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Genus Zonomyxa

Shell is large, resting form is discoid, locomotive form is pyriform; chitinoid pellicle, without mucilaginous envelope, flexible, follows the movements of the cell. Surface with small temporal perforations trough which plasma threads emerge. Pseudopods single, clear, conical, from slit-like aperture. Endoplasm granular, violet tinted. Ecology: Sphagnum or aquatic vegetation. Monospecific. Type species: Zonomyxa violacea Greef, 1866