First record and distribution of the blue tilapia, Oreochromis aureus (Steindachner, 1864) (Perciformes: Cichlidae) in inland waters of Iran

The blue tilapia, Oreochromis aureus (Steindachner, 1864) is recorded for the first time from the Arvand and Karun River drainages in Khuzestan province, Iran. This species is the second tilapia fish, recorded and confirmed by specimens from natural water bodies of Iran. The relative abundance and location records of the observed blue tilapia are presented. As tilapia species have high resistance for different environmental conditions and can easily propagate in new habitats, thus its monitoring is highly recommended.