Algae. 2001; 16(2): 145-150.

Phylogeny of the Family Scytosiphonaceae (Phaeophyta) from Korea based on Sequences of Plastid-encoded RuBisCo Spacer Region

Ga Youn Cho, Hwan Su Yoon, Han-Gu Choi, Kazuhiro Kogame, Sung Min Boo

Department of Biology, Chungnam National University, Division of Biological Sciences, Graduate School of Science, Hokkaido University

The scytosiphonacean brown algae are simple in morphology but complex in life histories. Although the systematics of these taxa has been the focus of recent study, many details remain unresolved. To understand the phylogenetic relationships among these algae, we sequenced the plastid-encoded RuBisCo spacer including the 3'-terminus of rbcL and 5'-terminus of rbcS gene in 22 samples of the family Scytosiphonaceae including Colpomenia bullosa (two locations), C. peregrina (two locations), C. sinuosa, Hydroclathrus clathratus, Petalonia binghamiae (four locations), P. fascia (seven locations), Scytosiphon dotyi, S. gracilis, S. lomentaria (two locations), and Adenocystis utricularis as an out group. Of the 506 nucleotide positions used in the data analyses, 128 sites (25.3%) were variable and 81 sites (16.0%) were phylogenetically informative. All the data analyses showed that the scytosiphonacean algae were comprised of two groups; one included Petalonia, Scytosiphon and Colpomenia bullosa, and the other included Colpomenia sinuosa and Hydroclathrus clathratus. Colpomenia peregrina was basal to other scytosiphonacean representatives. There was no evidence for the monophyly of Colpomenia and Scytosiphon, respectively.

Keywords : brown algae, molecular phylogeny, Phaeophyceae, RuBisCo spacer region, Scytosiphonaceae