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The Brazilian savanna is the second largest ecosystem in Brazil. It is also one of the most endangered, with only 20% of its habitat remaining unchanged. Agriculture and livestock have been indicated as the main agents of destruction of the Brazilian savanna. Brazilian livestock, for example, is the main reason for cultivation of exotic grasses such as Urochloa spp. (from Africa). Dung beetles are widely used in ecological assessment, mainly because they are recognized as bioindicators of environmental changes. Therefore, efficient sampling is required for any research involving the biodiversity of this group. In order to mitigate the lack of information on efficiency of the attractiveness of baits in the endangered Brazilian savanna and in exotic pasturelands, we sampled dung beetles in four native patches of the Brazilian savanna and in four areas of pastures with Urochloa spp. Dung beetles were captured with pitfall traps baited with carcass, cattle dung, human feces and pig dung, with a total sampling effort of 384 traps. We sampled 7544 individuals belonging to 43 species and 18 genera of dung beetles. Thirty‐eight species were collected in the Brazilian savanna and 24 species in exotic pastureland. In both ecosystems traps baited with human feces sampled greater abundance and species richness of dung beetles when compared with the other three baits used. Our results showed that human feces is a reliable, easy and inexpensive bait to sample greater abundance and species richness of generalist dung beetles in both native and exotic habitats, with clear structural differences.

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ResumoPachycoris torridus (Hemiptera: Scutelleridae) é relacionado como uma praga de frutos e de sementes na cultura do pinhão-manso (Jatropha curcas L.). Este trabalho teve por objetivo estudar os aspectos biológicos e os danos que essa espécie pode ocasionar nessa cultura. Ovos, ninfas e adultos de P. torridus foram coletados e levados a laboratório, onde foram mantidos em câmaras climatizadas para estudo de aspectos biológicos. Para avaliação dos danos, adultos foram confinados em gaiolas no campo, contendo frutos em desenvolvimento. As posturas obtidas tinham em média 57,6 ovos. O período embrionário durou 12,7 dias, enquanto as ninfas de primeiro ao quinto ínstar duraram, respectivamente, 8,1; 10,9; 9,7; 11,6 e 11,7 dias. Da fase de ovo a adulto, o ciclo completou-se em 86,5 dias em média. A cópula durou em média 3h43min. Frutos em desenvolvimento e que receberam uma fêmea, um e dois casais para alimentação, reduziram em 63%; 54% e 85% respectivamente, sua massa, quando comparados com frutos sem percevejos. As sementes formadas em frutos que receberam uma fêmea e um casal apresentaram redução de 99 e 58% no teor de óleo respectivamente. Frutos com dois casais não armazenaram óleo nas sementes. Em frutos desenvolvidos infestados com um casal não se verificou alteração no tamanho e na redução ou alteração da massa, no tamanho e teor de óleo das sementes.Palavras-chave: Jatropha curcas, biologia, Euphorbiaceae, Hemiptera, Scutelleridae. Biological aspects and damage of Pachycoris torridus on physic nut plants AbstractPachycoris torridus (Hemiptera: Scutelleridae) has been reported as a species that can damage fruit and seed of physic nut, Jatropha curcas L. The aim of this study was to evaluate the biological aspects and the damage of this stink bug species on J. curcas. Eggs, nymphs and adults of P. torridus were collected and maintained in a growth chamber. Some adults were confined in cages with developing fruits to damage assessment under field conditions. The postures had an average of 57.6 eggs. The incubation period was 12.7 days and the nymphal stage lasted 8. 1, 10.9, 9.7, 11.6 and 11.7 days for the first, second, third, fourth, and fifth instars, respectively. The development from egg to adult was completed in 86.5 days. The copulation took 3h43min. The presence of one female, one or two couples of stink bug caused decreases of 63, 54 and 85% in fruit weight when compared with control fruit (without insects). Seed oil content was reduced in 99% and 58% when fruits were attacked by a female or a couple. Those fruits with two couples had no oil in seed. For mature fruits, there was not observed any change due to insect presence.

Dung beetles are globally used in ecological research and are useful for assessing the effects of anthropic and natural changes in environment on biodiversity. Here we investigate how the choice of baits (human feces, cattle dung, carrion or a combination of all three) and sampling season influence the taxonomic and functional diversity of insects captured in traps in Brazilian pastures. We sampled dung beetles in July 2011 (dry season) and January 2012 (rainy season) in eight areas: four pastures with native grasses (e.g., Andropogon spp. and Axonopus spp.) and four pastures with introduced grasses (Urochloa spp.) in Aquidauana, Mato Grosso do Sul, Brazil. To collect the insects, we used pitfall traps baited with carrion, cattle dung and human feces. A total of 7,086 dung beetles of 32 species were captured. In both pasture types, only traps baited with human feces captured similar abundance, species richness, and functional diversity compared with the sum total of beetles captured by the three bait types. The species richness and functional diversity were higher in the rainy season in both pasture types. Our results demonstrate that using human feces alone as bait and sampling dung beetles in the rainy season are potentially sufficient to ensure the greatest number of functional traits, species, and individuals in both pasture types. Thus, the best sampling method observed in this study may be useful for studies focused on dung beetle fauna survey and rigorous comparison among studies on these insects in Brazilian pastures.

The Brazilian Cerrado is the second largest Neotropical biome and an important hotspot of biodiversity. However, land use change in this ecosystem is producing landscapes with modified natural environments and anthropogenic environments, such as exotic pastures. In this study, we evaluated how conversion of native Cerrado vegetation to exotic pastures affects the dung beetle assemblages (Coleoptera: Scarabaeidae: Scarabaeinae). We sampled dung beetles in four areas of Cerrado (sensu stricto) and in four areas of exotic pastures (Urochloa spp.) in Aquidauana, Mato Grosso do Sul, Brazil. In all, 7,544 individuals from 43 species of dung beetles were collected, and 19 species were found in both the Cerrado and exotic pastures. The abundance and species richness of dung beetles were higher in Cerrado remnants. Species composition differed between Cerrado and exotic pastures, where 11 species were classified as specialists of Cerrado, 10 species were considered specialists of exotic pastures, and 6 species were habitat generalists. Roller beetles were most negatively affected by exotic pasture establishment. We demonstrated that exotic pasture establishment has a negative impact on dung beetle assemblages in Brazilian Cerrado. The decline in abundance and richness of roller beetles has important implications for the understanding of ecosystem functioning because it can reduce the ecological functions performed by dung beetle assemblages in exotic pastures. Finally, the high number of dung beetle species shared between Cerrado and exotic pastures suggests that the Cerrado remnants is a fundamental requirement for the conservation of biodiversity of dung beetles in exotic pastures in the Brazilian Cerrado.