informal group Lower Heterobranchia | superfamilia = Valvatoidea | familia = Valvatidae | familia_authority = J. E. Gray, 1840 | synonyms = Borystheniinae Starobogatov, 1983 | diversity_link = | diversity_ref = | diversity = 71 freshwater species }} Valvatidae, the valve snails, is a taxonomic family of very small freshwater snails with an opercul...