Difflugia lithophila (Penard, 1902)
Difflugia hydrostatica var. lithophila Penard, 1902
Diagnosis: Shell ovoid with a short distinct neck that forms a small collar;shell in cross-section circular; shell composed of small quartz particles, sometimes mixed with fragments of diatom shells; pseudostome circular, with a somewhat uneven outline.
Dimensions: Penard: length 100-140 µm; my measurements 78-116 µm.
Ecology: I found this species in the sediments of a ditch in the nature reserve Naardermeer, the Netherlands and in a small fen near Kootwijk and in samples from Tirol, Austria.