Some deformities noticed in the indian mackerel, Rastrelliger kanagurta (Cuvier)

Abstract

Eight spscimens of abnormal mackerel caught at Cochin are described. Three of them had deformed tails. One was hunchbacked. Two had unusually long mandibles, while another one had a short mandible and a freak maxilla. The last specimen had an anomalous anal fin. The occurrence of abnormality was one in eight hundred. Irregularity in the caudal region was the most common abnormality.