Phylogeography of rose bitterling, Rhodeus ocellatus (Kner, 1866) (Actinopterygii: Cyprinidae), in East Asia

• Main Authors: Yao-Fong Tsao, 曹耀峰
• Other Authors: 高孝偉
• Format: Others
• Language: en_US
• Published: 2012
• Online Access: http://ndltd.ncl.edu.tw/handle/7sr33w

碩士 === 國立中興大學 === 生命科學系所 === 100 === Abstract The rose bitterling, Rhodeus ocellatus, is a small cyprinid fish that distributed in East Asia. It consists of 2 subspecies: R. o. ocellatus and R. o. kurumeus. According to the previously study, the freshwater fish in China can be classified into 5 biogeographic regions, including Northeastern China, Eastern China, Southern China, Northwestern China, and Southwestern China region. Taiwan is included in Southern China region. In this study, I proposed that the phylogeographic pattern of R. ocellatus in East Asia is congruent with the classification of biogeographic regions of freshwater fish in China, and, R. o. ocellatus and R. o. kurumues were sister groups. To test this hypothesis, the specimens from China, Japan, and Taiwan were collected. I conducted phylogenetic analyses of cytochrome b (cyt b) DNA sequences by using Bayesian inference and maximum likelihood methods. Furthermore, I used inter-simple sequence repeats (ISSRs) to infer the genetic structure and admixture of R. ocellatus among different regions. Phylogenetic tree showed that R. ocellatus in East Asia can be divided into 6 mtDNA clades (clade A-F). Clade A included 3 specimens from Southern China that was located at the basal position of the tree. Clade B included the specimens from Eastern China region. Clade C included the specimens form Eastern China and Southern China region. These 2 clades were further clustered together to form a monophyletic groups. Clade D included the specimens from Japan. Clade E included the specimens from Taiwan. Clade F included the specimens from Northeastern China, Eastern China, and Japan region. These 3 clades were further clustered together to form a monophyletic group. Among these clades, clade E had a closer relationship with clade F than clade D. Specimens from Eastern China regions were composed of those from 3 mtDNA clades, suggesting that multiple dispersal events might occur in this region. The result of Bayesian assignment test showed that the existence of genetic admixture in Jinan, Shandong in East China and Japan region. Because each biogeographic region comprised 2 or 3 mitochondrial clades in the phylogenetic tree, the phylogeographic pattern of R. ocellatus was not consistent with the hypothesis of biogeographic regions of freshwater fish in China. I proposed that the phylogeography of R. ocellatus in East Asia might be resulted from multiple dispersal events from scattered glacial refugia in the Quaternary glaciation. The potential refugia for R. ocellatus included southern coast of China, eastern coast of China, Japan, and Taiwan. The multiple dispersal events might occur in Eastern China region.