Plecoptera and Trichoptera species in the Upper Neretva Catchment (Bosnia and Herzegovina) – new data from 2023 supplement the high diversity recorded a year beforeTeufl, Pia (Avtor) Graf, Wolfram (Avtor) NeretvabiodiversitycaddisfliesstoneflieshydropowerThe Balkan Peninsula is considered to be a biodiversity hotspot, hosting a particularly high number of endemic species. Despite increased faunistic research in recent decades many areas remain poorly investigated, particularly regarding the aquatic entomofauna. The order Plecoptera, for instance, is strongly associated with cold, well-oxygenated mountain rivers and is known for its high sensitivity to environmental change. Consequently, stoneflies serve as valuable bioindicators in environmental monitoring. Similarly, the order Trichoptera includes many species with high habitat specificity, which are vulnerable to habitat degradation. A comprehensive understanding of the region's species inventory is essential, not only to deepen the knowledge about the distribution and habitat preferences of endemic and rare species, but also to assess what is at stake in case of significant environmental changes, such as those caused by hydropower development. To address these gaps in our knowledge, faunistic surveys focusing on Plecoptera and Trichoptera were conducted in 2022 and 2023 along the upper reaches of the Neretva River and its tributaries Krupac, Ljuta, and Jezernica as well as smaller, unnamed brooks within the catchment. Here we report the results from 2023 and compare them to the data published in 2022; both surveys conducted as part of the Neretva Science Week. We aim to contribute to the broader understanding of species diversity, distribution, and abundance of Plecoptera and Trichoptera in this area.20252026-03-15 10:34:22Članek v reviji180726sl