world of amoeboid organisms


Mayorella bigemma (Schaeffer, 1918)

Diagnosis: Locomotive form fairly broad triangular, with sometimes parallel dorsal folds; subpseudopodia usually present; nucleus spherical, with a central nucleolus; cytoplasmic crystals attached to spherical bodies or paired; floating form with long radiate pseudopodia.

Dimensions: Page: 100-300 µm; nucleus 12 µm. My measurements: 85-190 µm, nucleus 14.4-17.5 µm.

Ecology: Freshwater, in Sphagnum bogs.

Remarks: The name “bigemma” refers to the typical paired crystals, attached to spherical bodies. These crystals however are not characteristic for this species.

A-C: Locomotive form; D: Crystals; E: Nucleus. (F-H: Acanthamoeba spec.) (Drawings: Ferry Siemensma, 1987)
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