Molecular Phylogeny and Genetic Differentiation of the Tanakia himantegus Complex (Teleostei: Cyprinidae) in Taiwan and China

Chia-Hao Chang, Wen-Wen Lin, Yi-Ta Shao, Ryoichi Arai, Toshilhiro Ishinabe, Takayoshi Ueda, Masaru Matsuda, Hitoshi Kubota, Feng-Yu Wang, Nian-Hong Jang-Liaw, and Hsiao-Wei Kao (2009) Molecular phylogeny and genetic differentiation of the Tanakia himantegus complex (Teleostei: Cyprinidae) in Taiwan and China. Zoological Studies 48(6): 823-834. Tanakia himantegus himantegus is a subspecies endemic to Taiwan (referred as the Taiwanese himantegus), while T himantegus chii is distributed in both Taiwan (referred as the Taiwanese chh) and China (referred as the Chinese chii). We analyzed the complete cytochrome (Cyt) b DNA sequences of 61 specimens of the T himantegus complex (including the Taiwanese chii, Chinese chii, and Taiwanese himantegus) to infer their phylogeny, genetic differentiation, and historical demography. Both Bayesian and maximum-likelihood trees showed that the Taiwanese chii, Chinese chii, and Taiwanese himantegus are 3 monophyletic groups. Among them, the Taiwanese chii clustered with the Chinese chii. The average pairwise genetic distance (HKY + G) between the Taiwanese chii and Chinese chii was 6.8%, which is smaller than 10.8% (distance between the Taiwanese chii and Taiwanese himantegus) and 11.8% (distance between the Chinese chii and Taiwanese himantegus). The results suggest that the Taiwanese chii is phylogenetically closer to the Chinese chii than to the Taiwanese himantegus. Sequence analyses showed that the Taiwanese chii has smaller genetic diversity (h = 0.771, pi = 0.0014) than the Chinese chii (h = 0.927, pi = 0.0087) and Taiwanese himantegus (h = 0.879, pi = 0.0066). The AMOVA revealed that about 92.8% of the genetic variance among sequences can be explained by differences among the 3 monophyletic groups (Taiwanese chii, Chinese chii, and Taiwanese himantegus). A unimodal mismatch distribution with a positively skewed distribution for the Taiwanese chii suggests that it has recently experienced sudden population expansions. Bimodal or ragged mismatch distributions for the Chinese chii and Taiwanese himantegus suggest that they are either admixtures of 2 expanding populations or stable populations. The origin of the Taiwanese chii is discussed based on the geographical history of Taiwan, records of fish collection, and phylogenetic analyses. http://zoolstud.sinica.edu.tw/JournaIs/48.6/823.pd