Padrões sazonais de drosofilídeos (Insecta, Diptera) nativos e exóticos da Caatinga

Abstract

Despite its large extension and number of endemic species, the Caatinga is still a neglected biome in terms of the production of scientific knowledge. Until then, only a few studies were concerned with analyzing the seasonal distribution of native and exotic invasive species in the northeast region of Brazil, especially in the Caatinga. This study aimed to evaluate the influence of seasonality on the abundance of native and exotic Caatinga drosophilids. A literature review was carried out, consulting the SciELO, Scopus, Science Direct, Google Scholar and PubMed databases. Using the search terms "Caatinga", "Drosophilidae", "Seasonality", "Seasonality", "Exotic species", "Drosophila", "Rain", "Dry", "Rainfall", "Dry", "Neotropical" and “Invasive species”, we selected five studies carried out between 2010 and 2017 that investigated the seasonality of drosophilids in the Caatinga. The results of these studies were analyzed, and the chi-squared test of adherence was performed to assess the differences between the abundances. Three exotic species and six native species were analyzed, totaling 21,428 individuals. Both native and exotic species showed preference for rain, noting that 84.5% of the total individuals were sampled in this period. The most abundant species was Drosophila willistoni, which corresponded to 36.4% of the total number of individuals collected in both periods. All species were more abundant in the rainy season individually, with the exception of the native Drosophila cardini. The seasonal patterns observed are similar to those of other groups of organisms in Caatinga, such as birds and amphibians, which also have a preference for rain. The seasonality of native species of drosophilids follows patterns observed in other biomes in Brazil and the world, where the preference is for rain. The seasonality of exotic species differs from that observed in some places, probably due to the low number of samplings carried out with exotic species. The results obtained reinforce the need to further investigate the seasonality of exotic drosophilids in the Caatinga, in order to obtain more reliable results about the biology of these species and prevent future biological invasions in the biome.