关键词: 熊野藻属, UPA, 系统发育, 地理起源

Abstract: The chloroplast UPA genes were amplified and sequenced for two species in genus Kumanoa from China, including K.intorta(former Batrachospermum intortum) and K.curvata(former B.curvatum), as well as another four Batrachospermum species. The sequences were aligned with related groups from GenBank. Phylogenetic trees were constructed using the methods of Bayesian analysis, maximum likelihood and neighbor-joining. The results showed that the percentages of nucleotide variation sites and parsimony informative sites in UPA are 43.1% and 31.1%, respectively. The species divergence within genus ranges 0-1.81% and between genus is greater than 4.19%, so it is potential to be a molecular barcode to analyze phylogenetic relationships. Two species of Kumanoa from China were clustered together with another species of this genus from across the world, and supported Kumanoa separated from Batrachospermum. The ancestral geographic analysis showed the genus Kumanoa was derived from Eurasia and North America, and then dispersed to other continents with modern geographic advantage in South America.

Key words: Kumanoa, UPA, phylogenetic relationship, ancestral geographic analysis