In order to understand the morphological differences between four populations
of genus Coilia (Teleostei: Clupeiforms) and identify them conveniently, truss
network data were used to conduct multivariate analysis. Nineteen morphometric
measurements were made for each individual. Burnaby's multivariate method
was used to obtain size-adjusted shape data. The cluster analysis and
discriminant analysis were used to discriminate among populations. The
results indicated that 1) the four populations were clustered into three
distinct groups; the first group included Changjiang C. mystus and Taihu C. ectenes, the second one included Zhujiang C. mystus, the last one included Changjiang C. ectenes, and 2)
discriminant analysis with selected 4 morphological parameters showed that
the identification accuracy was between 88% and 100%, and global
identification accuracy was 95%. Our result showed that populations of
different Coilia species living in geographic proximity to one another are more
similar than conspecifics living farther apart. Separation and adaption are
important to morphological difference. The taxonomy of genus Coilia should be
reconsidered. This study also showed that the method to obtain size-adjusted
data is important to acquire right conclusion.