Resolution of cryptic mosquito species through wing morphometrics

Area of Science:

• Entomology
• Vector Biology
• Morphometrics

Background:

• Accurate mosquito species identification is vital for understanding vector biology and implementing effective control strategies.
• Morphologically similar species pose significant identification challenges, hindering vector control efforts.
• Wing morphometrics presents an underexplored yet promising method for rapid and precise mosquito classification.

Purpose of the Study:

• To evaluate the utility of wing morphometrics for differentiating cryptic mosquito species, specifically the Culex (Culex) vishnui group and Culex (Lophoceraomyia) subgenus.
• To explore population-level variations in wing shape within Aedes albopictus across different habitats.
• To validate morphometric identifications using the Cytochrome oxidase subunit I (COI) gene sequence.

Main Methods:

• Geometric morphometric analysis of 20 wing landmarks from 227 mosquito specimens.
• Procrustes ANOVA regression and Canonical Variate Analysis (CVA) to analyze wing shape variations.
• DNA sequencing of the COI gene for species identification validation.

Main Results:

• Wing shape analysis demonstrated significant differences among species, achieving >97% cross-validation accuracy for differentiating the two Culex groups.
• Wing morphometrics revealed population-level variations in Aedes albopictus wing shape, though with lower cross-validation accuracy.
• COI gene sequencing corroborated the morphological and morphometric findings.

Conclusions:

• Wing geomorphometric analysis is a robust and reliable tool for resolving cryptic mosquito species, including medically important vectors, occurring in sympatry.
• This method provides a valuable, non-destructive approach for mosquito identification in vector control and ecological studies.
• Further research may refine the application of wing morphometrics for population-level studies in other mosquito species.