Three new species of Bryophaenocladius Thienemann are described and figured as male imagines: B. urbanus sp. n. from Central Argentina, and B. virgotruncatus sp. n. and B. nasus sp. n. from Argentinean Patagonia. A geometric morphometric analysis was performed to evaluate the taxonomic value of the shape of the anal point in species delimitation. The analysis involved 96 species. As a result, the Bryophaenocladius species showed significant anal point patterns of shape change, recovering three main shape types: rounded, equilateral triangle-shaped, and isosceles triangle-shaped. An identification key of the Bryophaenocladius species from the Neotropical region is provided.

This study assessed the taxonomic and functional diversity of aquatic macroinvertebrate communities in Chacabuco stream, a 5500 ha pioneering open conservation ranch of Nahuel Huapi National Park in Argentina, focusing on the effects of seasonal hydrological regimes along a willow-invaded corridor. Sampling was conducted during the spring of 2018 and the summer and spring of 2019, covering high (spring) and low (summer) water levels. Results showed no significant differences in taxonomic diversity between hydrological periods (p = 0.6), and similar taxonomic diversity during the low- and high-water periods of 2019 due to an extreme drought event. Functional diversity varied significantly (p = 0.009) between hydrological periods, and a significant difference in taxonomic diversity between invasive and native plots (p = 0.0001, R = 0.53) was found, while functional diversity revealed less distinction (p = 0.02, R = 0.08). Functional diversity does not follow the same pattern, showing opportunistic taxa such as predators and collectors equally present during both periods, sign of resilience of these FFGs over the others. This pioneering study in the region highlighted the importance of exploring both taxonomic and functional diversity in riparian ecosystems to assess the impact of seasonal hydrological regimes along a willow-invaded corridor and develop a more comprehensive understanding of riparian ecosystem health.

Barbadocladius is a genus of orthoclad midges endemic to the Andes, currently comprising two described species: B. andinus and B. limay. In this study, we emend the diagnosis of the genus. The male, female, and pupa of B. andinus and the pupa of B. limay are redescribed based on new material from the Patagonian Andes. Morphological analyses exhibited the expected variation typical of pupal traits, while mitochondrial COI sequences showed marked genetic divergence between Patagonian and Peruvian populations. Phylogenetic and NMDS analyses do not indicate a latitudinal genetic structure, but possible cryptic diversity or incipient speciation events are suggested. The absence of intermediate samples limits conclusions about the nature of this divergence. Further integrative studies are needed to clarify the taxonomy and evolutionary history of the genus. Beyond the taxonomic revision, this work provides an example of a population-level genetic analysis in a non-charismatic, non-economically relevant insect group. Such studies are usually restricted to taxa of agricultural, quarantine, or conservation concern. By applying integrative tools to Barbadocladius, we highlight how combining molecular and morphological evidence can reveal hidden diversity even in poorly known, non-model lineages, contributing to a broader understanding of Andean biogeography and evolutionary processes.