurcation
Discoaster durioi
ornate central-area & angular bifurcation
Discoaster saundersi
ornate central-area & angular bifurcation
Discoaster nephados
short flaring rays & very broad bifurcation
Discoaster leroyi
5-rayed variant of D. deflandrei

Taxonomy:
Citation: Discoaster deflandrei Bramlette & Riedel 1954
Taxonomic rank: species
Basionym: Discoaster deflandrei * Bramlette & Riedel 1954
Taxonomic discussion: The species shows considerable variation in: size, number of rays (5-7), relative size of central area, and degree of development of the ray bifurcations. Hay et al. (1967) used this variation to create 5 separate species, all from the Early Miocene of Trinidad. However, these forms intergrade and separating them has not proven useful. A possible exception are forms with small central areas (D. aulakos, D. saundersii). These become more common toward the end of the Early Miocene, and might be separated as an intermediate variety between D. deflandrei and D. exilis.

Synonyms:
Variants:

Distinguishing features:
Parent taxon (D. deflandrei group): Complanate 6-rayed discoasters with robust bifurcations and smple central-areas
This taxon: 6-rayed discoaster with a well developed central area; rays ending in strong short wide bifurcations.


Morphology:
6-rayed discoaster with a well developed central area; rays ending in strong short wide bifurcations. There is often a distal knob, and sometimes weak distal ridges on the rays. The proximal side is essentially featureless, although the sutures may be incised.

See also: Discoaster distinctus - very similar but bifurcations more angular;Discoaster moorei - asymmetric 5-rayed form. ;

Search data:
LITHS: nannolith-radiate, star-shaped, CROSS-POLARS: 1ou, V-prominent,
Lith size: 8->17µm; Segments: 6->6;
Data source notes: size from OD & illustrated specs
The morphological data given here can be used on the advanced search page. See also these notes

Geological Range:
Notes: In the Middle Miocene D. exilis replaces it as the dominant form. D. deflandrei persists, however, at low abundances; the specimens of this interval show lower variation, with large centred forms dominant.
Last occurrence (top): within NN7 zone (10.89-11.90Ma, top in Tortonian stage). Data source: Young 1998; de Kaenel et al 2017
First occurrence (base): within NP10 zone (54.17-55.86Ma, base in Ypresian stage). Data source: de Kaenel et al 2017

Plot of occurrence data:

References:

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 O

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

Bramlette, M. N. & Riedel, W. R. (1954). Stratigraphic value of discoasters and some other microfossils related to Recent coccolithophores. Journal of Paleontology. 28: 385-403. gs

Bramlette, M. N. & Sullivan, F. R. (1961). Coccolithophorids and related nannoplankton of the Early Tertiary in California. Micropaleontology. 7(2): 129-188. gs

Bukry, D. (1971a). Discoaster evolutionary trends. Micropaleontology. 17: 43-52. gs

de Kaenel, E. & Villa, G. (1996). Oligocene-Miocene calcareous nannofossil biostratigraphy and paleoeecology from the Iberian Abyssal Plain. Proceedings of the Ocean Drilling Program, Scientific Results. 149: 79-145. gs O

de Kaenel, E., Bergen, J. A., Browning, E., Blair, S. A. & Boesiger, T. M. (2017). Uppermost Oligocene to Middle Miocene Discoaster and Catinaster taxonomy and stratigraphy in the circum North Atlantic Basin: Gulf of Mexico and ODP Leg 154. Journal of Nannoplankton Research. 37(2-3): 215-244. gs O

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

Furrazola, G. & Iturralde, M. A. (1967). Estudio micropaleontologico del Oligoceno superior de Cuba, en el Pozo Pijuan No. 47. Revista Tecnologica. 5: 3-11. gs

Gartner, S. (1967a). Calcareous nannofossils from Neogene of Trinidad, Jamaica, and Gulf of Mexico. University of Kansas Paleontological Contributions, Papers. 29: 1-7. gs

Hay, W. W., Mohler, H. P., Roth, P. H., Schmidt, R. R. & Boudreaux, J. E. (1967). Calcareous nannoplankton zonation of the Cenozoic of the Gulf Coast and Caribbean-Antillean area, and transoceanic correlation. Transactions of the Gulf-Coast Association of Geological Societies. 17: 428-480. gs O

Müller, C. (1974). Calcareous nannoplankton, Leg 25 (Western Indian Ocean). Initial Reports of the Deep Sea Drilling Project. 25: 579-633. gs

Perch-Nielsen, K. (1977). Albian to Pleistocene calcareous nannofossils from the Western South Atlantic, DSDP Leg 39. Initial Reports of the Deep Sea Drilling Project. 39: 699-823. gs O

Salomon, R. (1999). The Calcite Palace. Website - https://ina.tmsoc.org/galleries/CalcitePalace/index.htm. -. gs

Self-Trail, J. (2011). Paleogene Calcareous Nannofossils of the South Dover Bridge core, Southern Maryland (USA). Journal of Nannoplankton Research. 32(1): 1-28. gs

Shamrock, J. L. & Watkins, D. K. (2012). Eocene calcareous nannofossil biostratigraphy and community structure from Exmouth Plateau, Eastern Indian Ocean (ODP Site 762). Stratigraphy. 9(1): 1-11. gs

Theodoridis, S. (1984). Calcareous nannofossil biostratigraphy of the Miocene and revision of the helicoliths and discoasters. Utrecht Micropaleontological Bulletin. 32: 1-271. gs O

Varol, O. & Bowman, A. R. (2024). The new Middle Miocene genus Olladiscoaster, and related and associated discoasters. Grzybowski Foundation Special Publication. 28: 1-102. gs

Young, J. R. (1998). Neogene. In, Bown, P. R. (ed.) Calcareous Nannofossil Biostratigraphy. British Micropalaeontological Society Publication Series . 225-265. gs

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Discoaster deflandrei compiled by Jeremy R. Young, Paul R. Bown, Jacqueline A. Lees viewed: 11-9-2026

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Comments (4)

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Shouldn't Discoaster moorei be asymetrical? It is in Perch-Nielsen's description on pg 476 of Plankton Statigraphy.
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I agree. I would just call this a 5 ray D. deflandrei. D. moorei by my concept is much less robust and very asymmetrical.
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hmm - fair call, that is not really an archetypal moorei type specimen. I have never been sure that the 5-rayed asymetric variants are really separate species but in some cases, most obviously D. asymettricus they certainly do have different ranges to the 6-rayed symettric forms. It would be interesting to know how useful people have found  the D. moorei morphotype. Also it would be good to have some photos of better specimens

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I don't see them very often, not even often enough to have a real handle on what kind of range they have. So stratigraphically the species is not useful. On the other hand those I've seen are virtually identical to the one illustrated in P. N. 1984 so I would say with a good degree of confidence that D. moorei should be considered a valid taxon. I don't have a photo, unfortunately.