world of amoeboid organisms

from Penard, 1902

Microcorycia penardi (Penard, 1902) Cockerell, 1911

Diagnosis: Upper test part rigid, dome-shaped, with a closed annular collar. The centre of the upper test part and the collar are covered more or less by xenosomes (mineral particles), the size and density of which decrease towards the collar. The upper test part is covered with xenosomes also outside the collar region; their size and density decreases even further towards the test margin where the upper test part gradually changes into the hyaline, xenosome-free lower test part. The upper test part outside the ring is covered with xenosomes only slightly, their size and density decreases towards the upper test part margin. With many individuals, the annular collar shows only a weak development or is completely missing. In the latter case, xenosomes are always circularly arranged. No matter how the upper test part is covered with xenosomes inside or outside the ring, the ring of xenosomes can well be made out. Color of upper test part brownish, also yellowish in the region outside the ring (Penard 1902) and finely punctuate. Digiform lobopodia and epipodia have not been observed. Frequently a widely rotund, lobate pseudopodium is extruded. The cell is mononuclear or binuclear (Penard 1902). The nucleus has got a central nucleolus.

Dimensions: Penard (1902): 100 µm on average, Chardez (1984): 90-110 µm, Badewitz (2004):  X = 99.3 (78-114) µm, n = 16.

Ecology: Terrestrial and limnetic(?) species. Predominantly moss, also sphagnum (Penard 1911, Heinis 1914). The moisture degree of mosses on the locality is usually not detailed. There is only the remark with Bartos (1940) and Badewitz (2003) that the species was found in aerophilic or xerophile mosses.

Remarks: Bartos (1940) reported on “abweichend gebaute Stücke” [differently structured individuals] of M. aculeata that “sehr nahe stehen” [are very similar] to M. penardi. With these individuals, the closed collar has regressed to form individual sharp points, the centre of the upper test part is covered with xenosomes (Fig. 9). It is, however, more probable that this was not M. aculeata, but atypical specimens of M. penardi. Sandon (1924) found it also in soil besides mosses, likewise Balik (1986), who indicated the soil as rendzina. Only Schmassmann (1924) found it in a limnetic habitat (sediment).

All from Badewitz, 2004

Microcorycia penardi
Microcorycia penardi. a = perspective view, b = test in section, c = test with contracted lower test part and upper test part in dorsal view with annularly arranged xenosomes. (Scales 100 µm).
From Badewitz, 2004
Microcorycia penardi
Microcorycia penardi – From Badewitz, 2004
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