Otwoma Levy M, Diemel Valeska, Reuter Hauke, Kochzius Marc, Meyer Achim
Leibniz Centre for Tropical Marine Research (ZMT), Bremen, Germany.
Kenya Marine and Fisheries Research Institute (KMFRI), Mombasa, Kenya.
J Fish Biol. 2018 Oct;93(4):597-608. doi: 10.1111/jfb.13686.
This study investigates the genetic population structure and connectivity of Acanthurus triostegus in five Indo-Pacific biogeographic regions (western and eastern Indian Ocean, western, central and eastern Pacific Ocean), using a mitochondrial DNA marker spanning the ATPase8 and ATPase6 gene regions. In order to assess the phylogeography and genetic population structure of A. triostegus across its range, 35 individuals were sampled from five localities in the western Indian Ocean and complemented with 227 sequences from two previous studies. Results from the overall analysis of molecular variance (AMOVA) without a priori grouping showed evidence of significant differentiation in the Indo-Pacific, with 25 (8.3%) out of 300 pairwise Φ comparisons being significant. However, the hierarchical AMOVA grouping of Indian and Pacific Ocean populations failed to support the vicariance hypothesis, showing a lack of a genetic break between the two ocean basins. Instead, the correlation between pairwise Φ values and geographic distance showed that dispersal of A. triostegus in the Indo-Pacific Ocean follows an isolation-by-distance model. Three haplogroups could be deduced from the haplotype network and phylogenetic tree, with haplogroup 1 and 2 dominating the Indian and the Pacific Ocean, respectively, while haplogroup 3 exclusively occurring in the Hawaiian Archipelago of the central Pacific Ocean.
本研究利用跨越ATPase8和ATPase6基因区域的线粒体DNA标记，调查了印度-太平洋地区五个生物地理区域（印度洋西部和东部、太平洋西部、中部和东部）的三刺刺尾鱼的遗传种群结构和连通性。为了评估三刺刺尾鱼在其分布范围内的系统地理学和遗传种群结构，从印度洋西部的五个地点采集了35个个体，并补充了之前两项研究中的227个序列。在没有先验分组的情况下，分子方差分析（AMOVA）的总体结果显示，印度-太平洋地区存在显著分化的证据，在300个成对Φ比较中，有25个（8.3%）具有显著性。然而，对印度洋和太平洋种群进行的分层AMOVA分组未能支持隔离分化假说，表明两个大洋盆地之间不存在遗传间断。相反，成对Φ值与地理距离之间的相关性表明，三刺刺尾鱼在印度-太平洋地区的扩散遵循距离隔离模型。从单倍型网络和系统发育树中可以推断出三个单倍群，单倍群1和2分别在印度洋和太平洋占主导地位，而单倍群3仅出现在太平洋中部的夏威夷群岛。
