Peronia is a genus of air-breathing sea slugs, a shell-less marine pulmonate gastropod mollusks in the family Onchidiidae. These slugs differ from other onchidiid slugs in having branched "gills" on their dorsal side, although these can be retracted. More than two dozen species of Peronia have been described from the Indo-West Pacific, but a recent revision of the genus determined that 21 of these names are synonyms. Nine species of Peronia are recognized, most of which can differentiated only by examining their internal anatomy or with DNA sequencing.

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