Centropyxis stolata  Bonnet, 1975

Diagnosis: Shell of a simple plagiostome type with axial symmetry and a flat ventral base, without concavity. Shell covering composed of generally reworked siliceous particles, cemented by an abundant, fibrous, chitinoid substance of dark brown color. Pseudostome slightly off-center, approximately circular, without lips or ridges, sealed at rest by a mucous epiphragm, matching the shell in color and blending perfectly with the normal coating. From a dorsal view, circular contour but sometimes showing a slight elliptical tendency. This tendency towards bilateral symmetry is also evident in the presence of an aggregation of siliceous particles firmly attached to the shell, forming a sort of colorless trail.

Dimensions: According to Bonnet (1975): (excluding the particle aggregation) Shell length 95—110 µm; width 85—91 µm; aperture approximately 15 µm.
My measurement on a single shell from Milacka II cave, Croatia (2024): Shell diameter 74 µm; aperture diameter 15 µm.

Ecology: According to Bonnet (1975): Found in moist, alkaline soils rich in organic matter, in gallery forests, backwater areas, on amphibolites. This species coexists with Pseudawerintzewia calcicola. 

Geographical distribution: Region of the Lamto Savanna, Côte d’Ivoire, Africa.
Miljacka II Cave, Krka National Park, Croatia.