新疆克孜勒河4种裂腹鱼形态差异比较

Morphological Differences Among Four Schizothoracinae Species in the Kizil River Basin of Xinjiang

对新疆克孜勒河(Kizil River)流域4种裂腹鱼形态差异和生长特性进行比较分析,从形态特征上为群体的划分提供科学数据,为裂腹鱼的培育和种质资源保护提供理论依据。以2020年7月-2021年8月采自克孜勒河塔里木裂腹鱼(Schizothorax biddulphi)、宽口裂腹鱼(Schizothorax eurystomus)、厚唇裂腹鱼(Schizothorax irregularis)和斑重唇鱼(Diptychus maculates)共126尾个体为研究对象,通过传统形态测量学和基于地标点的几何形态测量学分析方法比较克孜勒河4种裂腹鱼的生长特性与形态差异。结果显示:4种裂腹鱼共有13个形态特征的平均值存在显著差异,且主要集中于头部、躯干部和尾部;利用tpsRegr软件的网格变形分析,4种裂腹鱼的形态差异主要体现在头部和尾部,其中斑重唇鱼鱼体较为纤细,头部偏小;通过主成分分析发现厚唇裂腹鱼、塔里木裂腹鱼和宽口裂腹鱼形态较为相近,而斑重唇鱼明显独立成一组群;聚类分析结果显示塔里木裂腹鱼群体和厚唇裂腹鱼群体首先聚为一支,再与宽口裂腹鱼聚为一支,最后与斑重唇鱼聚类。研究结果显示4种裂腹鱼群体存在形态差异,且与其地理分布密切相关。

The Kizil River in Xinjiang Province is an important feeding,breeding,and overwintering site for fish due to abundant resources.In recent years,various water conservancy projects constructed in the Kizil River Basin have had far reaching impacts on the integrity and biodiversity of aquatic ecosystems,resulting in a significant decline in wild populations of Schizothoracinae species.Differences in the external morphology and structure of fish are direct manifestations of adaptation to differing environmental conditions.In this study,we investigated the growth and morphological differences of four Schizothoracinae species(Schizothorax biddulphi,Schizothorax eurystomus,Schizothorax irregularis,Diptychus macu⁃lates)in the Kizil River Basin.We aimed to provide scientific data for classifying Schizothoracinae groups based on morphology,and provide a theoretical basis for cultivating and protecting germplasm resources of Schizothoracinae.Schizothoracinae specimens were collected from different river sections of Kizil River from July 2020 to August 2021,and a total of 126 individuals were obtained.Morphological measurements and species identification of all specimens were conducted,and morphological differences and growth characteristics of the four populations were analyzed using multivariate morphometric analysis and landmark-based analysis.There were significant differences in the mean values of 13 morphological metrics among the four Schizothoracinae species,and these differences were in the head,trunk,and tail.Grid deformation analysis using tpsRegr software showed that the morphological differences among the four species were primarily in the head and tail,consistent with the results obtained with traditional morphometric analysis,such as the more slender body and smaller head of D.maculates.Principal component analysis showed that the morphological characteristics of S.biddulphi,S.eurystomus and S.irregula⁃ris were similar,with Schizothoracinae in a separate group.Cluster analysis showed that S.biddulphi and S.irregularis first clustered into a group that then clustered with S.eurystomus,and finally clustered with D.maculates.In conclusion,the four Schizothoracinae groups in Kizil River have obvious morphological differences closely related to their geographical distribution.