Citation: Discoasteraceae Tan Sin Hok, 1927Rank: Family
Distinguishing features: Parent taxon (Discoasterales): Radially symmetrical nannoliths formed from one to several separate cycles of elements that radiate from a common centre or axis. This taxon: Discoidal discoasteralids formed of one, non-birefringent in plan view, cycle.
Morphology: Discoidal nannoliths of 3-40 elements radiating from a common centre. C-axes vertical, so nannoliths appear dark in plane-polarised light. Size:
Ecology & Biogeography Biology & life-cycles Phylogenetic relationsAlmost certainly evolved from the Heliolithaceae, by loss of the R-units. Disappear from the fossil record at the end of the Pliocene. There is a long term trend in ecology of the group toward reduction of number of elements and increase in space between the elements (Bukry 1971)
Search data:
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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): near top of Gelasian Stage (85% up, 1.9Ma, in Gelasian stage). Data source: Total of range of species in this database First occurrence (base): near base of Thanetian Stage (8% up, 59Ma, 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: Discoasterales
References:
Bukry, D. (1971a). Discoaster evolutionary trends. Micropaleontology. 17: 43-52. gsVO
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
Tan Sin Hok, (1927a). Discoasteridae incertae sedis. Proceedings of the Koninklijke Nederlandse Akademie van Wetenschappen. Sect Sci, 30: 411-419. gsVO
Discoasteraceae compiled by Jeremy R. Young, Paul R. Bown, Jacqueline A. Lees viewed: 8-2-2023
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