Comunidade de Coleoptera em duas fitofisionomias de caatinga no Estado da Paraíba, nordeste do Brasil : composição, diversidade, variação sazonal e grupos tróficos

Abstract

The Caatinga is an important Brazilian ecosystem, due to its biodiversity, endemism and climatic peculiarities, however, its beetles fauna is little known. Therefore, this study evaluated the structure, seasonal variation and trophic groups of the community of Coleoptera of two phytophysiognomies present in the semiarid Caatinga region, sampled by malaise trap in two Caatinga phytophysiognomies, one of xerophytic vegetation and one of riparian forest, weekly, during four years. The results showed a rich fauna of beetles, composed of 383 species and 42 families. The riparian forest presented greater richness and abundance in relation to the xerophytic vegetation. Although present in a region with high average temperatures and a prolonged rainfall period, the sample close to the riparian forest did not show a significant seasonal variation for species richness and abundance of beetle individuals, contrary to what was observed for the xerophytic vegetation environment, in which an evident reduction pattern was registered for both parameters in the dry seasons. The variation in the number of individuals of the species was the main responsible for the difference observed in the composition of the coleopterofauna, considering jointly the dry and rainy season, among the phytophysiognomies. Herbivores, carnivores, detritivores and fungivores were the trophic groups collected, being registered distinct seasonal pattern of the groups during the dry period between areas with an increased in abundance in the riparian forest in that season, except for carnivores. In view of the results found, the importance of the riparian forest to the beetle community in the Brazilian semiarid region was evident, especially during the dry season, corroborating the hypothesis of acting as a refuge during the dry season. The present study contributes to the knowledge of the fauna of Coleoptera in the Semiarid of Brazil, and consequently to the Northeast, bringing a general list of species of beetles.