Sphenoderia quadritesta Stepanek, 1967

Diagnosis: The shape of the shell is similar to that of the species Sphenoderia lenta. The difference is particularly clear in the plates on the surface of the shell. Sphenoderia lenta has plates of elliptical shape, while this species has the same square shape similar to those of the individuals of the genus Quadrulella. Color of the cover is light brown.

Dimensions: Length 38 µm; width 25 µm, aperture 18 µm.

Habitat: Freshwater.

Remarks: Probably the description is based on one specimen.