Three new species of Macrelmis Motschulsky, 1859 (Macrelmis bispo sp. nov., Macrelmis froehlichi sp. nov., and Macrelmis nessimiani sp. nov.) are herein described and illustrated. The species were collected from several streams in Goiás State, Brazil, a formerly unknown region concerning Elmidae fauna. We also provide an updated key for the Macrelmis species of Brazil.

Insects are one of the few groups of animals that developed the ability of active flight. Such mobility allowed the group to successfully explore and thrive in nearly all kinds of ecological niches. At the same time, during the evolutionary history of insects, due to high costs of wing development, flight was lost independently in many groups. In beetles, the reduction or complete loss of hind wings has been reported in multiple lineages, especially in several extreme paedomorphic and larviform females, mainly in Elateroidea, in which not only the hind wings but also the elytra are lost. However, the complete absence of elytra in adult males was hitherto unknown, despite nearly half a million described species in Coleoptera. In this study, we report the discovery of Xenomorphon baranowskii gen. et sp. nov., the first completely anelytrous and wingless adult male beetle, belonging to the family Lycidae (Coleoptera: Elateroidea). Xenomorphon baranowskii is illustrated, described, and provisionally placed in Calopterini, based on our morphology-based phylogenetic analyses. We discuss the possible scenarios that could lead to such a rare event, when a beetle loses its elytra, and its evolutionary consequences.

ABSTRACT. A taxonomic key for the genera of Elmidae (Coleoptera, Byrrhoidea) occurring in Goiás State, Brazil, including new records and distributional notes. Despite their great diversity and high abundance in Neotropical aquatic environments, the fauna of Elmidae remains practically unknown in some areas and even entire biomes in this region. In this work we bring, for the first time, faunistic data for the Elmidae of central Brazil. The aim of this work was to inventory the Elmidae fauna in central, southwestern and southeastern Goiás State, Brazil and to produce a taxonomic key, at genus level, for adults from the studied region. The taxonomic key presented herein offers means for the identification of all the 13 genera known to occur in Goiás, 11 of them being new records for the State. Moreover, the number of named species registered for Goiás increased from one to nine.

This paper deals with the Trichoptera immature fauna collected in 101 streams in Rio das Almas Basin during August-October 2008 and in Rio Paranã, Iaciara-GO municipality, on August 2003, using kick-nets with 0.025 m 2 of opening and 2 mm mesh. We record four new genera for Goiás State, expanding records of genera from 33 to 37 and contributing to the Trichoptera fauna knowledge in Central Brazil.

The genus Balgus Fleutiaux 1920 was currently comprised of nine species and can be easily distinguished from other Thylacosterninae by the presence of tubercles on the pronotal disk. In this paper a taxonomic revision and a reconstruction of the phylogeny of the genus were performed. Morphological data were analyzed using maximum parsimony (MP) and by Bayesian inference (BI). For BI the Mkv model was used. The genus Balgus and eight of the nine species were redescribed. The subspecies B. schnusei cayennensis Chassain, 2003 was considered a synonym of B. schnusei (Heller, 1914), and the genus was considered monophyletic. An identification key to all species of the genus was generated.