I found one specimen in a sample from Kootwijk, the Netherlands. It resembled in its shape and behaviour the German specimen from the river Weser, but the Dutch specimen was much smaller, showed spines and didn't have any reddish color. It moved relatively fast (watch the video below) and disappeared in the debris before I could make better images. The cell is surrounded by a flexible membrane which is covered with many small scales, resembling Cochliopodium species. But this species can be distinguished from Cochliopodium by its oval pseudostome which is flexible and its conical fast moving pseudopodia.
Probably it is the one which has been described by Penard (1904) as Pamphagus bathybioticus (Penardeugenia bathybioticus).