Data from: Phylogenetic and morphological diversity of the Etheostoma zonistium species complex with the description of a new species endemic to the Cumberland Plateau of Alabama

We provide a description of the Blueface Darter, Etheostoma cyanoprosopum, which is distributed in the upper Sipsey Fork of the Mobile Basin and the upper portion of the Bear Creek system in the Tennessee River Drainage. The distinctiveness of Etheostoma cyanoprosopum is assessed through analysis of morphological variation and molecular phylogenetic diversity within the Etheostoma zonistium species complex. In addition to analyzing disparity of morphometric and meristic traits, we present phylogenetic analyses of a mitochondrial gene and two nuclear genes and identify genetic clusters through analysis of 25 microsatellite loci. In the mitochondrial DNA (mtDNA) gene tree, Etheostoma cyanoprosopumis resolved as the sister lineage to a clade containing all other species of the Etheostoma zonistium complex. Etheostoma zonistium is paraphyletic with respect to both Etheostoma pyrrhogaster and Etheostoma cervus, which do not resolve as sister species in the mtDNA gene tree. The two nuclear gene trees are much less resolved, but the S7 ribosomal protein intron 1 (S7) gene tree resolves Etheostoma cyanoprosopum and all sampled populations of Etheostoma zonistium as a clade with strong Bayesian posterior node support. Etheostoma cyanoprosopum is morphologically differentiated from Etheostoma zonistium by a shallower body, a more elongate nape, a higher number of lateral line scales, a higher number of transverse scale rows, and differences in coloration.本研究对蓝脸镖鲈（Blueface Darter，*Etheostoma cyanoprosopum*）进行了系统描述，该物种分布于莫比尔盆地（Mobile Basin）的西普西叉河上游，以及田纳西河流域（Tennessee River Drainage）内的贝尔溪水系上游河段。本研究通过分析带纹镖鲈物种复合群（*Etheostoma zonistium* species complex）内的形态变异与分子系统发育多样性，评估了蓝脸镖鲈的分类独特性。除分析形态测量性状与计数性状的差异外，本研究还对1个线粒体基因与2个核基因开展了系统发育分析，并通过25个微卫星位点（microsatellite loci）的分型鉴定了遗传聚类群。在线粒体DNA（mtDNA）基因树中，蓝脸镖鲈被解析为包含带纹镖鲈物种复合群其余所有物种的演化支的姊妹支系。带纹镖鲈与红腹镖鲈（*Etheostoma pyrrhogaster*）、颈背镖鲈（*Etheostoma cervus*）均呈并系群关系，且在线粒体基因树中，后两者并未被解析为姊妹物种。两个核基因的系统发育树分辨率普遍较低，但S7核糖体蛋白内含子1（S7 ribosomal protein intron 1，简称S7）基因树将蓝脸镖鲈与所有采样的带纹镖鲈种群解析为一个单系演化支，且该分支具有较高的贝叶斯后验节点支持率。蓝脸镖鲈在形态上与带纹镖鲈存在明确区分：其体高较低、颈背区域更修长、侧线鳞数量更多、横列鳞行数更多，且体色存在显著差异。