Pandey Ajay, Lakra Wazir S, Thapliyal Rajendra P, Goswami Mukunda, Singh Mahender, Malakar Abhishek K
Department of Zoology and Biotechnology, HNB Garhwal Central University , Srinagar, Garhwal, Uttarakhand, India.
Mitochondrial DNA. 2012 Jun;23(3):239-49. doi: 10.3109/19401736.2012.674117.
The fishes in this study belong to the difficult group. It is difficult to identify about more than 50 nemacheilid loach species in India, mainly due to the poor quality of the original descriptions, the lack of good reviews, and the similarity of a number of the banded species. In view of this, a morphometric and genetic study was conducted on four species that have been documented in Central Himalayan region of India. Using comparative methods, a contribution to the knowledge about the variability of four Himalayan hillstream loaches, a molted loach Acanthocobitis botia (Hamilton, 1822), Nemacheilus corica (Hamilton, 1822), a creek loach Schistura beavani (Gunther, 1868), and Schistura montana (McClelland, 1838), was accomplished. Morphometric data were analyzed by univariate (CV and analysis of variance) and multivariate analyses (discriminant function analysis and cluster analysis). Based on the results of these statistical analyses, generally all four species grouped into their own species cluster with minimal overlap between two species of genus Schistura. Mitochondrial DNA cytochrome b (Cyt b) gene analysis revealed 7.7-17.6% genetic distances among the four species. Molecular phylogenetic relationship among these species and other Balitoridae species was investigated using published mitochondrial Cyt b sequences. Dendrograms obtained by the maximum likelihood and maximum parsimony method analyses exhibited the same topology. According to this topology, all the four species represented distinct species group and A. botia form the most distinct species while S. beavani and S. montana are clustered together with Nemacheilus species to form a single group. This work may build the base for the revision of taxonomic identity of fishes of the family Balitoridae. The results may further help to enhance the knowledge of the ichthyologists in understanding the fish fauna of India and assist them in planning conservation and management strategies for the propagation of these less studied small indigenous species along their natural range of distribution.
本研究中的鱼类属于难鉴定类群。在印度，要鉴定50多种条鳅科泥鳅物种很困难，主要原因是原始描述质量差、缺乏完善的综述，以及许多带纹物种形态相似。鉴于此，对印度喜马拉雅中部地区已记录的4个物种进行了形态测量和遗传学研究。采用比较方法，对4种喜马拉雅山溪流泥鳅的变异性研究作出了贡献，这4种泥鳅分别是斑纹鳅Acanthocobitis botia（汉密尔顿，1822年）、科氏条鳅Nemacheilus corica（汉密尔顿，1822年）、溪流条鳅Schistura beavani（冈瑟，1868年）和山地条鳅Schistura montana（麦克莱兰，1838年）。形态测量数据通过单变量分析（变异系数和方差分析）和多变量分析（判别函数分析和聚类分析）进行分析。基于这些统计分析结果，一般来说，所有4个物种都聚为各自的物种簇，条鳅属的两个物种之间重叠最小。线粒体DNA细胞色素b（Cyt b）基因分析显示，这4个物种之间的遗传距离为7.7%-17.6%。利用已发表的线粒体Cyt b序列，研究了这些物种与其他平鳍鳅科物种之间的分子系统发育关系。通过最大似然法和最大简约法分析得到的系统发育树显示出相同的拓扑结构。根据这个拓扑结构，所有4个物种代表不同的物种组，斑纹鳅形成最独特的物种，而溪流条鳅和山地条鳅与条鳅属物种聚在一起形成一个单一组。这项工作可为平鳍鳅科鱼类分类身份的修订奠定基础。研究结果可能进一步有助于鱼类学家加深对印度鱼类区系的了解，并协助他们制定保护和管理策略，以便在这些较少研究的小型本土物种的自然分布范围内对其进行繁殖。
