Littorinimorpha is a large order of snails, gastropods, consisting primarily of sea snails (marine species), but also including some freshwater snails (limnic species) and land snails (terrestrial species).

Previously, the Linnaean taxonomy used in the taxonomy of the Gastropoda by Ponder & Lindberg (1997) ranked like this: subclass Orthogastropoda, superorder Caenogastropoda, order Sorbeoconcha, suborder Hypsogastropoda, infraorder Littorinimorpha.

The order Littorinimorpha contains many gastropod families that were formerly placed in the order Mesogastropoda, as introduced by J. Thiele in his work from 1921. Evidence for this group being monophyletic is scanty. In 2003, E. E. Strong suggested using only Neogastropoda as a clade within the clade Hypsogastropoda, and to include the unresolved superfamilies of the Hypsogastropoda within the Littorinimorpha.

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