Pompholyxophrys stellata Nicholls and Dürrschmidt, 1985

Diagnosis: Scales oblong or ovoid, 1.6 – 3.5 x 3.0 – 5.4 µm, hollow, constructed of two hemispherical domes joined by a continuous thickened rib, 0.05 µm in diameter, around the circumference of the scale. Scale ornamented with pores (0.05 µm in diameter) arranged in rows, 10 pores per 1 µm. The upper and lower surfaces of the scales are ornate with 3 – 4 concentric rows of stellate structures 0.3 – 0.5 µm in diameter, absent from the central area of the scale.

Habitat: I found this species in freshwater bodies in the Netherlands and Sweden. Nicholls and Dürrschmidt (1985) report this species from Canada and Chili. Steffen Clauss isolated specimens from the Rotes Wasser, Germany (pers. comm.).

Remarks: Nicholls and Dürrschmidt notice that they have found “only broken periplasts and single scales (…) Details of the protoplast are not known; no living specimens have been seen.”