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Genus Antarcella

Shell is circular in frontal view, hemispherical in lateral view, aperture is circular, invaginated. In contrast to Arcella, Antarcella has one ovular nucleus. Contractive vacuole 10 to 15 µm in diameter. To distinguish Antarcella species from Arcella spp., staining of the nucleus is recommended. Ecology: Sphagnum mosses. Two species. Type species: Antarcella atava (Collin, 1914)