LAUSR

Differences of meristics, morphometrics characters and length-weight relationship were used to estimate the variability of wild and cultivated populations of the eastern river prawn, M. nipponense in the populations in Iranian Basin of the Caspian Sea. Three samples were collected from the northern and southern parts of the Caspian Sea in Iran. Ten measurements which made for each individual were size-standardized by allometric methods and principal component, and the resulting measurements were analyzed by cluster analysis and discriminant analysis (DA). The results of cluster analysis and DA indicated that the samples were clustered into two groups: the first group included the Caspian Sea sample; the second included the Anzali Lagoon and the third was Aquaculture farm sample. DA tests showed that morphometric, meristic and length-weight relationship differences among the two groups were significant. At least two morphologically populations of this species in the Iranian Basin of the Caspian Sea were determined. This study also suggested that external morphological traits in M. nipponense are variable and change markedly when exposed to different environmental conditions regardless of their geographic origin and that extensive variation was present among the populations studied.