Abstract
This study reports the first record of unusual pigmentation and morphological anomalies in four flatfish species, Cynoglossus arel, C. lingua, Dagetichthys commersonnii, and Pseudorhombus triocellatus, collected from Indian waters. Unusual pigmentation included ambicolouration in C. arel and D. commersonnii. Morphological anomalies such as fin cuts, caudal deformities, accessory fins, and vertebral fusion were observed in C. arel, C. lingua, and P. triocellatus. These anomalies may indicate developmental stress or environmental disturbance, potentially affecting individual fitness and survival because functional morphology influences ecological performance. Comprehensive, multidisciplinary research is essential to identify specific causes, assess ecological consequences, and prepare conservation strategies.
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