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Littorinoidea

Littorinoidea are a superfamily of both sea snails and land snails which have a gill and an operculum, terrestrial and marine gastropod mollusks in the clade Littorinimorpha.

The terrestrial family within this group, the Pomatiidae, are sometimes called "land winkles" because the group originated in the sea and the closely related family Littorinidae are known as "winkles".