Gerromorpha (Insecta: Hemiptera: Heteroptera) da região metropolitana de Santarém, Pará, Brasil

Abstract

Gerromorpha (Insecta: Hemiptera: Heteroptera) comprises semiaquatic, - predatory stink bugs, that inhabit both lentic and lotic environments, usually gliding or walking on water or aquatic plants. Worldwide, more than 2100 species are described, of which 236 are registered in Brazil, with 126 of these species occurring in the North and 85 species in Pará state. These numbers, for Brazil, and especially for the North region and Pará, demonstrate that the knowledge about the diversity and distribution of Gerromorpha is still insufficient, considering the enormous territorial extension of the region. In Pará, there are still areas in need of fauna surveys, such as the metropolitan region of Santarém, which, so far, does not have an inventory for several groups of aquatic insects, including Gerromorpha -, which has been losing natural resources through human activities. Our objective was to reduce the lack of knowledge (Wallacean and Linnean deficits) about this group, inventorying the Gerromorpha fauna of the metropolitan region of Santarém. For this, manual collections were carried out with the aid of aquatic nets in 33 aquatic ecosystems, covering streams, waterfalls, pools, phytotelmata and lakes, between the months of July 2019 and October 2020. As results, we presented a commented and illustrated list of Gerromorpha species occurring in the study area, new records, we expanded the geographic distribution areas of known species and, we described new species. 44 species of Gerromorpha were collected, three new species of the genus Microvelia Westwood, 1834: M. sp. nov. 1, M. sp. nov. 2 and M. sp. nov. 3; two new records were made for Brazil: Microvelia aschnakiranae Makhan, 2014 and Rhagovelia graziae Galindo-Malagón, Morales & Moreira, 2021; two new records for Pará state: Microvelia longipes Uhler, 1894 and Paravelia dilatata Polhemus & Polhemus, 1984, and; 15 new records for the metropolitan region of Santarém: Brachymetra lata Shaw, 1933, B. shawi Hungerford & Matsuda, 1957, Tachygerris adamsoni (Drake, 1942), Microvelia pulchella Westwood, 1834, Rhagovelia brunae Magalhães & Moreira, 2016, R. evidis Bacon, 1948, R. jubata Bacon, 1948, Callivelia conata (Hungerford, 1929a), Oiovelia cunucunumana Drake & Maldonado-Capriles, 1952, Paravelia bullialata Polhemus & Polhemus, 1984, Stridulivelia alia (Drake, 1957), S. stridulata (Hungerford , 1929b), S. strigosa (Hungerford, 1929b), S. tersa (Drake & Harris, 1941b) and S. transversa (Hungerford, 1929b). These results expand the knowledge about Gerromorpha in Pará state by 8% and the knowledge for the metropolitan region of Santarém by 100%; and demonstrate the importance and the need for fauna and taxonomic studies for the real knowledge of our biodiversity, as they can subsidize ecological studies, among others, by naming and understanding the distribution of species.