鲂属鱼类形态差异分析

为探讨鲂属鱼类种内及种间形态差异,采用单因素方差分析及主成分分析对厚颌鲂(Megalobrama pellegrini)、广东鲂(M.hoffmanni)、鲂(M.skolkovii)和团头鲂(M.amblycephala)共382尾样本的23个可数性状和24个可量性状进行分析和比较。结果表明,4种鲂的可数性状(尾部脊椎数),可量比例性状(口宽/头长、眼径/头长、腹鳍棘长/头长、肠长/体长、尾柄高/体长、第一鳔室长/体长、第二鳔室长/第一鳔室长、尾柄长/尾柄高)存在显著性差异,可作为4种鲂的判别性状。通过主成分分析法对可数性状(可量比例性状)构建了3个主成分,其贡献率分别为:26.28%(26.01%)、19.92%(12.05%)和8.04%(10.18%),累计贡献率54.24%(48.24%)。主成分散点图显示,4种鲂聚为4簇,广东鲂、团头鲂区分明显。

Morphological variations among the genus Megalobrama

To investigate the difference among 4 species in genus Megalobrama,23 morphometric characters and 24 meristic characters were measured in 382 wild individuals of the genus Megalobrama by using one way anova and principal component analysis.The result showed that there were significant differences in the morphological characters(the number of caudal vertebrae) and meristic characters(mouth width/head length,eye diameter/head length,length of spine in ventral fin/ head length,intestines length/body length,caudal peduncle height/body length,the first swim bladder length/ body length,the second swim bladder length/ the first swim bladder length、caudal peduncle length/caudal peduncle height) among 4 species which can be used to distinguish the species among the genus Megalobrama.According to the principal component analysis of the morphometric characters(the meristic characters),three principal components were extracted and the related contribution ratios were26.28%(26.01%),19.92%(12.05%) and 8.04%(10.18%),respectively,with the cumulative contribution ratio of 54.24%(48.24%).Scatter plots of scores of principle components show ed that:four species of the genus Megalobrama formed 4 clusters,M.hoffmanni was clearly separated from M.amblycephala.