First record of fertile gametophytes of Polysiphonia perforans (Ceramiales, Rhodophyta)

We report fertile gametophytes of Polysiphonia perforans for the first time in collections from the Mediterranean Sea. The occurrence of spermatangial axes replacing whole trichoblasts and four-celled carpogonial branches, in addition to the previously known features, such as the occurrence of four pericentral cells, the open connection between rhizoids and pericentral cells and the straight arrangement of tetrasporangia, allow us to confirm that the species belongs to the genus Polysiphonia