Peronia anomala is a species of air-breathing sea slug, a shell-less marine pulmonate gastropod mollusk in the family Onchidiidae.

[1] It is the most recently discovered species of the genus of Peronia, found in the Red Sea in 1934.

[2] The sea-slug has a small pleural tooth 54μ wide, described by Labbé as "a bit like P. verruclata".

Their size ranged from 10 to 5 mm in length and they have a very contacted body, almost globular.

P. anomala lives in a marine biome sea habitat.