Cyphoderia ampulla  (Ehrenberg, 1840) Leidy, 1879

Diagnosis: Elongated shell with a circular section and rounded bottom. Short neck at a different angle to the shell. Rounded pseudostome with a thin organic layer and teeth around it. Elliptical scales placed next to each other, more or less well aligned. Nucleus large, granular; fine straight filopodia.

Dimensions: Lenghth 89–124 μm, width 33–50 μm, pseudostome large axis 15–25 μm, and scales from the middle of the shell 1.9–2.3 X 1.4-1.8 μm.

Habitat: Freswater sediment, in wet mosses, sphagnum and debris of shallow waters. Also in caves (Croatia).

Remarks: So far a variable species, as the original description covers several hidden species. The drawing made by Ehrenberg, 1840, shows another shell than most specimens labelled as C. ampulla. Ehrenberg’s species has a typical tapering fundus that resembles those of C. calceolus.

I found the specimens below in an eutrophic ditch near Pingjum, in the northern part of the Netherlands, together with many shells of Cyphoderia laevis. All shells had an oval aperture.