Is Capoeta aculeata (Valenciennes, 1844) a proper Biological indicator for water quality assessment in Khorram-Rud River?

In order to investigate phenotypic abnormality in Khorram-rud River in Lorestan province in Iran, 1982 specimens including 13 species were caught. For this purpose, 8 sites were chosen on Khorram-rud River in Khorramabad city from 10 Km upstream to 10 km downstream of the city. Fish were caught using a cast net. Most of the sampled fish were returned to the river if there were no phenotypic abnormalities. A total of 21 cases of phenotypic abnormalities were observed among Capoeta aculeata, while no cases of phenotypic abnormalities were observed among other species. The observed phenotypic abnormalities in this study can be classified into three general categories including Caudal Deformity Syndrome, semi-operculum, and unidentified tissue lesions. Finally, due to the entrance of various urban, industrial, and agricultural pollutants into the Khorram-rud River and the high frequency of phenotypical abnormalities in C. aculeata, this fish can be proposed as a biological indicator for water pollution monitoring in the Khorram-rud River.