Arthropods associated to tree canopies in the edges of a forest fragment in the Cerrado of Minas Gerais, Brazil

Abstract

The Cerrado biome occupies 22% of Brazil's land area and has one of the highest levels of endemism of flora and fauna species of any biome. As components of the fauna, the arthropods stand out as they perform several functions within ecosystems and serve as bioindicators of environmental quality. This work aimed to evaluate the association of the arthropod fauna with tree canopies in an area surrounding a fragment of a legal reserve adjacent to a coffee plantation. The study was conducted at the Juliana farm (18°43'29"S; 47°29'55"W), located in the municipality of Monte Carmelo, Minas Gerais, Brazil. The canopy net methodology was used, in which a net bag was wrapped around the branches and shaken five times, covering the four cardinal directions in the crowns of 20 trees. The contents of the net were placed in plastic bags, sealed, identified, and taken to the laboratory. Twelve monthly collections were performed between August 2018 and July 2019, for a total of 240 samples. The collected specimens were identified in taxonomic groups using a taxonomic key. During the sampling period, 804 individuals were collected, belonging to 56 taxa of the classes Arachnida and Insecta. Xylopia aromatica (Annonaceae) was the most representative tree species, with 50% of the sampled taxa found in its branches. The order Araneae and the families Asilidae and Tephritidae (Diptera) and Formicidae (Hymenoptera) were the predominant taxa in the faunistic analysis. As potential predators, Araneae and Formicidae were the most important groups and were found in all tree species sampled. The families Braconidae and Ichneumonidae (Hymenoptera) were the most common among the parasitoids. We conclude that the legal reserve and permanent preservation areas maintain populations of tree species that can generate a survival site for natural enemies and other canopy arthropods.