Lordosis-kyphosis in Argyrosomus regius asso, 1801 obtained from Tripoli, Libya

Abstract

On November 28, 2023, one specimen measuring 344 mm total length and weight 650 g of the atherinid fish Argyrosomus regius displays a continuous incidence of lordosis-kyphosis was obtained from a local fish market in Tripoli, Libya. Externally, the specimen showed one major hunch just behind the head and under the spinous part of the first dorsal fin and another smaller laterally slightly extended hump in the caudal region under the soft part of the dorsal fin. The X-ray examination showed that both the abdominal and the caudal vertebral regions were affected by this anomaly. To describe the case of abnormality, the length of the vertebral column from the anterior end of the first vertebra to the posterior end of the last vertebra was divided by fish total length to make a ratio that was incorporated to compare the abnormal with the normal fish. The values for the nine angles lay between the lines passing through the sides of the vertebral column was obtained. Also, the ratio of the vertebral column to the fish total length of deformed and normal specimens of this species was calculated. Possible causes for these anomalies are considered.