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Genus Sphenoderia

Scales of one or more types on the main body the shell, aperture slit-like, mostly surrounded by a collar that comprises small scales that can be sometimes invaginated (S. sphaerica). Circular or oval cross section (e.g. S. compressa, S. labiata). Ecology: freshwater, moss, soils. Type species: Sphenoderia lenta Schlumberger, 1845