Correlation of length of terminalia of males and females among nine species of Bactrocera (Diptera: Tephritidae) and differences among sympatric species of B. dorsalis complex

The lengths of the male aedeagus and the female aculeus were measured in 9 Bactrocera fruit fly species. A significant linear correlation was observed between the length of aedeagus and the length of the aculeus. It is noteworthy that B. papayae Drew & Hancock and B. philippinensis Drew & Hancock have extremely long aedeagi. Previously, differentiation between males in 2 sets of sympatric species, B. papayae versus B. carambolae Drew & Hancock, and B. philippinensis versus B. occipitalis (Bezzi), was extremely difficult. However, observed differences in the length of the aedeagus and aculeus now provides means to distinguish clearly between some sympatric species within the B. dorsalis complex, and identify accurately both males and females to species.