Two new genera and species of Isopoda Microcerberidea are described: Protocerberus schminkei and Afrocerberus letabai. They are the first Microcerberidea found in Southern Africa and are remarkable in being limnic species with some primitive features (the coxae of P 2-4 are still present, Protocerberus has long uropods) in a group of isopods, which normally live in brackish or marine interstitial waters of sandy beaches.