Daughter taxa (time control age-window is: 0-800Ma)
Granddaughter taxa
Futyania Very small circular to elliptical placoliths with narrow central area and tube-elements extended distally to form an elevated flower-like distal structure.
Prinsius Prinsiacean placoliths with narrow central areas that are closed or have a narrow opening that may be spanned by a narrow plate/net. Typically very small to medium sized.
Toweius Elliptical to circular prinsiacean placoliths with central areas that are typically spanned by a proximal net and/or distal conjunct nets or bars. Typically medium sized.
Citation: Prinsiaceae Hay & Mohler, 1967 emend. Young & Bown, 1997Rank: FamilyType species: Prinsius Taxonomic discussion: Toweius coccoliths are larger than Prinsius, with wider central areas and therefore more clearly visible central area nets in LM. Similarly, Futyania coccoliths are similar to Prinsius but have distally elevated tube elements.
Distinguishing features: Parent taxon (Isochrysidales): 2N: Mostly placolith heterococcoliths with R-unit dominant. Non-motile
N: non-calcifying, motile, with vestigial haptonema. This taxon: Placoliths with R-units forming the lower layer of proximal shield, inner tube and middle tube; V-units forming an upper layer to the proximal shield, outermost tube and the distal shield. In LM they display a dark outer cycle and brighter inner cycle. Central-area structures are conjunct, formed from the R-units.
Morphology: Typically small to medium sized placoliths with R-units forming the proximal shield-element and two tube-elements, and V-units forming an upper layer to the proximal shield, an outermost tube and the distal shield. In LM they display a dark outer cycle and brighter inner cycle. Central-area structures are conjunct, being formed from either the central-area elements or the inner tube-elements of the proximal shield.
Phylogenetic relations: Toweius gave rise to Reticulofenestra by loss of the V-units - the middle tube cycle of Prinsiaceae forms the outer tube of reticulofenestrids and extends to form the distal shield - see Gallagher (1989) and Young (1989). The similarity of the structures are much clearer in proximal view than distal view.
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Lith size: 1->16µm;
The morphological data given here can be used on the advanced search page. See also these notes
Geological Range: Last occurrence (top): in upper part of Lutetian Stage (74% up, 42.9Ma, in Lutetian stage). Data source: Total of range of species in this database First occurrence (base): at base of Danian Stage (0% up, 66Ma, in Danian 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:
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. gs
Hay, W. W. & Mohler, H. P. (1967). Calcareous nannoplankton from Early Tertiary rocks at Point Labau, France and Paleocene-Early Eocene correlations. Journal of Paleontology. 41(6): 1505-1541. gs
Perch-Nielsen, K. (1985a). Cenozoic calcareous nannofossils. In, Bolli, H. M., Saunders, J. B. & Perch-Nielsen, K. (eds) Plankton Stratigraphy. Cambridge University Press, Cambridge 427-555. gs
Young, J. R. & Bown, P. R. (1997a). Cenozoic calcareous nannoplankton classification. Journal of Nannoplankton Research. 19(1): 36-47. gsVO
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. gsVO
Prinsiaceae compiled by Jeremy R. Young, Paul R. Bown, Jacqueline A. Lees viewed: 28-9-2021
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