Taxonomia de Stenochironomus Kieffer, 1919 (Diptera: Chironomidae) da Amazônia

Abstract

Stenochironomus Kieffer (Diptera: Chironomidae) is a diverse and cosmopolitan group whose taxonomy is mainly based on the morphology of adult male genitalia. This genus was revised by Borkent (1984), who developed identification keys for larvae, pupae, and adults from the Nearctic, Neotropical, and Palearctic regions. Additionally, the author proposed the subdivision of the genus into two subgenera based on the morphology and habitat of immatures and larvae: Stenochironomus (Petalopholeus) Borkent for leaf-mining species, and Stenochironomus s. str. Kieffer for trunk-mining larvae. There are approximately 112 species of Stenochironomus distributed worldwide (except in Antarctica), of which 39 occur in the Neotropical region and 30 in Brazil, with 27 recorded in the Amazon region. However, some immature stages of Neotropical Stenochironomus are still unknown: among the 39 species described for the region, 24 have described pupae, and 18 have described larvae. Based on this, the present work aims to conduct a taxonomic study of Stenochironomus from the Amazon. To this goal, material from previous collections conducted by the Laboratory of Aquatic Insect Cytotaxonomy (INPA) in the Brazilian Amazon was analyzed. The association with immature stages was made possible through the collection of submerged leaves colonized by Stenochironomus larvae, which were transported to the laboratory for rearing until the emergence of adults. Material collected using Malaise and Pennsylvania traps was also analyzed. As result, eight new species were identified for the genus, of which five were described by associating their developmental stages with males, one was described based on males and pupae, and two were described based solely on males. Furthermore, the distribution of Stenochironomus figueiredoensis Danta, Hamada & Mendes, Stenochironomus liviae Danta, Hamada & Mendes, and Stenochironomus roquei Dantas, Hamada & Mendes was expanded to the state of Acre. Thus, this study contributes to the taxonomic knowledge of Stenochironomus in Brazil, particularly in the Amazon rainforest, by expanding the number of known species in the region.