Data from: Phylogeny of salmonids (salmoniformes: Salmonidae) and its molecular dating: analysis of mtDNA data

Phylogenetic relationships among 41 species of salmonid fish and some aspects of their diversification-time history were studied using the GenBank and original mtDNA data. The position of the root of the Salmonidae phylogenetic tree was uncertain. Among the possible variants, the most reasonable seems to be that in which thymallins are grouped into the same clade as coregonins and the lineage of salmonins occupied a basal position relative to this clade. The genera of Salmoninae formed two distinct clades, i.e., (Brachymystax, Hucho) and (Salmo, Parahucho, (Salvelinus, (Parasalmo, Oncorhynchus)). Furthermore, the genera Parasalmo and Oncorhynchus were reciprocally monophyletic. The congruence of Salmonidae phylogenetic trees obtained using different types of phylogenetic markers is discussed. According to Bayesian dating, ancestral lineages of salmonids and their sister esocoids diverged about 106 million years ago. Sometime after, probably 100–70 million years ago, the salmonid-specific whole genome duplication took place. The divergence of salmonid lineages on the genus level occurred much later, within the time interval of 42–20 million years ago. The main wave of the diversification of salmonids at the species level occurred during the last 12 million years. The possible effect of genome duplication on the Salmonidae diversification pattern is discussed.本研究利用基因数据库（GenBank）及自主获取的线粒体DNA（mtDNA）数据，对41种鲑科鱼类的系统发育关系及其部分演化分化时间史展开了探究。鲑科系统发育树的根节点位置尚存不确定性。在多种可能的拓扑结构中，最合理的假说为：茴鱼亚科类群与白鲑亚科类群聚为同一演化支，而鲑亚科支系则位于该演化支的基部位置。鲑亚科各属形成两个独立演化支，即（短颌鲑属（Brachymystax）、哲罗鲑属（Hucho））与（鲑属（Salmo）、副哲罗鲑属（Parahucho）、（红点鲑属（Salvelinus）、（副大麻哈鱼属（Parasalmo）、大麻哈鱼属（Oncorhynchus））））。此外，副大麻哈鱼属与大麻哈鱼属互为单系群。本研究还探讨了采用不同类型系统发育标记所构建的鲑科系统发育树之间的一致性。基于贝叶斯定年结果，鲑科的祖先支系与其姊妹类群狗鱼科鱼类的分化时间约为1.06亿年前。在此之后的约1亿至7000万年前，发生了鲑科特有的全基因组复制事件。鲑科各属级支系的分化时间则晚得多，发生在4200万至2000万年前的区间内。而鲑科物种级的主要分化浪潮则集中于过去1200万年。本研究同时讨论了全基因组复制事件对鲑科分化模式的潜在影响。