Cyphoderia laevis Penard, 1902
Diagnosis: shell small, colorless or faintly yellowish, with a rounded fundus; pseudostome circular, relatively large compaired with Cyphoderia ampulla. In cross-section circular or more or less rounded triangular. Faintly curved neck. Nucleus vesicular, granulated, with one or two nucleoli. Filopodia very fine, active.
Dimensions: Penard 35-50 µm; my measurements 41-61 µm.
Ecology: Penard: deep lakes (Lac Léman, Loch Ness) and borders of rivers; marshes.
Remarks: I have seen a few specimens of this small Cyphoderia in a sample from the river Neerbeek in the village of Neer in the southern part of the Netherlands, in the marshes around Kortenhoef and in the Weser river in Germany. A large population was found in an eutrophic ditch near the village of Pingjum in the northern part of the Netherlands, together with Cyphoderia ampulla.