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 with several distinct cycles including at least one that is birefringent.
Farinacci & Howe catalog pages:
Heliolithaceae *
| Lith size: 5->18µm; |
Geological Range:
Last occurrence (top): at top of NP9b subzone (100% up, 55.9Ma, in Ypresian stage). Data source: Total of ranges of the species in this database
First occurrence (base): within Paleocene Epoch (55.96-66.04Ma, base in Danian stage). Data source: Total of ranges of species in this database
Plot of occurrence data:
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. gsReferences:

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Heliolithaceae compiled by Jeremy R. Young, Paul R. Bown, Jacqueline A. Lees viewed: 12-4-2026
Short stable page link: https://mikrotax.org/Nannotax3/index.php?id=697 Go to Archive.is to create a permanent copy of this page - citation notes |
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