Diversity of anthophile insects in an area with eucalypt plantations in the municipality of Triunfo, Rio Grande do Sul, Brazil

The result of habitat fragmentation has been assessed through measuring of richness and diversity of some functional groups, especially flower-visiting insects. These organisms allow functional connectivity between plantations and protected areas and the restoration of disturbed environments. This study aimed to analyze the diversity of anthophilous insects on transects established between a gallery forest and the eucalyptus reforestation and exclusively among a section of eucalyptus trees in south Brazil. Insects collected belonged to the orders Hymenoptera, Lepidoptera, Diptera, Coleoptera and Hemiptera. Insect abundance was low compared to other studies. Twenty-eight species were found in both environments, whereas 138 were restricted to one environment (61 in gallery forest/eucalyptus, and 77 in eucalyptus/eucalyptus). Insects visited flowers of 31 plants species distributed in 20 families. In both environments, there were a few dominant species and a large number represented by a single individual. A similarly high diversity was found in both environments (H' = 4.084 and H' = 4.018). Among insects, bees showed the highest diversity in environments gallery forest/eucalyptus (H' = 3.211) and eucalyptus/eucalyptus (H' = 2.8). Despite the similarity in community structure between these environments, their fauna of anthophilous insects differ in species composition and the number of individuals of those shared species.