Smicridea (Rhyacophylax) Müller 1879 contains 106 species, 41 of which occur in Brazil, mainly in the Atlantic Forest biome. Despite its diversity, it is estimated that many undescribed species are believed to be housed in scientific collections, waiting to be described. Smicridea specimens housed in two Brazilian insect collections (Coleção Entomológica Professor José Alfredo Pinheiro Dutra, Rio de Janeiro and Museu de Zoologia da Universidade de São Paulo, São Paulo) were examined and two new species of S. (Rhyacophylax) were detected. The objective of this study is to describe and illustrate these species. Smicridea (Rhyacophylax) boraceia sp. nov. and Smicridea (Rhyacophylax) dumasi sp. nov. inhabit the Atlantic forest biome and can be recognized mainly by the morphology of tergum X and the phallic apparatus. Six species groups are recognized in S. (Rhyacophylax); however, the two new species described here cannot be placed in any of these groups.

Os ambientes aquáticos, como rios, lagos e igarapés, são lugares cheios de vida. Neles vivem uma variedade incrível de animais, como diferentes espécies de peixes, camarões, caranguejos e um grupo muito interessante de animais: os insetos aquáticos. Vamos explorar o incrível mundo aquático e conhecer mais sobre alguns insetos?

Despite being the subgenus with the highest number of species within Chimarra Stephens, 1829 in Brazil, information about Chimarra (Curgia) Walker, 1980 is scarce in the Brazilian semi-arid region. Beyond the discussion about the quantity of species reported for this region, there is also a temporal gap concerning original descriptions of this subgenus in Brazil. Thus, 15 years after the last description of C. (Curgia) in Brazil, we diagnosed, described, and illustrated two new species based on adult males collected in the Caatinga and Cerrado biomes in the state of Piauí, viz., Chimarra (Curgia) opala sp. nov. and Chimarra (Curgia) prata sp. nov. They can be recognized mainly by the morphology of tergum X, preanal appendage, and phallotheca spines. Moreover, they do not conform to the characteristics of any species group traditionally known in the genus. While sharing similarities with the species compared in this study, these comparisons are limited to isolated characters and do not encompass all the features representing the groups of their respective species.

The long-horned caddisfly Brachysetodes Schmid, 1955 (Leptoceridae: Leptocerinae) is a small genus endemic to the Andean region, especially Chile. Four decades after the last taxonomic revision, a new species, Brachysetodes tricahue Desidério, Santana & Hamada sp. nov., is described and illustrated based on adult males collected from Parque Natural Tricahue in the Central Subregion of the Chilean Andes. Specimens were examined through genital dissection using heated KOH, photographed with a digital camera mounted on microscopes, and described using the DELTA system. A distribution map was produced in QGIS based on GBIF data and literature records, and an updated identification key to males of the ten known species of Brachysetodes sensu stricto is presented. B. tricahue sp. nov. closely resembles B. bifurcatus and B. nublensis, sharing key features such as paired lateral processes on tergum X and tripartite inferior appendages. However, it can be distinguished by a unique combination of genital features, including unequal lengths of the three processes of the inferior appendage. This discovery emphasizes the underexplored diversity of the southern Andes and contributes to refining the taxonomy and biogeography of the genus. It also provides a framework for future phylogenetic studies incorporating immature stages and molecular data.

Despite being the subgenus with the highest number of species within Chimarra Stephens, 1829 in Brazil, information about Chimarra (Curgia) Walker, 1980 is scarce in the Brazilian semi-arid region. Beyond the discussion about the quantity of species reported for this region, there is also a temporal gap concerning original descriptions of this subgenus in Brazil. Thus, 15 years after the last description of C. (Curgia) in Brazil, we diagnosed, described, and illustrated two new species based on adult males collected in the Caatinga and Cerrado biomes in the state of Piauí, viz., Chimarra (Curgia) opala sp. nov. and Chimarra (Curgia) prata sp. nov. They can be recognized mainly by the morphology of tergum X, preanal appendage, and phallotheca spines. Moreover, they do not conform to the characteristics of any species group traditionally known in the genus. While sharing similarities with the species compared in this study, these comparisons are limited to isolated characters and do not encompass all the features representing the groups of their respective species.