Locomotive form usualy polytactic, with 3-4 large, well pronounced
pseudopodia. Rapidly moving amoeba may adopt orthotactic form. Morulate
uroid usual. Length in locomotion 457-860 mkm, breadth 57-140 mkm.
Floating form radial, with several thick pseudopodia, containing both
the granuloplasm and the hyaloplasm.
One granular nucleus, discoid, sometimes biconvex, about 40 mkm
in diameter and 15 mkm in thickness. One contractile vacuole. Numerous
bipiramidal cristals and rounded refractile inclusions in the cytoplasm.
No cysts found.
Hexagonal nuclear lamina. Cell coat filamentous, filaments are about 230 nm in lenght.
Mitochondrial heteromorhism is known, however it is not pronounced in the area,
adjacent to the contractile vacuole. Dictyosomes are numerous, each consist
of 5-10 cisternae.