Pseudodifflugia virescens Penard, 1904

Diagnosis: shell chitinoid, yellow to brownish, pyriform, broad elliptical, not compressed, covered with minute particles; shell wall relatively thick; aperture circular; plasma body clear visible despite the thick covering of the shell; plasma body not completely filling the shell; nucleus large, with a small central nucleolus; filopodia numerous, long and straight, branching, but not anastomosing.

Dimensions: Penard c. 36 µm long and 26 µm broad. My measurements: 38-43 µm long.

Ecology: Sphagnum, aquatic plants and sediments. Fresh water.

Remarks: Penard (1904) mentions the presence of zoochlorellae in all observed cells (“plasma toujours rempli de globules chlorophylliens”) I have never seen zoochlorellae in any Pseudodifflugia species.