S. conspicuus group


Classification: Coccolithophores -> Discoasterales -> Sphenolithaceae -> Sphenolithus -> S. conspicuus group
Sister taxa: S. capricornutus group, S. dissimilis group, S. moriformis group, S. heteromorphus group, S. predistentus group, S. furcatolithoides group, S. radians group, S. conspicuus group, S. sp.,

Daughter taxa: (blue => in age window 0-800Ma)
Medium sized (height 6.2-9.2 µm) with short to relatively long spine that is slightly asymmetrical and dark at 0°. Square-shaped base with near-equidimensional quadrants and deep spine insertion.
Medium sized (height 5.0-6.7 µm) narrow sphenolith with a tall spine that is dark at 0° and conspicuously bright at 45°. Tall base with long upper quadrants that form part of the spine.
Small to medium sized (height 4.5-7.8 µm) with short spine, broad triangular shape (dart shaped) and wide base in which the lower quadrants dominate. Compound spine is dark at 0°.
Medium-sized sphenolith with a prominent apical spine, extending symmetrically from the basal part.
Large (height 7.5-19.8 µm) narrow sphenolith with a tall spine that is dark at 0°. Relatively tall base, with roughly equidimensional upper and lower quadrants. The spine indents deeply into the upper quadrants, appears to be monocrystalline, and is brightest at 45°.

Taxonomy:

Citation: Sphenolithus conspicuus group
Rank: species group

Distinguishing features: Late Paleocene and Early Eocene sphenoliths with monocrystalline spines

Farinacci & Howe catalog pages:

Search data:
TagsLITHS: nannolith-radiate, N: 3D-radiate, conical, circular, RIM: tiered, PROCESS: length-fast, monocrystalline, spine,
CSPH: not known, V-UNITS: none, R-UNITS: lower-tier, spine, DETAILS: isogyres radial,
MetricsLith size: 4->20µm;
Sources:
The morphological data given here can be used on the advanced search page. See also these notes

Geological Range:
Last occurrence (top): in upper part of Ypresian Stage (67% up, 50.5Ma, in Ypresian stage). Data source: Total of range of species in this database
First occurrence (base): in upper part of Selandian Stage (71% up, 59.9Ma, in Selandian stage). Data source: Total of range of species in this database

Plot of occurrence data:

References:


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S. conspicuus group compiled by Jeremy R. Young, Paul R. Bown, Jacqueline A. Lees viewed: 15-11-2019

Taxon Search:
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Short stable page link: http://mikrotax.org/Nannotax3/index.php?id=1212 Go to Archive.is to create a permanent copy of this page - citation notes



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