Campascus minutus Penard, 1902
Diagnosis: shell broadly ovoid, in cross-section circular; neck cylindroid, strongly curved; fundus rounded; aperture circular, surrounded by a characteristic hyaline collar; shell composed of an organic material, embedded with amorphous, siliceous scales, irregularly arranged; nucleus ovular.
Dimensions: Penard 50-60 µm (mean); my measurements 64-71 µm.
Ecology: fresh water; I found this species in peat bogs in the Laegieskamp and the Naardermeer, both in the Netherlands and in Tirol, Austria. It is apparently of wide geographic distribution, having been reported from Switzerland, Germany, England, Scotland, Czechoslovakia and the U.S.A. (New York).