Nannotax3 - ntax_mesozoic - placoliths inc sedis Nannotax3 - ntax_mesozoic - placoliths inc sedis

placoliths inc sedis

Classification: ntax_mesozoic -> Heterococcoliths inc sedis -> placoliths inc sedis
Sister taxa: Papposphaeraceae, Unidentified Mesozoic heterococcoliths, globular inc sedis, muroliths inc sedis, placoliths inc sedis, planoliths inc sedis

Daughter taxa (time control age-window is: 0-800Ma)Granddaughter taxa
Elongate, rounded-oblong placoliths with unicyclic distal shields built of numerous (>50) narrow elements<
Ellipsolithus linnertii

Unicyclic, elliptical and circular placolith coccoliths with a narrow or closed central area and a characteristically dark gray (low birefringence) XPL image.
Haqius circumradiatus
Haqius ellipticus
Haqius peltatus
Haqius sp.

Circular placoliths with moderately birefringent shields, a bright inner tube cycle and narrow or closed central areas.
Markalius inversus
Markalius vetulus
Markalius sp.

Narrow rim with thin, imperforate plate across wide central-area.
Prolatipatella multicarinata
Prolatipatella sp.

Placoliths with monocyclic distal shield with numerous, narrow elements and central-area spanned by ~20 radial bars. In LM the coccoliths are distinctive but inconspicuous with low birefringence, "flaring" image.
Repagulum parvidentatum
Repagulum sp.


Citation: placoliths inc sedis
taxonomic rank: Family

Farinacci & Howe catalog pages:

Search data:
Lith size: 0->0┬Ám;
Data source notes: size range of included species
The morphological data given here can be used on the advanced search page. See also these notes

Geological Range:
Last occurrence (top): at top of NP21 zone (100% up, 32.9Ma, in Rupelian stage). Data source: Total of ranges of the species in this database
First occurrence (base): within Late Tithonian Substage (145.01-147.72Ma, base in Tithonian stage). Data source: Total of ranges of species in this database

Plot of occurrence data:



placoliths inc sedis compiled by Jeremy R. Young, Paul R. Bown, Jacqueline A. Lees viewed: 4-12-2023

Taxon Search:
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Short stable page link: Go to to create a permanent copy of this page - citation notes

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