Qualitative and Quantitative Characterization of Some Common Bivalves: Polymesoda bengalensis, Codakia tigerina and Anodontia edentula

For more than a hundred years the morphology of bivalves was an object of research. The best way to explore bivalve morphology is on the shell. The shell provides a wide array of variability and is important for the effective culture of these organisms. In this study, the right and left valve interiors of the three species belonging to the family Cyrenidae (Polymesoda bengalensis) and Lucinidae (Codakia tigerina and Anodontia edentula) were explored for phenotypic variations using Geometric Morphometrics (GM) tools coupled with Canonical Variance Analysis (CVA), Multivariate Analysis of Variance (MANOVA), Relative Warp Analysis (RWA), and Kruskal-Wallis test. Ten (10) anatomical landmark tests were performed -covering the visible morphological characteristics of the internal shell. The analyses showed that the formation of the hinge plate, distance of the pallial line, and the orientation of the muscle scar are significantly different. These features are usually affected by habits and habitats of the particular species. Hence, these characters are better suited for functional morphological analysis and should be incorporated when studying intrapopulation and interpopulation variation