|Daughter taxa: (blue => in age window 0-800Ma)||Granddaughter taxa|
Coccoliths with broad rim and recessed distal cover without boss
BCs with flat distal cover with or without openings; central boss
CFCs; with irregular bridge or distal cover arched upwards
Coccolith distal surface with central boss and varying number of depressions.
BCs flat topped with large openings in tube and variable openings in distal surface; tiered wall fabric; low transverse ridge.
CFCs helladoliths - ridge of BCs is extended into prominent leaf, no openings in tube.
BCs flat topped with node or ridge on distal surface, rather than a true bridge.
CFCs similar with transverse bridge or leaf.
Distinguishing features: Holococcoliths with tube, covered distally by a flat cover
Farinacci & Howe catalog pages: flat-topped [no catalog entry yet]Search data:
|Tags||LITHS: H: cavate,|
|Metrics||Lith size: 1.6->3.3µm; |
Last occurrence (top): Extant Data source: Total of range of species in this database
First occurrence (base): at base of Gelasian Stage (0% up, 2.6Ma, in Gelasian stage). Data source: Total of range of species in this database
Plot of occurrence data:
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