Heckman K L, Near T J, Alonzo S H
Department of Ecology and Evolutionary Biology, Yale University, 165 Prospect Street, New Haven, CT 06511, USA.
Mol Phylogenet Evol. 2009 Oct;53(1):249-57. doi: 10.1016/j.ympev.2009.05.027. Epub 2009 May 31.
Darters represent a species rich group of North American freshwater fishes studied in the context of their diverse morphology, behavior, and geographic distribution. We report the first molecular phylogenetic analyses of the Boleosoma darter clade that includes complete species sampling. We estimated the relationship among the species of Boleosoma using DNA sequence data from a mitochondrial (cytochrome b) and a nuclear gene (S7 ribosomal protein intron 1). Our analyses discovered that the two Boleosoma species with large geographic distributions (E. nigrum and E. olmstedi) do not form reciprocally monophyletic groups in either gene trees. Etheostoma susanae and E. perlongum were phylogenetically nested in E. nigrum and E. olmstedi, respectively. While analysis of the nuclear gene resulted in a phylogeny where E. longimanum and E. podostemone were sister species, the mitochondrial gene tree did not support this relationship. Etheostoma vitreum was phylogenetically nested within Boleosoma in the mitochondrial DNA and nuclear gene trees. Our analyses suggest that current concepts of species diversity underestimate phylogenetic diversity in Boleosoma and that Boleosoma species likely provide another example of the growing number of discovered instances of mitochondrial genome transfer between darter species.
镖鲈是北美淡水鱼中一个物种丰富的类群，人们从其多样的形态、行为和地理分布的角度对其进行了研究。我们报告了对包括完整物种样本的博氏镖鲈分支进行的首次分子系统发育分析。我们利用来自线粒体（细胞色素b）和一个核基因（S7核糖体蛋白内含子1）的DNA序列数据，估计了博氏镖鲈各物种之间的关系。我们的分析发现，两个地理分布广泛的博氏镖鲈物种（黑斑镖鲈和奥尔姆斯特德镖鲈）在两个基因树中均未形成相互单系类群。苏珊镖鲈和长体镖鲈在系统发育上分别嵌套于黑斑镖鲈和奥尔姆斯特德镖鲈之中。虽然对核基因的分析得出了一个系统发育关系，即长鳍镖鲈和石生镖鲈是姐妹物种，但线粒体基因树并不支持这种关系。玻璃镖鲈在系统发育上在线粒体DNA和核基因树中嵌套于博氏镖鲈属内。我们的分析表明，当前的物种多样性概念低估了博氏镖鲈属的系统发育多样性，并且博氏镖鲈属物种可能为镖鲈物种间线粒体基因组转移这一越来越多被发现的实例提供了另一个例子。
