Assulina discoides Bobrov, Shimano and Mazei, 2012

Diagnosis. Shell large in size, disc shaped, colorless, transparent, narrow-elliptical in cross-section. The width of the shell usually exceeds the length. Aperture is narrow-elliptical with an uneven narrow organic lip. Aperture diameter is about 1/3 of the shell breadth. Surface is covered by large narrow elliptical idiosomes up to 10 µm in length and 5-6 µm in breadth. The population is monomorphic. Variation coefficients of all the morphological characteristics are small.

Dimensions: Bobrov, Shimano and Mazei (2012): Shell length 84—88 µm; width 83—88 µm; breadth 23—27 µm; aperture 26—30 µm.

Ecology: Soil. Mountain pine (Pinus pumila) vegetation; organic surface layer of soil consisting mainly of fallen needles (coniferous semi-decomposed litter – organic surface soils). Mountain gravelly seasonally freezing soils with high moisture content formed on volcanic rocks.

Geographical distribution: Mikuriga-pond, Murodo, Japan.

References: Bobrov. A., Shimano, S., Mazei, Y. (2012). Two New Species of Testate Amoebae from Mountain Forest Soils of Japan and Redescription of the Genus Deharvengia Bonnet, 1979. Acta Protozool. (2012) 51: 55–63.