Chondrostoma esmaeilii Eagderi, Jouladeh-Roudbar, Birecikligil, Çiçek & Coad, 2017

Distribution in the area. Endemic. Known only from the Sarab-e Ravansar stream in Iran.

Taxonomic notes. Based on its description (Eagderi et al. 2017), C. esmaeilii is very different from all other Chondrostoma species. However, the authors did not consider that this species might be the hybrid between Chondrostoma regium and Squalius sp. Hybrids between Chondrostoma and Squalius are well known from other areas in the Palearctic and are superficially very similar to C. esmaeilii . Future research might review the case and test, if these are first-generation hybrids or even a species of hybrid origin. For the time being, C. esmaeilii is accepted as a valid species.