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Leptophrys elegans
Arboramoeba reticulata, photomicrograph Eckhard Voelcker

Genus Arboramoeba Geisen, Bass & Berney, 2015

Diagnosis: Multinucleate, highly branching and reticulate naked amoebae. Cell body not really distinct; nuclei and other cell contents are distributed across the whole network. The network is significantly more complex at the anterior front, forming a wide, very densely reticulate, non-permeable frontier where prey phagocytosis occurs, leaving behind a nearly sterile zone as the cell moves forward. The posterior part of the cells is much less reticulate and branching, with one or few non-branching, non-filose posterior endings. Branching, filose-like, pseudopodia are mostly present at the anterior front of the cell, but can also be found in other parts of the network, regularly fusing with other parts of the cell. Very strong vacuolar activity across the whole network. Movement of entire cells too slow to be directly observable. No distinct floating form was observed; cells retain their complex shape when carefully detached from the substratum. Cysts with two clearly separate walls varying both in size and shape (never perfectly round, often ovoid).
Type species: Arboramoeba reticulata

Leptophrys elegans
Photomicrograph Eckhard Voelcker – from Sphagnum, Germany
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