Living populations of the meso- and supralittoral molluscs Siphonaria pectinata and Echinolittorina punctata are recorded for the Tunisian shores. Siphonaria is most likely to be newly established on this coast, being easily detected and scored as absent in the same sites during previous surveys. The case is unclear for Echinolittorina, for which we do not know any positive published records prior to 1970 but which may have been confused with Melarhaphe neritoides. Both species are of tropical West African affinities and are potentially excellent markers of faunal change in the Mediterranean Sea.
