The downstream section of the Jinsha River is a global biodiversity hotspot for fishes. However, cascade hydropower development has altered the original habitat and has had a huge impact on the area’s fish diversity. To assess the power of DNA barcoding and construct a DNA barcode library for Xiangjiaba reservoir area, 333 fish mitochondrial DNA barcodes (672 bp) employing a fragment of the mitochondrial cytochrome c oxidase subunit I gene (COI) were obtained for 57 species from the Xiangjiaba reservoir area in this study. The intra-specific genetic distances were below 2%, ranging from 0 to 1.69% (mean 0.19%). The interspecific genetic distances within genera ranged from 0.45 to 11.14% (mean 2.98%). The Bayesian inference (BI) tree and neighbor-joining (NJ) tree inferred that all species were unambiguously separated, with strong support values at the terminal branches except the node of Hemibarbus maculatus shared with its adjacent clade. The DNA barcoding gaps could accomplish fish species discrimination. These results revealed that DNA barcoding was an effective tool for the identification of fish species, and that it was possible to construct a robust DNA barcode reference library for fish species in the Xiangjiaba reservoir area. The results will contribute to future efforts in monitoring, conservation, and management of fish resources.

金沙江下游是全球鱼类生物多样性热点。但是，梯级水电开发改变了原始栖息地，并对该地区的鱼类多样性产生了巨大影响。为了评估DNA条形码的功能并为香家坝库区构建DNA条形码文库，使用了线粒体细胞色素c的片段的333条鱼线粒体DNA条形码（672 bp）本研究从香家坝库区获得了57个物种的氧化酶亚基I基因（COI）。种内遗传距离小于2％，范围为0至1.69％（平均0.19％）。属内种间遗传距离范围为0.45至11.14％（平均2.98％）。贝叶斯推理（BI）树和邻居联接（NJ）树推断所有物种都是明确分离的，在除Hemibarbus maculatus节点之外的末端分支上具有强大的支持值与附近的分支共享。DNA条形码的缺口可以完成鱼类的区分。这些结果表明，DNA条码是一种识别鱼类的有效工具，并且有可能在向家坝水库区建立一个健壮的DNA条码参考文库。结果将有助于今后在鱼类资源的监测，保护和管理方面的努力。