Distinguishing features:
Parent taxon (Biscutaceae): Regular placoliths; rim broad, central area relatively narrow, with variable central structures.
The distal shield is formed from V-units and the proximal shield and tube cycle are formed from R-units.
This taxon: Elliptical, large with broad shields; central area wide, spanned by a granular plate.
Daughter taxa (time control age-window is: 0-800Ma)![]() | ||||
Gaarderella granulifera Large placolith with broad shields and wide central area spanned by a granular central-area plate. | ||||
![]() | Gaarderella sp. Specimens not identified to species level |
Taxonomy:
Farinacci & Howe catalog pages: Gaarderella *
Distinguishing features:
Parent taxon (Biscutaceae): Regular placoliths; rim broad, central area relatively narrow, with variable central structures.
The distal shield is formed from V-units and the proximal shield and tube cycle are formed from R-units.
This taxon: Elliptical, large with broad shields; central area wide, spanned by a granular plate.
Morphology:
Size:
Tags | LITHS: placolith, elliptical, CA: plate, CROSS-POLARS: rim-bicyclic, V-prominent, R-prominent, |
Metrics | Lith size: 8->12µm; Data source notes: size range of included species |
Geological Range:
Last occurrence (top): at top of Albian Stage (100% up, 100.5Ma, in Albian stage). Data source: Total of range of species in this database
First occurrence (base): at base of Albian Stage (0% up, 113Ma, in Aptian stage). Data source: Total of range of species in this database
Plot of occurrence data:
Black, M. (1973). British Lower Cretaceous Coccoliths. I-Gault Clay (Part 2). Palaeontographical Society Monograph. 127: 49-112. gs Bown, P. R., Rutledge, D. C., Crux, J. A. & Gallagher, L. T. (1998). Lower Cretaceous. In, Bown, P. R. (ed.) Calcareous Nannofossil Biostratigraphy. British Micropalaeontological Society Publication Series. 86-131. gs OReferences:
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Gaarderella compiled by Jeremy R. Young, Paul R. Bown, Jacqueline A. Lees viewed: 6-7-2022
Short stable page link: https://mikrotax.org/Nannotax3/index.php?id=10454 Go to Archive.is to create a permanent copy of this page - citation notes |
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