Reassessment of misapplied names,Phymatolithon feroxandP. repandum(Hapalidiales, Corallinophycidae, Rhodophyta) in South Africa, based on DNA sequencing of type and recently collected material

Two of the four currently recognised species ofPhymatolithonin South Africa areP. repandum(type locality: Half Moon Bay, Port Philip Bay, Victoria, Australia) andP. ferox(type locality: Natal, KwaZulu-Natal, South Africa). PartialrbcL sequences of the lectotype ofP. repandumand the holotype ofP. feroxdemonstrate that the former is not present in South Africa and does not belong inPhymatolithon, whereas the latter belongs inPhymatolithon, but that the name has been misapplied in South Africa. The correct name for the species, currently calledP. repandumin South Africa, isP. ferox. PartialrbcL andpsbA sequences of two of the current heterotypic synonyms ofP. ferox, Lithothamnion prolixumandLithothamnion prolixumf.plicatum, show that they are conspecific and do not belong inPhymatolithon. Lithothamnion prolixumis the basionym for the species currently, but incorrectly, calledP. feroxin South Africa.Phymatolithon repandumandL. prolixumbelong in an as yet undescribed genus. All heterotypic synonyms of currently recognised names of non-geniculate corallines that were placed in synonymy based on morpho-anatomy should not be accepted until confirmed by DNA sequencing.