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Genus Heleopera

Shell is ovoid, laterally compressed, composed of collected euglyphid body plates, mineral particles or diatoms. These elements are often coated and reinforced with siliceous material. Besides colorless and yellow, several red or purple species are common. Aperture is terminal, lenticular or slit-like, with thin organic rim, with acute notches at edges. Some species have endosymbiotic zoochlorellae. Ecology: freshwater, moss, soil. Type species: Heleopera sphagni (Leidy, 1874)