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Genus Heliamoeba Geisen, Bass & Berney, 2015

Diagnosis: Binucleate, naked amoebae with filose-like pseudopodia. A clearly distinct cell body is always present, the pronounced pseudopodia making up most of thetotal cell dimension. Very rarely branching and if so only slightly, at edges of the cell body; never reticulate. Pseudo-podia are often branching and present mostly in the anterior and posterior parts of fully extended cells, or all around the cell body in more condensed forms. When disturbed under a cover-slip, cells often condense and eventually produce short, round, lobose-like extensions all around the cell body. Cell movement slow but observable under the microscope. Movement occurs at the anterior end, where new pseudopodia are formed. Cysts of regular round shape.
Type species: Heliamoeba mirabilis

Heliamoeba mirabilis Geisen, Bass & Berney, 2015

Diagnosis: Non-marine, with morphological characteristics of the genus. Reaching up to 170 µm in size, cell body up to100 µm in length. Cysts between 10-15 µm in diameter, with two clearly separate walls. Feeds on bacteria, fungi and small flagellates. If detached from the substratum, a distinct floating form is produced with a spherically condensed cell body and numerous radially extending filose pseudopodia (similar to that of Angulamoeba microcystivorans. Amoebae rapidly resume their normal shape and movement whenre-attaching to the substratum.

Ecology: Soil.

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