Fissurella mutabilisFissurella mutabilis, common name Cape keyhole limpet, is a species of sea snail, specifically in the family Fissurellidae.DescriptionThe size of the shell reaches 18 mm.DistributionF. mutabilis is commonly found off the coast in Madagascar, Namibia, and South Africa. It is confirmed to be present near Île Amsterdam and Île St. Paul; samples have also been found near the Kerguelen Islands and on the high seas in the South Atlantic.