In order to reduce the number of variables supporting the species distinction and to discard any potential effect of size among the 3 taxa (a clean-up process), all matrices were depurated by eliminating those variables found to be highly correlated or with little information. The former are simple redundant, while the latter represent variation which is very poorly explained through the PCA. As outcomes, a thirteen vari-able matrix was obtained for males and another with fourteen for females (Tables 3 and 4).