The beetles are extremely important comodecompositores, natural enemies of coprobiontes pests and environmental indicators. They are very useful for livestock agroecosystems, acting in the disorganization of faecal masses and animal carcasses, contributing to the natural biological control of bovine parasites that develop in these materials. However, no work was done on the Rio Grande do Sul Campaign Region regarding the response of these beetles to a natural ecotone of forest and field that supplies. Thus, a survey of Scarabaeidae strictosensu was carried out in this ecotone at the Rural Campus of the University of Camaguey Region, Bagé, during the month of October 2007. Eighteen pitfall traps distributed in three transects were used, being nine traps in each environment, baited with fecalfresca mass and liver in decomposition of cattle. There were three collections with a 48h wait and one after 120h. 250 beetles of 16 species were captured. The most abundant species were Canthon rutilans Laporte, 1840 (131 individuals) and Ateuchus aff. robustus Harold, 1868 (39 individuals). The forest area presented more species and individuals than the field area and the border area. However, the border area presented higher diversity indexes than the other ecosystems. The presence of the border had an effect as marked as the type of environment in the abundance and distribution of the species of Scarabaeidae collected. A new species was registered for the municipality of Bagé. There were three collections with a 48h wait and one after 120h. 250 beetles of 16 species were captured. The most abundant species were Canthon rutilans Laporte, 1840 (131 individuals) and Ateuchus aff. robustus Harold, 1868 (39 individuals). The forest area presented more species and individuals than the field area and the border area. However, the border area presented higher diversity indexes than the other ecosystems. The presence of the border had an effect as marked as the type of environment in the abundance and distribution of the species of Scarabaeidae collected. A new species was registered for the municipality of Bagé. There were three collections with a 48h wait and one after 120h. 250 beetles of 16 species were captured. The most abundant species were Canthon rutilans Laporte, 1840 (131 individuals) and Ateuchus aff. robustus Harold, 1868 (39 individuals). The forest area presented more species and individuals than the field area and the border area. However, the border area presented higher diversity indexes than the other ecosystems. The presence of the border had an effect as marked as the type of environment in the abundance and distribution of the species of Scarabaeidae collected. A new species was registered for the municipality of Bagé. robustus Harold, 1868 (39 individuals). The forest area presented more species and individuals than the field area and the border area. However, the border area presented higher diversity indexes than the other ecosystems. The presence of the border had an effect as marked as the type of environment in the abundance and distribution of the species of Scarabaeidae collected. A new species was registered for the municipality of Bagé. robustus Harold, 1868 (39 individuals). The forest area presented more species and individuals than the field area and the border area. However, the border area presented higher diversity indexes than the other ecosystems. The presence of the border had an effect as marked as the type of environment in the abundance and distribution of the species of Scarabaeidae collected. A new species was registered for the municipality of Bagé.
