Distinguishing features: Larger weakly elliptical Calcidiscus species with clearly elliptical central area, opening spanned by a perforated plate.
Original description: Diagnosis: Elliptical species of Calcidiscus with large central area covered by a finely porous plate. Description: This elliptical Calcidiscus has a relatively large central area covered by a finely porous plate. The distal shield and porous plate are non-birefringent where- as the proximal shield is smaller and weakly birefringent under polarised light. No tube cycle was noted. In some specimens, the central porous plate displays a longitudi- nal suture. However, this suture might be the result of poor preservation.
Farinacci & Howe catalog pages: C. gallagheri *
Morphology: Simlar to C. premacintyrei but with plate in central opening, and earlier occurrence
|Tags||LITHS: placolith, elliptical, CA: grill, vacant, |
CSPH: equant, monomorphic, CROSS-POLARS: rim-unicyclic, V-prominent, R-prominent,
|Metrics||Lith size: 10->14µm;|
Last occurrence (top): within NP25 zone (24.40-26.84Ma, top in Chattian stage). Data source: da Gama & Varol 2013
First occurrence (base): within NP25 zone (24.40-26.84Ma, base in Chattian stage). Data source: da Gama & Varol 2013
Plot of occurrence data:
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