|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<
Unicyclic, elliptical and circular placolith coccoliths with a narrow or closed central area and a characteristically dark gray (low birefringence) XPL image.
Circular placoliths with moderately birefringent shields, a bright inner tube cycle and narrow or closed central areas.
Narrow rim with thin, imperforate plate across wide central-area.
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.
Farinacci & Howe catalog pages:
Ecology & Biogeography
Biology & life-cycles
|Lith size: 0->0µm; |
Data source notes: size range of included species
Last occurrence (top): in lower part of Rupelian Stage (17% up, 32.9Ma, in Rupelian stage). Data source: Total of range of species in this database
First occurrence (base): in upper part of Tithonian Stage (62% up, 147.7Ma, in Tithonian stage). Data source: Total of range of species in this database
Plot of occurrence data:
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