Statistical Analysis of Indian Thaparocleidus (Monogenea: Dactylogyridae) Species based on Morphometric Characteristics

The present communication proposes statistical analysis of the morphometric data of haptoral parts of seventeen species belonging to genus Thaparocleidus Jain, 1952 described from different piscine hosts of India using principal component analysis (PCA), linear discriminant analysis (LDA) and multivariate analysis of variance (MANOVA). These statistical methods were applied to morphometric measurements made on anchors, transverse bars and marginal hooks for discrimination among the seventeen species. Initially, PCA showed the multivariate distinction between the seventeen species and able to differentiate the seventeen specimens into four groups. Thereafter, LDA confirmed the results of PCA and gave better classification. Both PCA and LDA showed that there are two morphometric parameters dorsal outer length (DOL) and ventral inner length (VIL) which fairly contributed to the discrimination between all seventeen species. This analysis of seventeen species indicated the presence of intra-specific morphometric variations and was subjected to more accurately distinguish their placement in respective genus. Findings are discussed in detail.