Malawimonas

Malawimonas cells are encountered as naked freeswimming trophic cells and sessile cysts.

Trophic cells are ellipsoidal to pear-shaped (the latter usually when the cells are compressed, as under a cover slip) and between 5 and 12 micrometers long. Two flagella emerge from the anterior end of the cell. The anterior flagellum is free; at rest, the flagellum often projects anteriorly at first and then "hooks back" ventrally.

The posterior flagellum normally remains in a groove that runs longitudinally along the ventral surface of the cell. This groove rarely runs all the way to the posterior end of the cell. The groove is defined by a cytoplasmic vane on the right ventral side of the cell and a short cytoplasmic ridge on the left ventral side of the cell near the flagellar bases. Bacteria are captured in the ventral groove and are digested in food vacuoles. Cells swim in straight lines, rotating along their longitudinal axes. They may also "squirm" along a surface.

Cysts are formed from single trophic cells. They are spherical, with a thin wall probably composed of organic materials and lacking surface ornamentation. They have no aperture visible by light microscopy. They are attached to a substrate by a pad of material.

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