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Although drosophilids are widespread models in genetics and molecular biology, their diversity and distribution is relatively poorly known. Field information is important because it provides an appropriate framework to interpret genetic and evolutionary studies. We sampled drosophilids in the Brazilian savanna, one of 34 biodiversity hot spots worldwide. This extremely rich and endangered biome is highly seasonal and consists of a vegetation mosaic, ranging from open fields to riparian forests; these forests occupy only 5% of the Brazilian savanna but concentrate most of the biome s diversity. Twelve monthly collections in a riparian forest of the Brazilian savanna revealed 61 drosophilid species, comprising the genera Amiota Loew, Drosophila Fallén, Neotanygastrella Duda, Rhinoleucophenga Hendel, Scaptodrosophila Duda, Zaprionus Coquillett, and Zygothrica Wiedemann. This richness represents about a half of the recorded drosophilid species of the whole biome, and includes five new occurrences for the Brazilian savanna: the genus Amiota, Drosophila coffeata Williston, D. neorepleta Patterson and Wheeler, D. pseudosaltans Magalhães, and Rhinoleucophenga brasiliensis (Lima). This result suggests that drosophilid richness in this biome is likely to be high but remains understudied. [ABSTRACT FROM AUTHOR]

The authors discuss the results of their study on the characteristics of assemblages of drosophilids in three mangrove forests of Santa Catarina Island in southern Brazil. About 56% of 82,942 drosophilids were Drosophila (D.) simulans Sturtevant. D. mercatorum have lower abundances in Ratones than in Itacorubi. No significant differences were found between three mangroves in terms of species accumulation among rare and infrequent species and diversity. They conclude that the three mangrove forests are very similar due to lack of lack of statistical difference in absolute abundances among 16 of 17 most common species.

The Brazilian Cerrado, a vegetation mosaic considered to be a unique savannah hotspot, contains a great diversity of insects. It is uncertain how communities of insects in the Cerrado respond, at local scale, to the strong heterogeneity of the biome or to the increasing levels of anthropogenic disturbance., This study examines the relative importance of habitat heterogeneity and human disturbance for the structure of drosophilid assemblages in this biome., Our results are based on standardised monthly sampling at 25 sites (3 conserved forests, 4 disturbed forests, 8 conserved savannahs, and 10 disturbed savannahs) throughout 1 year., The assemblage compositions differed across habitats. The conserved forests had a singular drosophilid assemblage characterised by typical narrow-ranging neotropical species. Assemblages from savannahs and disturbed forests contained more exotic species than those from conserved forests. The assemblages of disturbed forests were more similar to those of the savannahs than to those of the conserved forests. Savannah assemblages did not differ from each other; these assemblages shared a great number of both exotic and neotropical species widespread in neotropical regions., At the reserve scale, the strong natural heterogeneity of the Cerrado is the primary factor impacting the structure of drosophilid assemblages. Nevertheless, disturbance explained the differences in assemblage structure between the conserved and disturbed forests. Even low disturbance levels in forests could cause a decrease in heterogeneity and begin to impoverish these environments, leading to the biotic homogenisation of this currently rich biome. [ABSTRACT FROM AUTHOR]