Biodiversity, Ephemeroptera, Description, Distribution
In order to contribute to the knowledge of the biodiversity of the order Ephemeroptera in the metropolitan region of Santarém, the first survey of the group was prepared. Species collection was carried out in 30 aquatic ecosystems distributed in the region, in the period from 2019 to 2020. For the collection of nymphs, rapichés and sieves were used, in addition to manual collection. The winged specimens were collected with the aid of light traps and flight interception, in addition, a bibliographic survey of the species records for the region was carried out through consultations with the Taxonomic Catalog of the Fauna of Brazil, Ephemeroptera of South America and scientific articles. Two chapters resulted from this research. In chapter I, a survey of the group's biodiversity was carried out, which made it possible to list eight families, 32 genera and 51 species / morpho-species, with 13 new records for Pará and 21 for the metropolis of Santarém. Baetidae and Lepthophlebidae were the most representative families. Cloeodes, Hermanellopsis and Tupiara are registered for the first time for Pará and Leptohyphodes are registered for the first time for the North region. In chapter II, a description of a new species of Tricorythopsis based on nymphs was carried out, collected in Santarém and Mojuí dos Campos, Pará municipalities. The present study shows the importance of work with surveys, since it contributes to the knowledge of biodiversity, both in terms of understanding the geographic distribution of taxa, and for the description of many new species.