Contribution to the knowledge of spiders (Araneae) of the upper course of the Neretva River in Bosnia and Herzegovina

The upper course of the Neretva River, located in the rugged landscapes of Bosnia and Herzegovina (BiH), hosts a unique and largely unexplored ecosystem with significant biodiversity. This study aims to document the spider (Araneae) species inhabiting this region, including the Neretva’s wider catchment area, Nevesinjsko polje, and the Vranjača cave. Using various sampling methods, we identified 84 spider species from 72 genera and 22 families, with 50 (60%) species reported in BiH for the first time. Notable findings include the abundant Piratula knorri (Scopoli, 1763) (Lycosidae), and cave-dwelling species such as a region endemic Parastalita stygia (Joseph, 1882) (Dysderidae) and Lepthyphantes leprosus (Ohlert, 1865) (Linyphiidae). Our results emphasise the importance of this understudied region for spider biodiversity and underscore the need for ongoing research to enhance faunistic knowledge and inform conservation efforts in BiH.