Pseudodifflugia senartensis  Coûteaux, 1972

Diagnosis: Shell most often spherical, sometimes slightly elongated along the oral–aboral axis, and yellowish, very pale. Pseudostome barely visible, precisely because of the absence of any differentiation of the covering at its margin. Aperture simple, circular, its diameter slightly smaller than or equal to half the diameter of the test. Very often the pseudostome is invisible. According to Bonnet, it is possible that an epiphragm is present whose conformation would be absolutely identical to that of the test itself. The covering, composed of reworked siliceous elements, coarse and very angular, is very thick—about 5 µm in optical section. This is the most characteristic feature of the species.

Dimensions: Diameter 40 µm; aperture 20 µm.

Ecology: Soil