Nannotax3 - ntax_cenozoic - Sphenolithus neoabies

Sphenolithus neoabies

Variant: Sphenolithus neoabies is regarded here as a variant of Sphenolithus abies.
I.e. It is a subjective junior synonym, but some workers many find it useful for some studies (e.g. experienced biostratigraphers working with abundant, well preserved material), but for most purposes differentiating it is not reccomended. Please do use the comments section at the bottom of this page if you wish to discuss this interpretation


Classification: ntax_cenozoic -> Discoasterales -> Sphenolithaceae -> Sphenolithus -> S. moriformis group -> Sphenolithus abies -> Sphenolithus neoabies
Sister taxa: S. bergenii, S. neoabies, S. quadrispinatus, S. verensis

Taxonomy:

Citation: Sphenolithus neoabies Bukry & Bramlette 1969
Rank: Species
Taxonomic discussion: There is no good evidence that separating small sphenolith specimens from larger ones is useful for either biostratigraphy or palaeocology and we do not reccommend use of this taxon. It is, however, fairly widely used, including in database records, so we include it here in the interests of objectivity.
Bergen et al. (2017) use the species but note that it has the same LAD as S. abies. They record an FAD in NN4 at Ceara Rise.

Distinguishing features:
Parent taxon (Sphenolithus abies): Moderately elevated sphenolith with cuspate outline and with extinction line going down long axis of spine.
This taxon: Like S. abies/moriformis but smaller, <4µm & base broad

Farinacci & Howe catalog pages: S. neoabies *


Morphology:


Size:
Bukry & Bramlette proposed a size range of 2-4µm for S. neoabies, Backman proposed a size range of 2-3µm for S. compactus.

Search data:
LITHS: nannolith-radiate, circular, cylindrical, CROSS-POLARS: R-prominent,
Lith size: 2->4µm;
Data source notes: lith height from ODs
The morphological data given here can be used on the advanced search page. See also these notes

Geological Range:
Notes: There have been suggestions that S. neoabies has a slightly higher top in the Pliocene than S. abies. 
Last occurrence (top): within NN15 zone (3.70-3.92Ma, top in Zanclean stage). Data source: commonly recorded up to last occurrence of the genus.
First occurrence (base): within NN4 zone (14.91-17.95Ma, base in Burdigalian stage). Data source: Bergen et al. (2017)

Plot of occurrence data:

References:

Backman, J. (1980). Miocene-Pliocene nannofossils and sedimentation rates in the Hatton-Rockall Basin, NE Atlantic Ocean. Stockholm Contributions in Geology. 36: 1-91. gs O

Bergen, J. A., de Kaenel, E., Blair, S. A., Boesiger, T. M. & Browning, E. (2017). Oligocene-Pliocene taxonomy and stratigraphy of the genus Sphenolithus in the circum North Atlantic Basin: Gulf of Mexico and ODP Leg 154. Journal of Nannoplankton Research. 37(2-3): 77-112. 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 V O

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


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Sphenolithus neoabies compiled by Jeremy R. Young, Paul R. Bown, Jacqueline A. Lees viewed: 30-9-2022

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Short stable page link: https://mikrotax.org/Nannotax3/index.php?id=1306 Go to Archive.is to create a permanent copy of this page - citation notes



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