Citation: Noelaerhabdaceae Jerkovic, 1970 emend. Young & Bown, 1997Rank: FamilySynonyms: Gephyrocapsaceae Black, 1971Taxonomic discussion: The phrase "Noelaerhabdaceaen coccoliths" is ugly and many workers have used alternatives. I reccomend using "reticulofenestrid coccolith" since these all have the same basic structure as Reticulofenestra. Phrases such as "small placoliths" are misleading since unrelated coccolithophores such as Umbilicosphaera produce equally small placoliths. Similarly it is inaccurate to use Isochrysidales to refer to this group unless it is intended to also include both the Prinisaceae and the Isochrysidaceae.
Distinguishing features: Parent taxon (Isochrysidales): 2N: Mostly placolith heterococcoliths with R-unit dominant. Non-motile N: non-calcifying, motile, with vestigial haptonema. This taxon: Heterococcoliths with Reticulofenestra-type structure, V-units vestigal, R-units forming grill, both shields, and two-layered tube
Morphology: Coccoliths are placoliths with Reticulofenestra-type structure, i.e. V-unit vestigial, R-unit forms proximal shield, distal shield, inner and outer tube-cycles, grill and any other central-area structures; strongly birefringent. In the SEM characteristic features include; grill in central area, anti-clockwise imbrication of inner tube elements, and monocyclic proximal shield. References: Young (1989), Young et al. (2004).
Biology & life-cyclesEmiliania huxleyi and Gephyrocapsa oceanica have been cultured extensively and their life-cycle is well worked out (Klaveness 1972, Green et al 1996, Houdan et al. 2004, Frada et al. 2009). The dominant phase is diploid, non-motile and usually heterococcolith-bearing (= C-cells), although naked mutants often occur in culture (= N-cells). The alternate phase is haploid, scale-bearing and motile (= S-cells). There is no holococcolith stage.
Search data:
Lith size: 1->20µm;
The morphological data given here can be used on the advanced search page. See also these notes
Geological Range: Notes: The Noelaerhabdaceae dominate most Neogene nannofossil assemblages with the dominant genera being succesively Cyclicargolithus (NN1-6), Reticulofenestra (NN6-16), Pseudoemiliania (NN16-19), Gephyrocapsa (NN19-20) and Emiliania (NN21). The last occurrences of various larger forms provide excellent highly synchronous biostatigraphic events - particularly LO large R. pseudoumbilicus (end NN10A), LO R. pseudoumbilicus (end NN15), LO large Gephyrocapsa (NN19), LO P. pseudoemiliania (end NN19). Last occurrence (top): Extant. Data source: Total of range of species in this database First occurrence (base): in upper part of Thanetian Stage (62% up, 57.2Ma, in Thanetian stage). Data source: Total of range of species in this database
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
Neptune data: this is a higher taxon page so Neptune data is not plotted. For the customisable plot option go to a genus page Parent: Isochrysidales
References:
Black, M. (1971c). The systematics of coccoliths in relation to the paleontological record. In, Funnell, B. M. & Riedel, W. R. (eds) The Micropaleontology of the Oceans. Cambridge University Press, Cambridge 611-624. gsO
Frada, M., Probert, I., Allen, M. J., Wilson, W. H. & de Vargas, C. (2008). The “Cheshire Cat” escape strategy of the coccolithophore Emiliania huxleyi in response to viral infection. Proceedings of the National Academy of Sciences, USA. 105(41): 15944-15949. gs
Gallagher, L. T. (1989). Reticulofenestra : A critical review of taxonomy, structure and evolution. In, Crux, J. A. & van Heck, S. E. (eds) Nannofossils and their applications: Proceedings of the 2nd INA Conference, London 1987. British Micropalaeontological Society Publication Series . 41-75. gsO
Green, J. C., Course, P. A. & Tarran, G. A. (1996). The life-cycle of Emiliania huxleyi: A brief review and a study of relative ploidy levels analysed by flow cytometry. Journal of Marine Systems. 9: 33-44. gs
Houdan, A. et al. (2004a). Flow cytometric analysis of relative ploidy levels in holococcolithophore-heterococcolithophore (Haptophyta) life cycles. Systematics and Biodiversity. 1(4): 453-465. gs
Jerkovic, L. (1970). Noëlaerhabdus nov. gen. type d'un nouvelle famille de Coccolithophoridés fossiles: Noëlaerhabdaceae du Miocène supérieur de Yugoslavie. Comptes Rendus Hebdomadaires des Séances de l'Académie des Sciences, Paris. 270: 468-470. gs
Klaveness, D. (1972). Coccolithus huxleyi (Lohmann) Kamptner. II. - The flagellate cell, aberrant cell types, vegetative propagation and life cycles. British Phycological Journal. 7: 309-318. gs
Young, J. R. & Bown, P. R. (1997). Cenozoic calcareous nannoplankton classification. Journal of Nannoplankton Research. 19(1): 36-47. gs
Young, J. R. (1989). Observations on heterococcolith rim structure and its relationship to developmental processes. In, Crux, J. A. & van Heck, S. E. (eds) Nannofossils and their applications: Proceedings of the 2nd INA Conference, London 1987. British Micropalaeontological Society Publication Series . 1-20. gs
Young, J. R., Geisen, M., Cros, L., Kleijne, A., Probert, I. & Ostergaard, J. B. (2003). A guide to extant coccolithophore taxonomy. Journal of Nannoplankton Research. S1: 1-132. gs
Young, J. R., Henriksen, K. & Probert, I. (2004). Structure and morphogenesis of the coccoliths of the CODENET species. In, Thierstein, H. R. & Young, J. R. (eds) Coccolithophores - From molecular processes to global impact. Springer, Berlin 191-216. gsO
Noelaerhabdaceae compiled by Jeremy R. Young, Paul R. Bown, Jacqueline A. Lees viewed: 8-6-2023
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