Sphenolithus bipedis


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

Taxonomy:

Citation: Sphenolithus bipedis Bergen & de Kaenel, in Bergen et al. 2017
Rank: species
Synonyms:

Distinguishing features: Hemispherical with a flared proximal cycle and arcuate proximal surface

Farinacci & Howe catalog pages: S. bipedis *


Morphology:

Very small to medium hemispherical sphenolith having a compound apical spine. Proximal cycle is laterally-extended or “flared”, resulting in height to width ratios of less than 1 (0.81–0.91 for five mea- sured specimens). Proximal surface strongly concave and arcuate. [Bergen et al 2017]

S. neoabies is a younger and generally smaller version of S. bipedis. Their stratigraphic ranges are separated by approximately 1.58 million years in the ODP Leg 154 materials. The proximal surface of S. bipedis is more arcuate than the more linear and less concave proximal surface of S. neoabies. Other hemispherical sphenoliths do not possess a flared proximal cycle. S. bipedis has been referred to as “S. delphix (no stem)” in the BP GoM lexicon. [Bergen et al 2017]


Size: 2.8–6.4 µm [Bergen et al 2017]

Search data:
TagsLITHS: nannolith-radiate, circular, cylindrical, CROSS-POLARS: R-prominent,
MetricsLith size: 2.8->6.4µm;
Data source notes: Bergen et al 2017
The morphological data given here can be used on the advanced search page. See also these notes

Geological Range:
Last occurrence (top): within NN3 zone (17.95-19.00Ma, top in Burdigalian stage). Data source: Bergen et al 2017
First occurrence (base): within NP24 zone (26.84-29.62Ma, base in Rupelian stage). Data source: Bergen et al 2017

Plot of occurrence data:

References:

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 V O


nannotaxlogo400px

Sphenolithus bipedis compiled by Jeremy R. Young, Paul R. Bown, Jacqueline A. Lees viewed: 13-4-2021

Taxon Search:
Advanced Search

Short stable page link: https://mikrotax.org/Nannotax3/index.php?id=1616 Go to Archive.is to create a permanent copy of this page - citation notes



Comments (0)

No comments yet on this page. Please do add comments if you spot any problems, or have information to share

Add Comment

* Required information
1000
Captcha Image
Powered by Commentics