Polymitarcyidae Banks, 1900 (Insecta, Ephemeroptera) da região oeste do Pará

Abstract

Polymitarcyidae is a family within the order Ephemeroptera, which exhibits a broad geographical distribution worldwide. This group is characterized by wings that do not fold over the body and atrophied mouthparts during the adult phase, while displaying diverse mouthparts and abdominal gills in the aquatic stage. The nymphs of Polymitarcyidae are adapted to a fossorial habit, whereas the adults (imagos) present atrophied legs, with the exception of the forelegs in males. Despite being important organisms in aquatic and terrestrial trophic chains and having a wide distribution across the globe, there remains a gap in knowledge regarding this group, leading to a lack of understanding about the distribution of these organisms (Wallacean deficit), as many areas have yet to be explored, such as the Amazon. Thus, this study represents the first survey of Polymitarcyidae in the western region of Pará, aiming to contribute to the knowledge of this taxon in the area. For this purpose, we collected nymphs and adults at 14 localities across eight municipalities in western Pará. Nymphs were captured using aquatic entomological nets and sieves, while adults were obtained through light traps and flight interception traps. Specimen identification was conducted using identification keys and specialized literature, including articles describing genera and species. Additionally, we utilized online resources such as the Catálogo Taxonômico da Fauna do Brasil, the Ephembrazil platform, and the Ephemeroptera da América do Sul website to determine the distribution of the group. The survey revealed the presence of three genera and 13 species of Polymitarcyidae in the region, including six new records for the state of Pará. These results underscore the importance of biodiversity surveys and the expansion of geographical distribution data for species to enhance our understanding of aquatic fauna, thereby facilitating conservation efforts in their areas of occurrence and, consequently, conserving Amazonian biodiversity itself.