Nannotax3 - ntax_cenozoic - Sphenolithus primus

Sphenolithus primus


Classification: ntax_cenozoic -> Discoasterales -> Sphenolithaceae -> Sphenolithus -> S. moriformis group -> Sphenolithus primus
Sister taxa: S. abies, S. apoxis, S. moriformis ⟩⟨ S. grandis, S. puniceus, S. acervus ⟩⟨ S. primus

Taxonomy:

Citation: Sphenolithus primus Perch-Nielsen 1971
Rank: Species

Taxonomic discussion:
In the original descrpition of Perch-Nielsen (1971) - it is described as having a dome-shaped ("kuppelformigen") opening on proximal side instead of the usual conical ("trichterformigen") opening. However, since the material studied was clearly overgrown this distinction seems dubious. In practice S. primus is used for all Palaeocene sphenoliths - and the images given here include specimens originally identified as Sphenolithus sp. Separation from S. moriformis in the Early Eocene seem to be subjective. [my interpretation - JRY 2021]

Distinguishing features:
Parent taxon (S. moriformis group): Conical and hemispherical sphenoliths without prominent apical spines.
This taxon: Small with dome-shaped opening on proximal side

Farinacci & Howe catalog pages: S. primus *


Morphology: A small sphenolith with a medium-height, slightly conical proximal element cycle, thin lower and upper lateral element cycles, and polycyclic composite apical element cycles forming a low apical dome. [Howe 2021]


Phylogenetic relations: This is the first Sphenolithus species and is assumed to be the ancestral form.

Most likely ancestor: Diantholitha mariposa - at confidence level 3 (out of 5). Data source: Aubry et al. 2011, Howe 2021.
Likely descendants: Sphenolithus acervus; Sphenolithus anarrhopus; Sphenolithus editus; Sphenolithus moriformis; plot with descendants

Search data:
TagsLITHS: nannolith-radiate, circular, cylindrical, CROSS-POLARS: R-prominent,
MetricsLith size: 3->6µm;
Data source notes: lith height from illustrated specs
The morphological data given here can be used on the advanced search page. See also these notes

Geological Range:
Notes: Not easily separated from S. moriformis so probably not of practical biostratigraphic use
Last occurrence (top): within NP11 zone (53.70-54.17Ma, top in Ypresian stage). Data source: Perch-Nielsen 1985
First occurrence (base): in upper part of NP4 zone (70% up, 62Ma, in Danian stage). Data source: Monechi et al. 2013, fig 5; Varol, 1989, fig. 12.4 (Varol places it slightly higher in NP4)

Plot of occurrence data:

References:

Aubry, M. P., Bord, D. & Rodriguez, O. (2011). New taxa of the Order Discoasterales Hay 1977. Micropaleontology. 57(3): 269-287. 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 V O

Bybell, L. & Self-Trail, J. (1997). Late Paleocene and Early Eocene calcareous nannofossils from three boreholes in an onshore-offshore transect from New Jersey to the Atlantic continental rise. Proceedings of the Ocean Drilling Program, Scientific Results. 150: 91-110. gs V O

Howe, R. (2021). Ultrastructure and taxonomy of the family Sphenolithaceae. Journal of Nannoplankton Research. 39(1): 29-75. gs

Monechi, S., Reale, V., Bernaola, G. & Balestra, B. (2013). The Danian/Selandian boundary at Site 1262 (South Atlantic) and in the Tethyan region: Biomagnetostratigraphy, evolutionary trends in fasciculiths and environmental effects of the Latest Danian Event. Marine Micropaleontology. 98(1): 28-40. gs

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

Okada, H. & Thierstein, H. R. (1979). Calcareous nannoplankton - Leg 43, Deep Sea Drilling Project. Initial Reports of the Deep Sea Drilling Project. 43: 507-573. gs V O

Perch-Nielsen, K. (1971b). Einige neue Coccolithen aus dem Paläozän der Bucht von Biskaya und dem Eozän der Labrador See. Bulletin of the Geological Society of Denmark. 21: 347-361. gs V O

Perch-Nielsen, K. (1972b). Remarks on Late Cretaceous to Pleistocene coccoliths from the North Atlantic. Initial Reports of the Deep Sea Drilling Project. 12: 1003-1069. gs V O

Perch-Nielsen, K. (1977a). 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 V O

Perch-Nielsen, K. (1985a). Cenozoic calcareous nannofossils. In, Bolli, H. M., Saunders, J. B. & Perch-Nielsen, K. (eds) Plankton Stratigraphy. Cambridge University Press, Cambridge 427-555. gs

Steurbaut, E. & Sztrákos, K. (2008). Danian/Selandian boundary criteria and North Sea Basin–Tethys correlations based on calcareous nannofossil and foraminiferal trends in SW France. Marine Micropaleontology. 67: 1-29. gs

Varol, O. (1989c). Palaeocene calcareous nannofossil biostratigraphy. In, Crux, J. A. & van Heck, S. E. (eds) Nannofossils and their applications: Proceedings of the 2nd INA Conference, London 1987. British Micropalaeontological Society Publication Series. 265-310. gs V O


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Sphenolithus primus compiled by Jeremy R. Young, Paul R. Bown, Jacqueline A. Lees viewed: 29-9-2021

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Short stable page link: https://mikrotax.org/Nannotax3/index.php?id=1313 Go to Archive.is to create a permanent copy of this page - citation notes



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