Assessment of the microgeographic population structure of Aedes fluviatilis (Diptera: Culicidae) using wing geometric morphometrics

Abstract

Aedes fluviatilis (Lutz 1904) is a highly anthropophilic mosquito found in the New World from Argentina to Mexico. Environmental changes, such as those resulting from urbanization, may lead to population structure in mosquitoes. As exogenous factors may be acting on and influencing Ae. fluviatilis population dynamics, this study sought to assess population structure patterns in this species in the city of Sao Paulo, Brazil, with the aid of wing geometric morphometrics, a widely used and reliable tool for studying microevolution. Multivariate analysis revealed variation among wing shape of Ae. fluviatilis in the different urban parks. Our results indicated that both male and female populations studied here were distributed homogeneously in morpho space with signs of population structuring. The differences in the male and female Neighbor Joining phenograms based on wing shape variations indicate that there is a difference in population structure between male and female populations, with higher differentiation in males. The values of Mahalanobis Distances between populations of females and males were relatively high considering that the specimens analyzed have low variation in space and time (specimens were collected in locations no more than 20 km apart over one year period). Wing geometric morphometrics analysis of Ae. fluviatilis showed that populations of males and females have a distinct structuration, which reflected in the distinct wing shape variations found for each gender, in which males displayed greater wing shape variation than females.