Levantamento de Platypodinae e Scolytinae (Coleoptera : Curculionidae) em dois estratos verticais na Floresta Nacional do Tapajós, Pará, Brasil

Abstract

The bark beetles of the subfamilies Scolytinae and Platypodinae (Curculionidae) assist in the decomposition of organic matter and nutrient cycling in forest environments. Due to the expansion of agricultural and forestry activities, these beetles have become economically important organisms due to their habit of tunneling galleries in wood and the establishment of a symbiotic fungus, for which they are known as ambrosia and bark beetles. In temperate regions, they cause significant damage to agroforestry systems, resulting in millions of dollars in losses. In monocultures, several studies have linked the preferred height of Scolytinae and Platypodinae to near-ground level. However, little is known about the distribution of these groups in native forests, especially in the Amazon region. Thus, the objective of this study was to assess the richness, diversity, abundance, and seasonality of bark beetles, as well as their vertical distribution in a dense rainforest in the Amazon region, through the trapping of Platypodinae and Scolytinae using light traps. A total of 2,245 insects from the subfamily Platypodinae and 11,094 from Scolytinae were collected, totaling 15 and 89 morphospecies, respectively. Platypodinae and Scolytinae showed a higher number of individuals collected in the canopy compared to the understory. Euplatypus, Platypus, and Costaroplatus were the main genera of Platypodinae found in both strata, while for Scolytinae, the genera Scolytodes, Xyleborus, and Pityophthorus were observed. The richness of Platypodinae was similar in both strata, but higher diversity (H') was observed in the canopy, while Scolytinae exhibited higher richness (S) and diversity (H') in the canopy. There was no significant influence of temperature, humidity, and rainfall on the relative abundance of Scolytinae and Platypodinae. Thus, a stratification of bark beetles in the upper strata can be observed, possibly influenced by factors such as the microclimate associated with the canopy, reproduction, and dispersal.