Asynithistostoichos Varol 2025
Original descriptions of 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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Current identification:
Compiled data
Asynithistostoichos Varol 2025
Diagnosis: The loxolith calcareous nannofossils consist of a single wall and a central area with a yoke cycle, creating a bifurcating transverse bar with large pores on both sides. The transverse bar supports a distal process. Optical properties: in the plan view, the wall displays first-order white interference colours, inclined extinction lines and a length-fast (-) elongation. The yoke cycle exhibits first-order whitish-grey interference colours and inclined extinction lines. The distal process shows length-slow (+) elongation in the side view.
Original Description
Etymology:
Extra details from original publication
Remarks: The assignment of Asynithistostoichos to the family Ahmuellerallaceae is questionable due to its single-wall structure displaying interference colours, which are distinctive optical properties. These unique structural and optical characteristics are critical for differentiating Asynithistostoichos from other taxa within the same family. The Ahmuellerallaceae exhibits a single wall with an optical axis perpendicular relative to the microscope stage; therefore, it is in constant extinction (dim).
Varol, O. (2025). A practical guide to optical studies of calcareous nannofossils. Grzybowski Foundation Special Publication. 29: 1-222. gsReferences:

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Asynithistostoichos: Catalog entry compiled by Jeremy Young. Viewed: 16-6-2026
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