Variação na morfologia alar de Drosophila nasuta (Diptera, Rosophilidae) em biomas invadidos na América do Sul

Abstract

Invasive species are one of the biggest drivers of biodiversity loss on the planet. It is believed that invasions will continue to increase around the world. A recent example of invasion in South America is the arrival of the fly Drosophila nasuta Lamb 1914. After about a decade of invasion, the species already occupies 4.6 million km² in Brazil, around 55% of the country. D. nasuta presents an ecological pattern different from other exotic drosophilids, preferring conserved locations, being possibly responsible for reductions in the abundance of native dro- sophilids after its invasion. Genetic analyses show population differentiation of D. nasuta in the collected areas. The morphology of drosophilids can be modified through several factors, biotic and abiotic. Wings have advantages in morphology studies, as they are resistant and 2D structures, and have already been used extensively in studies with drosophilids. The objective of the work was to observe whether D. nasuta already presents differentiation in wing mor- phology in the areas. 240 right wings of males of D. nasuta, found in eight locations. Each wing was photographed and digitized, and 11 measurements were subsequently taken from reference points. Analysis of Variance (ANOVA) and an a posteriori Tukey test were perfor med to observe whether the areas differed in a statistically significant way. Areas that did not differ significantly were subsequently grouped and a linear discriminant analysis was perfor- med. Furthermore, a Pearson Correlation test was performed with abiotic factors: minimum and maximum temperature, and rainfall. The analyzes formed two groups, one with the largest (Caatinga, Cerrado and South Atlantic Forest) and the other with the smallest (Amazonia and North Atlantic Forest). It is believed that a bigger wing allows better survivability in cold en- vironments. The results demonstrated that D. nasuta presents differences in wing morphology in the different locations found, showing that the species is well adapted to Brazilian biomes.