First record of Neoporphyra haitanensis (T.J.Chang & B.F.Zheng) J.Brodie & L.‐E.Yang (Bangiales, Rhodophyta) from Shikinejima Island and Hachijojima Island of the Izu Islands, southern central Japan

We conducted a morphological observation and molecular phylogenetic analyses on bladed Bangiales collected from natural populations on Shikinejima Island and Hachijojima Island of the Izu Islands, southern central Japan. The morphological features of the gametophytic blades such as the blade shape, blade margin and reproductive cell divisions were extremely similar to those parameters of Neoporphyra haitanensis, a species cultivated in southern China, and Neoporphyra dentata. However, the blades collected from the two islands were thicker than the blades of N. dentata; this feature was the same as that of N. haitanensis. The chloroplast RUBISCO spacer sequences of present samples were identical to the sequences of N. haitanensis from China. Moreover, phylogenetic positions of three conchocelis strains isolated from the blades on the two islands were examined based on concatenated sequences of the chloroplast rbcL gene and nuclear 18S rRNA. The results showed that the strains were resolved in a clade including N. haitanensis; however, the strains were separated from N. haitanensis in China. Therefore, the bladed Bangiales from the two islands were identified as N. haitanensis. The present study is the first record of N. haitanensis in natural populations in Japan.