Nagl S, Tichy H, Mayer W E, Samonte I E, McAndrew B J, Klein J
Abteilung Immungenetik, Max-Planck-Institut für Biologie, Corrensstrasse 42, Tübingen, D-72076, Germany.
Mol Phylogenet Evol. 2001 Sep;20(3):361-74. doi: 10.1006/mpev.2001.0979.
African cichlid fishes are composed of two major lineages, the haplochromines and the tilapiines. Whereas the phylogenetic relationships of the haplochromines have been studied extensively, primarily because of their spectacular adaptive radiations in the Great Lakes of East Africa, little is known about the relationships among the tilapiine species, despite the fact that they have become an important component of African, indeed world, aquaculture. To remedy this situation, molecular phylogenetic analysis of tilapiine fishes was undertaken. A segment of mitochondrial DNA encompassing the terminal part of the tRNA(Pro) gene and the most variable part of the control region was amplified by the polymerase chain reaction with DNA samples isolated from 42 tilapiine species, and the amplification products were subjected to heteroduplex analysis and sequencing. Phylogenetic trees based on 68 sequences revealed the existence of 11 sequence groups and 11 single-sequence branches. The groups, designated Ti1 through Ti11, were distinguished by specific combinations of diagnostic substitutions, formation of monophyletic clusters, and separation by genetic distances in excess of 0.04. Although the relationships among the groups could not be resolved, the sequences separated Oreochromis and Sarotherodon from Tilapia, as defined by Trewavas. The Oreochromis sequences clustered with the Sarotherodon sequences and thus supported the hypothesis that the mouthbrooding behavior of the tilapiine fishes evolved only once from the substrate-spawning behavior. Since on phylogenetic trees the O. alcalicus (sub)species were always separated from O. amphimelas by other Oreochromis species, it was concluded that the adaptation to life in water with a high salt concentration and high pH values evolved independently at least twice in the tilapiine fishes. The tilapiines diverged from the haplochromines more than 8 million years ago; most of the intragroup divergences among the tilapiines took place an estimated 1.1 to 6 million years ago.
非洲丽鱼科鱼类由两个主要谱系组成，即帚齿非鲫谱系和罗非鱼谱系。帚齿非鲫谱系的系统发育关系已得到广泛研究，主要是因为它们在东非大湖中有惊人的适应性辐射，而关于罗非鱼谱系物种之间的关系却知之甚少，尽管它们已成为非洲乃至世界水产养殖的重要组成部分。为了纠正这种情况，对罗非鱼进行了分子系统发育分析。通过聚合酶链反应扩增了一段线粒体DNA，该片段包含tRNA(Pro)基因的末端部分和控制区最可变的部分，使用从42种罗非鱼物种中分离的DNA样本进行扩增，扩增产物进行异源双链分析和测序。基于68个序列构建的系统发育树显示存在11个序列组和11个单序列分支。这些组被命名为Ti1至Ti11，通过诊断性替换的特定组合、单系聚类的形成以及超过0.04的遗传距离分隔来区分。尽管各组之间的关系无法确定，但这些序列将奥利亚罗非鱼属和萨罗罗非鱼属与特鲁瓦瓦斯所定义的罗非鱼属区分开来。奥利亚罗非鱼属的序列与萨罗罗非鱼属的序列聚类，因此支持了罗非鱼科鱼类的口孵行为仅从底质产卵行为进化而来一次的假说。由于在系统发育树上，奥氏罗非鱼（亚）种总是被其他奥利亚罗非鱼属物种与暗色奥利亚罗非鱼分开，因此得出结论，罗非鱼科鱼类对高盐浓度和高pH值水体生活的适应至少独立进化了两次。罗非鱼谱系在800多万年前就与帚齿非鲫谱系分化；罗非鱼谱系内的大多数组内分化估计发生在110万至600万年前。
