Nannotax3 - ntax_cenozoic - Discoaster quinqueramus

Citation: Discoaster quinqueramus Gartner 1969

Synonyms:

D. quintatus Bukry & Bramlette 1969 [NB A note added in proof in Bukry & Bramlette (1969, p.142) states that D. quintatus is a junior synonym of D. quinqueramus]

Taxonomic discussion: D. bergenii, D. bergrennii and D. quinqueramus form an anagenetic lineage, with central area size decreasing and free ray length increasing. Distinguishing them is useful for determining position within the early part of zone NN11.

Distinguishing features:
Parent taxon (D. quinqueramus group): Symmetric typically 5-rayed, late Miocene discoasters; rays curved proximally, without bifurcations; well-developed distal star and usually proximal boss
This taxon: modest central structures and long free rays

Symmetrical 5-rayed discoaster; central-area, with prominent distal sutural ridges and large proximal boss; rays concavo-convex, with rounded tips. Central area width less than free ray length.

: Highly variable, c.5-15microns.

Geological Range:
Notes: Confined to NN11 (zone defining species). Virtually absent from the Mediterranean and Para-Tethys.
Last occurrence (top): at top of NN11 zone (100% up, 5.6Ma, in Messinian stage). Data source: zonal marker (see e.g. Young 1998)
First occurrence (base): at base of NN11 zone (0% up, 8.3Ma, in Tortonian stage). Data source: zonal marker (see e.g. Young 1998)Young 1998

References:

Bergen, J. A. (1984). Calcareous nannoplankton from Deep Sea Drilling Project Leg 78A: evidence for imbricate underthrusting at the Lesser Antillian active margin. Initial Reports of the Deep Sea Drilling Project. 78A: 411-445. gs

Blair, S. A., Bergen, J. A., de Kaenel, E., Browning, E. & Boesiger, T. M. (2017). Upper Miocene-Lower Pliocene taxonomy and stratigraphy in the circum North Atlantic Basin: radiation and extinction of Amauroliths, Ceratoliths and the D. quinqueramus lineage. Journal of Nannoplankton Research. 37(2-3): 113-144. gs O

Bukry, D. & Bramlette, M. N. (1969b). Some new and stratigraphically useful calcareous nannofossils of the Cenozoic. Tulane Studies in Geology. 7: 131-142. 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

Gartner, S. (1969b). Correlation of Neogene planktonic foraminifera and calcareous nannofossil zones. Transactions of the Gulf-Coast Association of Geological Societies. 19: 585-599. gs

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. (1972). Remarks on Late Cretaceous to Pleistocene coccoliths from the North Atlantic. Initial Reports of the Deep Sea Drilling Project. 12: 1003-1069. 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

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

Wei, W. (2003). Upper Miocene nannofossil bistratigraphy and taxonomy of Exxon core CH30-43-2 from the Gulf of Mexico. Journal of Nannoplankton Research. 25(1): 17-23. gs

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

Sub-taxa & variants (time control age-window is: 0-800Ma)
				forms with modest central structures (D. quinqueramus s.l.)
				Discoaster quintatus Variant with distal star but no proximal knob
				Variants with different number of rays (not usually distinguished)
				Discoaster newellii 3-rayed variant
				Discoaster tetracladus 4-rayed variant
				Discoaster hexaramus 6-rayed variant with short rays
				Discoaster prolixus 6-rayed variant with long rays

Discoaster quinqueramus

References:

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