ABSTRACT
This is the first study to address the dung beetle (Coleoptera: Scarabaeidae: Scarabaeinae) diversity in intra-Amazonian savannahs in the state of Roraima, Brazil. Our aim was to survey the dung beetle fauna associated with these savannahs (regionally called 'lavrado'), since little is known about the dung beetles from this environment. We conducted three field samples using pitfall traps baited with human dung in savannah areas near the city of Boa Vista during the rainy seasons of 1996, 1997, and 2008. We collected 383 individuals from ten species, wherein six have no previous record in intra-Amazonian savannahs. The most abundant species were Ontherus appendiculatus (Mannerheim, 1829), Canthidium aff. humerale (Germar, 1813), Dichotomius nisus (Olivier, 1789), and Pseudocanthon aff. xanthurus (Blanchard, 1846). We believe that knowing the dung beetles diversity associated with the intra-Amazonian savannahs is ideal for understanding the occurrence and distribution of these organisms in a highly threatened environment, it thus being the first step towards conservation strategy development.
Este é o primeiro estudo da diversidade de besouros rola-bosta (Coleoptera: Scarabaeidae: Scarabaeinae) nas savanas intra-amazônicas de Roraima, Brasil. Nosso objetivo foi inventariar a fauna de besouros associada com savanas (conhecidas regionalmente como 'lavrado'), uma vez que pouco se sabe sobre esses besouros nesse ambiente. Nós amostramos em savanas próximas a cidade de Boa Vista durante a estação chuvosa nos anos 1996, 1997 e 2008, utilizando armadilhas pitfall iscadas com fezes humanas. Coletamos 383 indivíduos de dez espécies, das quais seis não haviam ocorrência prévia para savanas intra-amazônicas. As espécies mais abundantes foram Ontherus appendiculatus (Mannerheim, 1829), Canthidium aff. humerale (Germar, 1813), Dichotomius nisus (Olivier, 1789) e Pseudocanthon aff. xanthurus (Blanchard, 1846). Nós acreditamos que conhecendo a diversidade de besouros associada ès savanas intra-Amazônicas se torna ideal para o entendimento da ocorrência e distribuição desses organismos em um ambiente altamente ameaçado, sendo o primeiro passo para a tomada de estratégias de conservação.
ABSTRACT
Dung beetles (Coleoptera, Scarabaeinae) attracted to sheep dung in exotic pastures. In this study we provide data on the abundance and richness of dung beetles (Coleoptera, Scarabaeidae, Scarabaeinae) attracted to sheep dung in exotic pastures (Brachiaria spp.). In four areas of exotic pasture pitfall traps were installed and baited with fresh sheep dung for sampling of dung beetles. A total of 2,290 individuals were captured belonging to 16 species, 10 genera and five tribes of Scarabaeinae beetles. Trichillum externepunctatum Preudhomme de Borre, 1886 and Dichotomius bos (Blanchard, 1843) were dominant. The guild of dwellers was the most abundant in pastures. We demonstrate that dung beetles are attracted to sheep dung. Since the production of both cattle and sheep in the same area is common in tropical pasturelands, results obtained here highlight the need to investigate the actual role of dung sharing (cattle dung + sheep dung) by dung beetles. It is also suggested that experiments be performed for evaluation of the ecological functions performed by dung beetles using sheep dung.