Anfractus variabilis
Classification: ntax_mesozoic -> hidden -> deleted -> Anfractus variabilis
Sister taxa: A. variabilis, A. confusa, A. paucipunctata, C. noeliae subsp. depressa, C. noeliae subsp. noeliae, C. noeliae subsp. recondita, Centosphaera, C. barbata, C. ocellatus, C. prinsii, C. deflandrei (morphotype A), C. deflandrei (morphotype B), C. asymmetricus, H. geometricus, M. bramlettei, N. erbae> >>
Distinguishing features: Very small holococcolith with distal surface pierced by 8-10 pores.
Taxonomy:
Citation: Anfractus variabilis Medd, 1979Rank: SpeciesTaxonomic discussion: Lambert (1987) documented great varibility in A. harrisonii and suggested A. variabilis should be considered a synonym/conspecific variant of it.
Farinacci & Howe catalog pages: A. variabilis *
Distinguishing features: Very small holococcolith with distal surface pierced by 8-10 pores.
Size: Type length 1.8 microns.
Search data:
Tags | LITHS: |
Metrics | Lith size: 0->0µm; |
The morphological data given here can be used on the advanced search page. See also these notes
Geological Range:
Last occurrence (top): within Callovian Stage (163.47-166.07Ma, top in Callovian stage). Data source: Medd, 1979
First occurrence (base): within Callovian Stage (163.47-166.07Ma, base in Callovian stage). Data source: Medd, 1979
Plot of occurrence data:
- Range-bar - range as quoted above, pink interval top occurs in, green interval base occurs in.
- Triangles indicate an event for which a precise placement has been suggested
- (NB There is no histogram as there are no occurrence records for the taxon in the Neptune database) Parent: deleted
References:
Medd, A. W. (1979). The Upper Jurassic coccoliths from the Haddenham and Gamlingay boreholes (Cambridgeshire, England). Eclogae Geologicae Helvetiae. 72: 19-109. gs V O