LAUSR

Abstract Since its reinstatement, the diversity of the genus Pyropia has never been fully assessed in the Benguela Marine Province in southern Africa (South Africa and Namibia), although it has been included in previous, more general biodiversity assessments. The aim of the present study was to revisit the diversity and identity of species of Pyropia from the region, using an integrative taxonomic approach, including a multigene phylogeny, morphological characterisation and ecological data. The phylogenetic affinities of southern African Pyropia to other species around the world were assessed using three unlinked loci (cox1, rbcL, nSSU rDNA). A species first collected on the South African coast ca. 60 years ago is described as a new species, Pyropia meridionalis, and extended descriptions and further information provided on the distribution and ecology for two previously described species endemic to the Benguela Marine Province: Py. saldanhae and Py. aeodis. Lastly, the identity and occurrence of Py. gardneri, a species widely distributed in North America, could not be confirmed in South Africa, while the cosmopolitan Py. suborbiculata likely occurs in the region but is currently lacking molecular data. The phylogenetic relationships between species from southern Africa and other species occurring in the Southern Hemisphere support the notion of historic connectivity in the Southern Ocean, but also indicate a much more complex historical biogeographical history as some clades are deeply divergent while others are more closely related.