world of amoeboid organisms

Pterocystis echinata
R. echinata – from Siemensma, 1991

Raineriophrys echinata (Rainer, 1968) Mikrjukov, 2000

Diagnosis: Cells with a diameter of 25-30 µm. Spine-scales 10-20 µm, with a strongly bent shaft, sub-centrally attached to a more or less circular or coniform basal plate. Laterally two small triangular wings connect the basal part of the shaft to the membrane. Both wings extend along the whole shaft as two narrow bands, ornamented with a small number of sharply pointed teeth. The plate-scales are oblong ovoid, 4.7 to 8.0 x 2.2-3.4 µm. The upper surface is slightly convex, the lower surface concave with a longitudinal rod-like axial protrusion. Surface structure smooth.

Ecology: Fresh waters, in Germany, The Netherlands, Central Russia.
I found this species several times in water with Sphagnum contact (Laegieskamp and Fochteloërveen) and also together with Acanthocystis dresscheri in a small moorland pool, pH 5.5, all in the Netherlands.

Pterocystis echinata
R. echinata, cyst, 20 µm
Raineriophrys echinata
Dried spine-scales showing the teeth on the shafts (arrowed)
Rainerophrys echinata
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