Morphological Variations Analysis of Different Geographic Populations of Procambarus clarkii

Morphological data of four different wild geographic populations of Procambarus clarkii collected from Jiangsu,Anhui,Shandong and Hubei provinces in China were analyzed.Thirteen proportion of morphometric trait were measured from crayfish and the degree of morphological variation among populations was calculated using three multivariate analyses.The results of cluster analysis showed that the morphometric characters of the Jiangsu population were more similar to those of the populations of Shandong than to those of the populations of Hubei and Anhui.In the principal component analysis of the female populations, three principal components were constructed, the contributory ratio of the first principal component was 46.104%,the second and the third was 25.375% and 10.830% respectively, the cumulative contributory ratio was 82.309%. Accordingly, for the male populations, three principal components were also constructed,their contributory ratios were 50.611%, 26.365% and 8.623%,respectively,the cumulative contributory ratio was 85.599%. Discriminant analysis indicated that the identification accuracy of female was 70.6%-100.0% (P1) and 52.9%-100.0% (P2). The total discriminant accuracy was 87.6%. The identification accuracy of male was 66.7%-100.0% (P1) and 66.7%-100.0% (P2);the total discriminant accuracy was 92.1%. All results supported that there are a little differences among P. clarkii populations on morphological characters; the morphological variations in different populations were mostly exhibited by carapace and abdominal. However, these morphological variations have not reached the level of subspecies.