Endemic freshwater fishes of Turkey

Abstract

Turkey shows a notable diversity of habitats, with significant variations in altitude, rainfall, temperature, topography and geological history, which is reflected in its richness of biodiversity. Although there are quite a number of publications on the freshwater fish taxonomy, the data set for endemic freshwater fish as assemblages are poor. According to recent findings, a total of 194 endemic freshwater fish species are now recognised within the political boundaries of Turkey. Endemic fish consist of 47.4% of the Turkish freshwater ichthyofauna (409 species). At the family level, the Cyprinidae comprises the greatest number of endemic species (110 species; 56.7% of the endemic species), followed by the Nemacheilidae (31 species; 16.0%), Cyprinodontidae (18 species; 9.3%), Cobitidae (14 species; 7.2%), Salmonidae (12 species; 6.2%), Gobiidae (7 species; 3.6%), Petromyzontidae (1 species; 0.5%) and Clupeidae (1 species; 0.5%). A total of 143 species (73.71%) are found within a single basin. Considering species diversity, the Konya endorheic basin (64.10%) is the richest in endemics, followed by Burdur (52.38%), Büyük Menderes (40.28%), Van Gölü (38.46%) and Antalya (34.00%). IUCN Red List criteria of 194 endemic species that were evaluated, 18 species (9.3%) are CR, 38 species (19.6%) EN, 17 species (8.8%) VU, 12 species (6.2%) NT, 35 species (18.0%) LC, 11 species (5.7%) DD and 59 species (30.4%) NE. In total, 4 (2.1%) of the species which are endemic to Turkey are already extinct. In this study, the endemic freshwater fish fauna is analysed in terms of their systematic, ecology and distribution pattern for inland basins of Turkey.