Iberochondrostoma almacai

**Algarve Nase (Iberochondrostoma almacai)** The Algarve nase is a small freshwater cyprinid fish endemic to southern Portugal. This slender species typically measures 8-12 centimeters in length, with a streamlined body adapted for life in flowing waters. Like other nase species, it possesses a distinctive inferior mouth with a sharp-edged lower jaw used for scraping algae and biofilm from rocks and substrates. The species plays an important ecological role as both a primary consumer of algae and as prey for larger fish and aquatic predators. The Algarve nase has an extremely restricted range, found only in select river systems within the Algarve region of southern Portugal. It inhabits clear, well-oxygenated streams and small rivers with rocky or gravelly bottoms, typically in areas with moderate to fast-flowing water. This species faces severe threats from habitat degradation and water extraction for agricultural and urban development. Dam construction and river channelization have fragmented populations and altered natural flow regimes essential for the species' survival. Water pollution from agricultural runoff and urban development further compromises water quality in its limited habitat range. Conservation efforts include habitat monitoring and protection measures within Portuguese national conservation frameworks. Some populations occur within protected areas, though enforcement and active management remain limited. The current outlook for the Algarve nase remains precarious. With its critically endangered status and highly restricted range, the species faces significant extinction risk. Without immediate and sustained conservation intervention addressing habitat protection and water resource management, population recovery prospects appear limited.