Genus Physochila Jung, 1942
Diagnosis: shell pyriform, slightly compressed, surface with indentations and covered with siliceous exogenous plates; aperture more or less circular, with an recurved collar. Nucleus ovular.
Type species: Psysochila griseola (Wailes & Penard, 1911)
Physochila griseola (Wailes & Penard, 1911)
Diagnosis: shell pyriform or ovoid, slightly compressed, mainly of oval or polygonal plates; aperture circular, with an strongly outward curved collar.
Ecology: in Sphagnum swamps, mosses. I have found numerous shells in samples from a peat bog along the Bert Bos path in Loosdrecht, in the central part of the Netherlands, September 2012.
Dimensions: shell 70-85 µm long, mean 75 µm (Deflandre, 1926). My measurements 78-86 µm.
Remarks: If you look carefully at the picture above, you can see that the collar seems to curve inward.