Detailed morphological studies and molecular analyses based on plastid-encoded rbcL gene sequences were undertaken on Peyssonnelia species, a poorly known genus from Korea. We report new records for the Korean coast, Peyssonnelia harveyana and P. rumoiana. Peyssonnelia harveyana is chiefly characterized by P. rubra-type anatomy, closely packed perithallial filaments in firm matrix, hypothallial filaments arranged in parallel rows, thalli with appressed margins, hypobasal calcification, and unicellular rhizoids. Peyssonnelia rumoiana is principally characterized by two vegetative features, hypothallial filaments arranged in a polyflabellate layer, and perithallial filaments arising from the whole upper surface of each hypothallial cell (Peyssonnelia rubra-type anatomy). Our rbcL analyses revealed that P. harveynana and P. rumoiana were placed within a clade of Peyssonnelia. We also propose the new combination, Sonderophycus cauliferus comb. nov., for previous Peyssonnelia caulifera. Phylogenetic analyses revealed that our S. cauliferus was placed within a clade of Sonderophycus.

• So Young Jeong(Department of Life Science, Chosun University)
• Danilo E. Bustamante(Department of Life Science, Chosun University, Escuela Profesional de Ingieneria Ambiental, Universidad Nacional Toribio Rodriguez de Mendoza (UNTRM))
• Jin Gyo Lee(Department of Life Science, Chosun University)
• Boo Yeon Won(Department of Life Science, Chosun University)
• Seung Hee Kim(Department of Dental Hygiene, Gwangju Health University)
• Tae Oh Cho(Department of Life Science, Chosun University) Corresponding author