新疆叶尔羌河流域4种裂腹鱼多变量形态学对比分析

Comparative analysis of multivariate morphology of four species of Schizothoracinae in the Yarkand River basin of Xinjiang

为明确叶尔羌河流域4种裂腹鱼的表型差异,实验整合传统形态学和框架分析法2个数据体系,利用多变量形态学统计分析法对叶尔羌河流域裂腹鱼类(4种,494尾,48组参数)开展分析。单因子方差分析结果显示,9个参数同时在4种裂腹鱼中存在显著差异,差异主要位于头部、前躯干部和后躯干部;主成分分析结果显示,重唇裂腹鱼与厚唇裂腹鱼形态数据在PC1轴上差异显著,主要反映头部特征;而框架数据结果显示,塔里木裂腹鱼和宽口裂腹鱼在第一主成分上差异较大,主要体现在后躯干部;2个数据体系逐步判别分析分别选取8个和6个主要参数建立判别公式,初始判别成功率分别为85.7%和75.7%,散点图组质心分离,样品重叠少;聚类分析结果显示,2个数据体系均分为2个分支,其中重唇裂腹鱼单独成一支,塔里木裂腹鱼与厚唇裂腹鱼在形态上距离较近,与宽口裂腹鱼次之。研究表明,2个数据体系中,形态数据表现较优于框架数据;叶尔羌河流域4种裂腹鱼外部形态存在显著差异,利用多元统计方法可以较好区分,但仍存在一定的重叠。

The Yarkand River is located on the western edge of the Tarim Basin in southwestern Xinjiang,and the longest source of the Tarim River.Affected by the uplift of the Qinghai-Tibet Plateau at the end of the Tertiary Period,this waters gradually formed a unique fish population structure,with Schizothoracinae as its typical representative species.Typical representatives of Schizothoracinae included Schizothorax irregularis,S.eurystomus,S.biddulphi and S.barbatus.The four common Schizothoracinae are highly similar in appearance,and the countable and measurable traits are mostly crossed.Affected by work experience and cognition,the four species are prone to misjudgment in the identification,and many scholars often question this classification system.This paper intends to establish a discrimination system for Schizothoracinae identification through comparing traditional morphometric and Box-truss data system,and provide reference and information for subsequent research.The differences among the species of Schizothoracinae(4 species,494 individuals,48 groups of parameters)were detected through ANOVA,PCA,DFA and Cluster Analysis.The results of ANOVA showed that 9 parameters were significantly different in the 4 species of Schizothoracinae at the same time(P<0.05),and the difference was mainly located in the head,front trunk and rear trunk of the fish.PCA results showed that there was significant difference in PC1 axis between S.barbatus and S.irregularis based on the morphological data,which is mainly represented the head characteristics.However,the results of the Box-truss data showed that the difference between S.biddulphi and S.eurystomus mainly reflected in the rear trunk.The 8 and 6 main parameters were selected to establish the discriminant formulas for two data structures,and the initial discrimination success rates reached 85.7% and 75.7%,respectively.The cluster analysis results showed that the two data systems are divided into two branches,among which S.barbatus is a separate group,the S.biddulphi and S.irregularis are closer in morphology,followed by S.eurystomus.The using of multivariate statistical methods can better distinguish the four Schizothoracinae species in the Yarkand River Basin,and the morphological data performed better than the Box-truss data by contrasting two data systems.However,there is still confused distinguish characteristic in species identification.These findings can be used to quickly verify the Schizothoracinae that are difficult to accurately identify based on the lip characteristics,and would accumulate basic data to provide a reference for follow-up research.