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Rissoa

Rissoa is a genus of minute sea snails, marine gastropod mollusks or micromollusks in the family Rissoidae.

The genus was first introduced by M. de Freminville for some small shells observed by M. Antoine Risso, a distinguished naturalist of Nice, France. They were described by M. Demarest in 1814 in the "New Bulletin of the Philomatic Society".