Nannotax3 - ntax_mesozoic - Tegumentum lucidum Nannotax3 - ntax_mesozoic - Tegumentum lucidum

Tegumentum lucidum


Classification: ntax_mesozoic -> Eiffellithales -> Eiffellithaceae -> Tegumentum -> Tegumentum lucidum
Sister taxa: T. lucidum, T. octiformis, T. stradneri, T. sp.

Distinguishing features:
Parent taxon (Tegumentum): Murolith (loxolith) coccoliths with a prominent inner rim cycle that is birefringent and conspicuous in cross-polarised light. This cycle is broader than the outer rim cycle. The central area is spanned by curving, diagonal cross-bars.
This taxon: Medium-sized, murolith coccolith with a broad bicyclic rim, dominated by the thick, bright inner cycle, and a narrow, central area almost filled by short, broad, bright diagonal cross bars.


Taxonomy:

Citation: Tegumentum lucidum Lees & Bown, 2005
taxonomic rank: Species

Farinacci & Howe catalog pages: T. lucidum *

Distinguishing features:
Parent taxon (Tegumentum): Murolith (loxolith) coccoliths with a prominent inner rim cycle that is birefringent and conspicuous in cross-polarised light. This cycle is broader than the outer rim cycle. The central area is spanned by curving, diagonal cross-bars.
This taxon: Medium-sized, murolith coccolith with a broad bicyclic rim, dominated by the thick, bright inner cycle, and a narrow, central area almost filled by short, broad, bright diagonal cross bars.


Morphology:

The rim of this coccolith is highly distinctive, having a broad, bright (white) inner cycle and a very narrow, dark, outer cycle. The LM appearance is most reminiscent of Tegumentum, but is also similar to Eiffellithus. The broad, rounded, diagonal cross bars almost fill the narrow central area and are of similar birefringence to the inner rim cycle. Differentiated from other species of Tegumentum by its narrower central area and broad, rounded cross bars. Somewhat similar to the Early Cretaceous Eiffellithus windii but the cross bar morphology is distinct and outer rim cycle narrower.

Size:
Length 5.0-6.5µm

Search data:
LITHS: murolith, elliptical, CA: ca_disjunct, diagonal cross, closed, CROSS-POLARS: rim-bicyclic, R-prominent,
Lith size: 5->7µm;
Data source notes: original description & illustrated specimens
The morphological data given here can be used on the advanced search page. See also these notes

Geological Range:
Last occurrence (top): within Late Maastrichtian Substage (66.04-70.10Ma, top in Maastrichtian stage). Data source: Lees & Bown 2005
First occurrence (base): within Early Campanian Substage (80.60-83.65Ma, base in Campanian stage). Data source: Lees & Bown 2005

Plot of occurrence data:

References:

Lees, J. A. & Bown, P. R. (2005). Upper Cretaceous calcareous nannofossil biostratigraphy, ODP Leg 198 (Shatsky Rise, Northwest Pacific Ocean). Proceedings of the Ocean Drilling Program, Scientific Results. 198: 1-60. gs


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Tegumentum lucidum compiled by Jeremy R. Young, Paul R. Bown, Jacqueline A. Lees viewed: 23-4-2024

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Short stable page link: https://mikrotax.org/Nannotax3/index.php?id=11199 Go to Archive.is to create a permanent copy of this page - citation notes
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