Molecular analyses reveal the presence of Corynecladia J.Agardh (Rhodophyta, Rhodomelaceae) in the Mediterranean Sea with two new species, C. millarii sp. nov. and C. mediterranea sp. nov.

The findings of this study expanded the geographic distribution of the genus Corynecladia J.Agardh, thought to be endemic to Australia. It is recorded for the first time as present in Europe, with two newly proposed species: C. millarii sp. nov. and C. mediterranea sp. nov. New collections belonging to the Laurencia complex were sampled from the Sicilian coasts of Italy. Examination of this material was carried out using both morphological comparisons and phylogenetic analyses of chloroplast (rbcL) and mitochondrial (COI-5P) nucleotide sequences. The resulting phylogenetic trees divided the Mediterranean specimens into two supported, separate branches, within the genus Corynecladia. Morphological analysis supported placement of these species within Corynecladia and as distinct from other congeners. Specifically, the two new species were conspicuous in the absence of a secondary cortex which is typical of other Corynecladia taxa. Included in this study is a detailed dichotomous key to the Laurencia complex taxa of the Mediterranean.