world of amoeboid organisms

Microcorycia physalis, moss, Germany


Microcorycia physalis (Penard, 1917) Deflandre, 1927

Diagnosis: The upper test part is dome-shaped and has got 5, 6 or 8 radial stiffening ribs. The ribs are differently distinct; they may be slightly intimated to strip-like reinforced. Strip-like reinforced ribs are brown. The upper test part is brown to reddish brown, particularly with older individuals, but grey individuals that are colored like smoked glass or almost hyaline ones occur, too. The upper test part is covered with tiny regular spots, which become visible only at higher magnification (Penard 1917).
According to Penard€™s drawing, the dome-shaped upper test part is extended to form a tip (Penard PI. ll.F ig. 25, and 11.29). The centre of the upper test part is only slightly extended when the ribs are reinforced to a higher degree. The characteristics of M. physalis are highly variable.

Dimensions: Penard (1917): 55-65 µm, Badewitz (2004): mean 60.8 (49-70) µm, n = 21; nucleus 13-14 µm, nucleolus 5-7 µm.

Ecology: Moss, xerophile moss. Europe: Switzerland (Penard 1917), France (Deflandre 1927), Germany (Badewitz 2003).

Remarks: The cytoplasm is greyish and granulate. It contains food particles and excreta as well as contractile vacuoles in varying numbers. Epipodia have not been observed. Digiform pseudopodia are extruded according to Penard (1917), which also serve for locomotion. The cell contains a relatively large cell nucleus with a central nucleolus, which is well visible with many individuals.
Penard (1917) observed division stages. Division is of the transverse type. The test of mother cell can be recognized by its more intensive coloration and distinct costae. The test of daughter cell is, however, hyaline and costae are scarcely visible. Both tests are of the same size.

All from Badewitz, 2004


After Penard, 1917
from Badewitz, 2004
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