Original descriptions of taxa - also emended descriptions for a few taxa. For coccolithophores, and many calcispheres, these are pages from the Farinacci & Howe Catalog of Calcareous Nannofossils. In other cases (e.g. non-calcifying haptophytes) the data is directly compiled on this site. The "Catalogue of Calcareous Nannofossils" was originally compiled by Prof A. Farinacci 1969-1989, since 2000 it has been updated and extended by Richard Howe - see The Farinacci and Howe Catalog - an Introduction.
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![]() | Sikoraea steinhaueri Varol & Bowman 2019 = Sikoraea steinhaueri |
Current identification/main database link: Sikoraea Varol & Bowman 2019
Compiled data
Original Description
Description: Sikoraea is birefringent in both plan and side views and has an axial (radial) c-axis, which is parallel to the length of the nannolith. In side view, species are elliptical with the longitudinal slits confined to its apex. The slits do not extend to the lateral axis. In plan view, species are subcircular to circular, with eight radiating ridges. The ridges alternate between narrow and wider sizes. The narrow ridges interlock into slits but are not usually visible in side view.
Etymology:
Extra details from original publication
Varol, O. & Bowman, A. R. (2019). Taxonomic revision of selected Late Jurassic (Tithonian) calcareous nannofossils and the application of mobile mounting. Neues Jahrbuch für Geologie und Paläontologie, Abhandlungen. 291: 65-87. gsReferences:

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Sikoraea: Catalog entry compiled by Jeremy Young. Viewed: 15-8-2026
Short stable page link: https://mikrotax.org/Nannotax3/index.php?id=55288 Go to Archive.is to create a permanent copy of this page - citation notes |