Spumochlamys bryora Kudryavtsev, Pawlowski and Hausmann, 2009
Diagnosis: test with flexible aperture, which may open as wide as ca 0.3–0.8 times the diameter of the test (average 0.6) depending on the physiological condition of the cell. The dorsal part of the test wall consists of the hexagonal alveoles with the cavities connected to each other; the test surface is smooth, with numerous pores; single vesicular nucleus with central nucleolus.
Dimensions: test diameter, 21–30 µm (average 27 mm), diameter of aperture 7–21 µm (average 16 µm) (n=100); pores ca 0.08–0.2 µm in diam. (average 0.13 µm); nucleus 5–6 µm in diam. (average 5.3 µm); nucleolus 2–4 µm in diam. (average 3 µm).