白甲鱼属（鲤形目：鲤科）分子系统发育分析与分类整理

The cyprinid genus Onychostoma s.l. includes a group of rheophilic and benthic fish distributed in China and Southeast Asia. Due to high species diversity, it is a suitable candidate group for studies on regional biogeogrpahy and adaptation; some species are local food fish of economic importance. It is demonstrated that the current traditional taxonomy of the genus still remains uncertain over species delineation, generic definition and subdivison, and phylogenetic placement within the Cyprinidae. The aims of this proposed project are to assess the phylogenetic relationships of Onychostoma s.l. by integrating mtDNA and nuclear genes and based on sampling of more species, test the monophyly of the genus and then propose generic re-classification and scrutinize the taxonomic status of some currently recognized species of the genus, in combination with morphological data. The integrative method utilzed in this project is supposed to deepen our understanding of species diversity of the target group and can provide significant reference to taxonomic studies of rheophilic fishes; recognition of cryptic species is crucial for their bioconservation and utilization, particularly for economically exploited species, because some hidden taxa might actually be endangered as they are merged with more abundant species.

白甲鱼属是一类流水性底栖鱼类，分布于东南亚和中国。其物种多样性甚高，是区域生物地理学和适应性研究的理想类群, 有些种类具有重要的渔业价值。已有的研究发现，其传统分类存在诸多问题，如物种界定、属级概念及属下归类乃至于鲤科中系统位置等。本项目拟利用线粒体和核基因序列，构建该属物种的系统发育关系；依此检验其单系性，确立其属级概念，并整合形态特征，提出新的分类系统和评价目前所辨认物种的分类地位。此项目采用整合不同类型特征的研究方法，不仅可以深化对研究中类群多样性的认识，还可以为流水性鱼类类群的分类学研究提供借鉴；籍此研究, 识别隐含的物种对其多样性保护和利用至关重要，尤其是那些具经济价值的种类。

白甲鱼属是一类流水性底栖鱼类，分布于东南亚和中国。其物种多样性甚高，是区域生物地理学和适应性研究的理想类群, 有些种类具有重要的渔业价值。已有的研究发现，其传统分类存在诸多问题，如物种界定、属级概念及属下归类乃至于鲤科中系统位置等。本项目拟利用线粒体和核基因序列，构建该属物种的系统发育关系；依此检验其单系性，确立其属级概念，并整合形态特征，提出新的分类系统和评价目前所辨认物种的分类地位。研究结果显示，目前该属鱼类聚集于三个关系不密切的分支。据此重新界定了白鱼属，恢复了铲颌鱼属的有效性，并描述了两个新属。澄清了目前小口白甲鱼和粗须白甲鱼等目前分类上的混乱，并描述了两个新物种。该类学分类学编目和遗传多样性格局的识别为其多样性的保护与利用提供可靠的科学依据。本项目也为目前国内淡水鱼类物种分类研究提供新的思路。