三种胡子鲶形态特征的统计分析及其分类意义

SYSTEMATIC VALUE AND STATISTICAL ANALYSIS OF MORPHOLOGICAL CHARACTERS IN THREE Clarias SPECIES

本文对胡子鲶Clarias fuscus、两栖胡子鲶Clarias batrachus及革胡子鲶Clarias lazera共125尾样品的10项形态测量性状及5项可数性状进行比较研究,并应用主分量分析和判别分析探讨种(或群体)间的分类关系。多变量统计分析结果:三种胡子鲶种间具有明显的间断,正判率均为100％;而胡子鲶的两个群体间的正判率为93.5％,并且没有明显的间断。研究结果与生化分析结果基本一致,表明中国存在两栖胡子鲶,三种胡子鲶是三个独立的种,区分三者的最有效特征为鳃耙数。我们认为,主分量分析和判别分析对鉴别外形非常相似的种类(如胡子鲶和两栖胡子鲶)有实用价值。

Data on 10 measural and 5 meristic characters in 5 samples of Clarias were compared for a total of 125 individuals, and the systematic relationships among species or populations were analysed using principal component analysis and discriminant function analysis. Multivariate statistics between species resulted in a 100% correct classification with apparent morphological gaps, and between two population of C. fuscus was 93.5% good classification with no gaps. Multivariate comparisions of body form among species, supported by biochemical results, indicate that 5 samples of Clorias can be grouped into three species, namely, C.fuscus, C.batrachus and C.lazera, and the first two can be found in China. The best character for classifying the three species was gill raker. It is considered that discriminant function analysis and principal component analysis can be used to classify the morphologically close related species such as C.fuscus and C. batrachus.