Distinguishing features: Very large, broadly elliptical with broad, low rim and narrow to closed central opening.
Farinacci & Howe catalog pages: Pontosphaera hollisii *
Morphology remarks: Very large, broadly elliptical pontosphaerid with broad, low rim and narrow to closed central area. The rim is pale grey in cross-polarised light.
Differentiation: Distinguised from other Pontosphaera by larger size, broad rim cycle and low birefringence in cross-polarised light. [Bown & Newsam 2017]
Size: Holotype L = 18.1μm (Paratype L = 18.3μm). [Bown & Newsam 2017]
|Tags||LITHS: murolith, elliptical, RIM: flange-distal, outer wall acw-imbricate, CA: Placoliths: closed-----, closed, |
CSPH: not known, V-UNITS: outer-rim, V-prominent, R-UNITS: all, c-str, distal shield, inner-rim, px-plate, R-prominent, DETAILS: rim-bicyclic, isogyres oblique, isogyres separated,
|Metrics||Lith size: 16->20µm; |
Sources: lith size from OD and slightly extended
Last occurrence (top): within NP15c subzone (42.87-44.12Ma, top in Lutetian stage). Data source: Bown & Newsam 2017
First occurrence (base): within NP15b subzone (44.12-45.49Ma, base in Lutetian stage). Data source: Bown & Newsam 2017
Plot of occurrence data:
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