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Mayorella augusta
Mayorella augusta, 320 µm

Mayorella augusta Schaeffer, 1926

Diagnosis: Locomotive form triangular, with parallel dorsal folds; narrow, with anterior end sometimes divided into two branches, Y-shaped; subpseudopodia usually present; nucleus spherical, with a central somewhat granular nucleolus; cytoplasmic crystals irregular or crystals attached to spherical bodies; many vacuoles; floating form more or less symmetrically, with a number of tapering pseudopodia.

Dimensions: Schaeffer: 250-350 µm; nucleus 18 µm (n=1). My measurements: 200-320 µm, nucleus 19-27 µm, crystals up to 4 µm.

Ecology: Freshwater, in Sphagnum bogs. The amoeba feeds on both algae and protists. It can capture and digest large prey like Difflugia tuberculata, Lesquereusia spiralis and Euastrum oblongum. It can survive for months in samples.

Remarks: Schaeffers description comes from one single specimen.

Mayorella augusta
Mayorella augusta
Mayorella augusta, crystals, and nucleus, 24 µm.
Mayorella augusta crystals
Mayorella augusta crystals
Mayorella augusta, crystals attached to spherical bodies.
Mayorella augusta
Mayorella augusta, dorsal folds.
Mayorella augusta
Mayorella augusta, splitting in Y-shape.
Mayorella augusta
A: Locomotive form; B: With large diatom; C: With Lesquereusia spiralis; D: Nuclei; E: Crystals; H: amoeba with Euastrum oblongum; F: Narrow locomotive form; G: Floating form (Drawings: Ferry Siemensma, 1987
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