Paralieberkuehnia elegantula (Penard, 1904)
Diagnosis: Shell spherical with short tubular neck, composed of organic material, finely granulated, without any embedded xenosomes; hyaline, colorless, older shells yellow till dark-brown. Cytoplasm pear-shaped with an asymmetrical bundle of filopodia (“Pseudopodienstiel”) which are granular (extrusomes), thin, usually very straight, not resting on any substrate, sometimes branching and anastomosing. Nucleus relatively large, globular with a central nucleolus. One or two contractile vacuoles. Division in the shell, a ciliated swarmer leaves the cell.
Dimensions: Penard: 20-25 µm; my measurements: 18-26 µm.
Ecology: Freshwater; shallow, iron rich water, between Sphagnum and in sediments, but also in small rivers and ponds.