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Genus Cryptodifflugia

Shell is oval, egg-shaped, pyriform with a short neck, circular or oval cross-section, with adhering foreign particles or smooth surface, colorless, yellow or brown, composed of an outer proteinaceous material usually lined, aperture terminal, circular or oval. Shell walls of some species with two distinct layers: outer surface is think organic, inner layer thick from calcified material (Hedley et al., 1977). Genus Difflugiella (Cash, 1904) is now considered to by a synonym of Criptodifflugia (Page, 1966). Ecology: freshwater, moss, soil. Type species: Cryptodifflugia oviformis Penard, 1890