Invasion and Spreading of Drosophila nasuta (Diptera, Drosophilidae) in the Caatinga Biome, Brazil

Biological invasions are one of the main causes of biodiversity loss, and it is essential to understand the pattern and rate of expansion of invasive species outside their native distribution. In this study, we documented the invasion of the Asian fruit fly, Drosophila nasuta Lamb, in the Caatinga, and measured its geographical distribution in this environment, which covers 11% of the Brazilian territory. We collected drosophilids in eight sites distributed in the north of the Caatinga (in the state of Ceara), in the south (in Bahia), in the east (in Pernambuco), and in the west (in Piaui), as well as in sites in the central area of the biome. Drosophila nasuta occurred in all areas and was one of the most frequently occurring species in half of the sampled sites. We observed greater abundance in areas with arboreal vegetation and a possible preference of this species for areas with higher annual rainfall in the Caatinga. Of all the biomes where D. nasuta is found in Brazil, the area occupied in the Caatinga is the largest documented to date. Our results show D. nasuta's success in invading the Caatinga and the vast area this species has colonized in this biome. The success of this invasion can be explained by the high fertility and short life cycle as well as by the ability of D. nasuta to use different trophic resources.

Automated summary

Biological invasions, such as the invasion of the Asian fruit fly into the Caatinga biome in Brazil, are a major cause of biodiversity loss globally. The success of Drosophila nasuta in colonizing this environment may be attributed to its preference for areas with arboreal vegetation and higher annual rainfall. The ability of this species to utilize different trophic resources also contributes to its successful invasion.