Viviparus georgianus (Lea, 1834), (left), and Campeloma linum (Anthony, 1860), (right). Campeloma has the large foot characteristic of active snails that plow through sand just beneath the surface. Both species are native to rivers and streams of the Southeastern United States coastal plain.

Viviparidae, commonly referred to as "mystery snails" have a worldwide distribution. Burch, (1982) list 17 total species for North America. Preston, (1915) lists fourteen for India, Liu Yueyin (1979) includes twelve for China, and Zhadin, (1952) lists five for the territory of the former USSR. They are also present in Australia, Africa and Europe (six species, see Fischer), but except as fossils, absent in South America. The viviparidae are noteworthy in their wide selection of foodstuffs. Brown (1991) indicates they can function both as grazers, consuming algae growing on any submerged surface, and ...

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