Species identification is becoming a difficult task when there is a very little difference among them. In crustaceans things are more complicated as because they are quiet similar in appearance. To identify and differentiate between two sympatric freshwater prawn Macrobrachium lamarrei and M. lanchesteri in the northwestern Bangladesh collection of experimental samples were done from three different rivers from three different districts. Morphometric and meristic characters were applied for species recognition and statistical analyses were conducted to differentiate the prawn species. ANOVA (One way analysis of variance) was conducted at 5% level of significance to compare the values of 22 morphometric and4 meristic characters. The ANOVA showed the difference significantly at p>0.001, 0.01 and 0.05 in 15 morphometric and 3 meristic characters. To understand variation PCA (Principal Component analysis) and DFA (Discriminant Function Analysis) were tested. PCA products produced three components describing 71.77% variation due to 15 of 22 morphometric characters. The discriminate scores separated and correctly classified the two species. Hierarchical cluster analysis also distinguished the two species into two separate clusters. However, reliable molecular study needed for more authentications to differentiate species due to morphological plasticity. This study, by differentiating and correctly identifying of these species, will be helpful to conduct research in future.













