Symphyocladia lithophila sp. nov. (Rhodomelaceae, Ceramiales), a new Korean red algal species based on morphology and rbcL sequences

Symphyocladia lithophila sp. nov. is newly described using both morphological and molecular analyses of samples collected from the southeastern coast of Korea. The new species is characterized by small size, ecorticate thallus, with 8–10 pericentral cells, lacking trichoblasts, and having 5–7 segments of congenital fusions. S. lithophila was observed to be a winter species, producing tetrasporangia from December to February. Plastid-encoded rbc L sequences were determined in four samples of S. lithophila from different locations and 21 samples of four putative relatives, including the most related genus Pterosiphonia . All four Symphyocladia lithophila replicates from three different locations had almost identical rbc L sequences, and interspecific sequence divergences were sufficient to warrant its separation as a natural entity. The phylogeny of the rbc L sequences also indicated monophyly of the genus Symphyocladia , which is separated from the genus Pterosiphonia . The specimens of Pterosiphonia , including the type species P. cloiophylla from its type locality in South Africa, form a monophyletic group.