Scale deformities in Nile tilapia, Oreochromis niloticus, (Actinopterygii: Cichlidae) from Sudan

Abstract

Scale deformity in Nile tilapia, Oreochromis niloticus, (Actinopterygii: Cichlidae) is reported for the first time from Dongola, north of Sudan. The abnormal scales are fused pairs, with two well-developed foci. Developmental irregularity, probably caused by partially arrested growth, is believed to be the cause of such deformity.