Discrimination of three closely related Aedes vectors using integrated morphological, morphometric and molecular approaches

Background Accurate identification of Aedes mosquitoes is essential for effective surveillance of arboviral diseases. Due to morphological similarities and vectorial potential of Aedes vittatus (Bigot), an important bridge vector of several arboviruses, i.e., dengue, chikungunya and Zika, was initially classified with Aedes aegypti (Linn.) and Aedes albopictus (Skuse). This study applied an integrative taxonomic approach to compare Ae. aegypti , Ae. albopictus and Ae. vittatus using a combination of visual morphological diagnostics, quantitative morphometric measurements and mitochondrial cytochrome c oxidase subunit I (COI) gene sequencing. Comparative analyses included cluster analysis of phenotypic traits and phylogeny based on COI sequences. Results Morphologically, 61% of the 31 adult attributes in Ae. vittatus differed from both Ae. aegypti and Ae. albopictus . Morphometrics of Ae. vittatus on banding patterns of the abdomen, tarsi, and palpi showed 28 distinct attributes out of 51 total attributes from both Aedes species ( P < 0.05). Cluster analyses based on both morphological and morphometric datasets consistently grouped Ae. aegypti and Ae. albopictus together, while Ae. vittatus formed a distinct cluster. Molecular phylogenetic analysis of COI sequences corroborated these findings, with Ae. vittatus forming a well-supported monophyletic clade clearly separated from the other two vectors. Genetic distance estimates further confirmed low intraspecific divergence and pronounced interspecific differentiation. Conclusion The strong concordance between phenotypic and genotypic attributes provides a robust and reliable framework for discriminating morphologically similar Aedes vectors. These datasets may help assess ecological variations and evolutionary patterns in these species.