In the last three decades some faunal surveys of Drosophilidae have been done in several environments in the Neotropical region, especially in Brazil. But approximately 30 to 50% of the drosophilids in Brazil have not yet been described, and the degradation of some biomes causes a profound loss of species diversity, as well as the loss of information about the present structureof their communities. This is the situation with the pampas biome, which covers southernmost Brazil, all of Uruguay, and the central region of eastern Argentina. For the present study, seasonal collections were made in a natural area of pampas within the limits of the municipality of Bossoroca in the state of Rio Grande do Sul, Brazil (28°45’01”S 54°56’55”W), from April 2011 to April 2012. A total of 7,164 drosophilids of 51 species were collected, comprising 36 species belonging to Drosophila Fallén, ten of Rhinoleucophenga Hendel, two of Amiota Loew, two of Zygothrica Wiedemann and one of Zaprionus Coquillett. Some species were recorded for the first time in pampas: Drosophila briegeri Pavan & Breuer, D. fuscolineata Duda, Rhinoleucophenga obesa (Loew), R. punctulata Duda, R. subradiata Duda and Zygothrica orbitalis (Sturtevant). Furthermore, three new species of genus Rhinoleucophenga were described: R. pampeana sp. nov., R. missionera sp. nov. and R. sulina sp. nov. A dichotomous key is given for the Rhinoleucophenga species recorded in pampas. An intensive literature search is reviewed of drosophilid species recorded in pampas of Brazil, Uruguay and Argentina, including taxonomic, genetic, evolutionary, and ecological studies. Despite Brazilian pampas being the richest when compared with Uruguay and Argentina, the three countries presented the same problem: huge areas with a barely surveyed Drosophilidae fauna. The combination of this information and the knowledge of the current state of preservation of pampas stress the necessity and importance of creating new conservation areas to preserve the natural biodiversity of pampas.

The New World genus Rhinoleucophenga (Diptera: Drosophilidae): new species and notes on occurrence records

The Pampas biome is a subtropical–temperate grassland region that presents striking climatic characteristics, such as temperatures below zero in the winters and up to 40°C in the summers. Hence, long sampling periods are necessary to better understand the structure of Drosophilidae assemblages through current climatic conditions in the heterogeneous landscape of the Pampas. Samples of drosophilids were taken in natural and urban areas during 12 climatic periods. The environmental influence on the structure of assemblages was temporally and spatially analyzed through nonmetric multidimensional scaling, indicator value, and permutational multivariate analysis of variance. The following hypotheses were tested: 1) the structure of drosophilids assemblages vary through different habitats from the same area, and 2) the presence and abundance of Drosophilidae species in a particular environment is regulated by the interaction between the phytophysionomy and climatic traits of each locality. The Pampas assemblages were dominated by a few species, although it is a highly diverse biome with regards to Drosophilidae. The environmental heterogeneity was confirmed as a determinant factor of the structure of assemblages, and it explained 8.86% of the assemblage composition. Nonetheless, the interaction between temperature and humidity was revealed as the most influential environmental component of the Drosophilidae assemblages, and it explained 37.28% of all the recorded variation. Together, environment type and the climatic elements were able to explain 56.45% of the assemblages’ variation. Open and close environments, such as grassland and forest patches, respectively, presented a peculiar composition of Drosophilidae assemblages and should be equally considered in the Pampas preservation strategies. Resumo O bioma Pampa é uma região campestre subtropical–temperada que apresenta características climáticas marcantes, invernos com temperaturas negativas e verões com registros de mais de 40°C. Longos períodos de amostragem são necessários para o melhor entendimento da estrutura das assembleias de Drosophilidae na paisagem heterogênea do Pampa. Coletas de drosofilídeos foram realizadas em áreas naturais e urbanas do Pampa durante 12 períodos climáticos. A influência ambiental sobre a estrutura das assembleias foi temporal e espacialmente analisada por meio de nMDS, IndVal e PERMANOVA. As seguintes hipóteses foram testadas: 1) a estrutura das assembleias de drosofilídeos variam através de diferentes habitats de uma mesma área e, 2) a presença e a abundância das espécies de Drosophilidae em um ambiente são reguladas pela interação da fitofisionomia e características climáticas de cada local. As assembleias do Pampa foram dominadas por poucas espécies, embora este seja um bioma muito diverso com relação à fauna de Drosophilidae. A heterogeneidade ambiental foi um fator determinante na estrutura das assembleias, explicando 8,86% da composição das mesmas. No entanto, a interação entre temperatura e os níveis de umidade foi indicada como o componente ambiental mais influente sobre as assembleias de Drosophilidae, explicando 37,28% de toda a variação percebida. O tipo de ambiente amostrado e os componentes climáticos juntos explicaram 56,45% da variação nas assembleias. Ambientes abertos e fechados, campos e matas, respectivamente, apresentaram uma composição própria para as assembleias de Drosophilidae e, devem ser igualmente considerados em estratégias de preservação do Pampa.

The genus Rhinoleucophenga Hendel comprises 29 nominal species with New World distribution. In the present study five species are redescribed: R. angustifrons Malogolowkin; R. lopesi Malogolowkin; R. matogrossensis Malogolowkin; R. nigrescens Malogolowkin and Rhinoleucophenga personata Malogolowkin. R. capixabensis Culik & Ventura is proposed as a new junior synonymy of R. lopesi. Other species, R. jacareacanga sp. nov., is described from the specimens deposited at CEIOC/Fiocruz. The description of new species and review of some former descriptions of Rhinoleucophenga is indispensable since the distribution records of some species are doubtful.