Type Species

Gartnerago? coxalliae Lees, 2007

Etymology

From the Greek "Asynithistos toichos," the unusual wall refers to its bright outer wall.

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.

Description

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.

Remarks

The assignment of Asynithistostoichos to the family Ahmuellerallaceae is questionable due to its single-wall structure, which displays interference colours, a distinctive optical property. 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).

References

Varol, O. 2025a. A practical guide to optical studies of calcareous nannofossils. Grzybowski Foundation Special Publication. 29: 1-222