Physochila batekensis (Gauthier-Lièvre, 1961) Kosakyan et al. 2023
Basionym: Nebela batekensis Gauthier-Lièvre, 1957

Diagnosis: Shell of small dimensions, ovoid or pear-shaped, compressed; the fundus is either rounded or more or less angular and provided on its edge with 1 to 1 hollow horns, of variable length, straight, wavy or variously curved. In the anterior part the flanks quickly converge towards the pseudostome which appears truncated straight. In reality seen at high magnification, the anterior part tapers into a narrow neck usually formed by large juxtaposed scales; this neck is extended by a chitinoid blade covered with very fine and transparent elements, which suddenly turns outwards and joins the flanks, thus forming an annular collar around the pseudostome. This upturned collar, not very visible in frontal view, is generally clearer in lateral view; in apical view its presence is indisputable: it forms around the aperture of the pseudostome (this one normally oval) a collar 5 to 8 µm wide. The shell is thin, yellowish, light buff or vaguely brownish, hyaline; it is rarely almost colorless and very transparent. This shell is made up of a flexible chitinoid material, more or less covered with generally juxtaposed scales, of very variable dimensions and shapes (rounded, polygonal or irregular).

Dimensions: Length 17-80-90 µm; width 58-63-70 µm; thick 32-36-10 µm; pseudostome with collar 27-30-32 µm; aperture 20-21 X 14-15 µm; spines, 1 to 4, hollow only chitinoid, 6 to 30 long.

Habitat: Aquatic, acidophilic; fairly common in Sphagnum. Middle Congo, Africa.

Remarks: Gauthier-Lièvre distinguishes also a forma ecornis: