Gastropoda, general view on the systematic:

Valvatidae Gray, 1840:

The valvatids (order: Heterostropha, subclass Heterobranchia) are represented by two genera: Cincinna with four non endemic and five endemic species and the endemic genus Megalovalvata with six species (Sitnikova, 1993).

Megalovalvata baicalensis

One species of Cincinna (Cincinna aliena) and four species of  Megalovalvata were investigated on ultrastructural level.