A new genus, Tupadesmus (Polydesmida, Chelodesmidae), and a new species, T. muyrakyta (type species for the genus) are herein described from the Amazon rainforest of northern Brazil. Tupadesmus pugiunculus (Schubart, 1946), new combination, is placed in the new genus. We compared the new genus with other Chelodesminae taxa, in particular with Eucampesmella, Brachyurodesmus and Arthrosolaenomeridini. Males of the genus Tupadesmus differ from those of other Chelodesmidae genera by the presence of well-defined striations surrounding incisura lateralis and by the gonopodal prefemoral process divided into two thin, elongate, subequal and acuminate branches. An updated checklist of the Chelodesmidae of Pará State, Brazil, is also provided.

Smicridea McLachlan, 1871, is the richest genus of Hydropsychidae in the New World, with its subgenus Smicridea (Smicridea) being the most diverse, comprising 145 species. However, immature stages of only 13% of these species have been described. In Brazil, only five of 29 species of S. (Smicridea) have documented immature stages. To fill this gap, we describe and illustrate the larva and pupa of S. (Smicridea) erecta Flint, 1974. Using the metamorphotype method, we associated adults with their immature stages. Larvae of S. erecta are characterized by ten dark brown oval muscular scars on the posterior region of the frontoclypeus, arranged in a boomerang shape, and a convex and entirely crenulate anterior margin. The pupa exhibits pairs of hook plates exclusively on the abdominal terga of segments II–VI. This study adds to the understanding of Smicridea (Smicridea), making Smicridea (Smicridea) erecta the sixth species in Brazil and the twentieth globally with documented immature stages.

A new species of the snail-case caddisfly, Helicopsyche (Feropsyche) imperial Silva-Pereira, Desidério, Pereira & Hamada subgenus Helicopsyche (Feropsyche), is described and illustrated based on adult males from a protected and preserved area in the Cerrado biome in Federal District, Central West Region, Brazil. The new species can be recognized mainly by the morphology of tergum X in the dorsal view and inferior appendages in the ventral view. In addition, new records are provided for H. (Feropsyche) vergelana and H. (Cochliopsyche) opalescens. The discovery of the new species and the new record of H. vergelana are the first records of H. (Feropsyche) from the Central West Region of Brazil.

Many associations with microbial species significantly affect the biology, ecology and evolution of the host. Yet, our understanding of the species composition of the gut microbiota remains limited for many host species. Here, we provide a new step towards filling this gap, and characterize the bacterial microbiota of 60 specimens of Lithobius forficatus, a brown stone centipede commonly found in Finland. Many specimens analysed in this study were found to have a very species-rich bacterial community, while others hosted communities clearly dominated by one bacterial species. The most abundant phylotypes included some potential pathogens such as Borrelia and Pseudomonas, a honeybee gut symbiont Gilliamella and some maternally inherited symbiotic bacteria, including Wolbachia and Rickettsiaceae. While females and males were found to carry similar bacterial communities, population had a significant effect on the bacterial community composition. Bacterial species richness did not differ between sexes or between populations in Lithobious forficatus.