Report on skeletal abnormality in Malabar Grouper Epinephelus malabaricus, from south-east coast of India

This research presents key findings on a unique specimen of grouper, Epinephelus malabaricus, procured from the Gulf of Mannar region, which notably lacks a caudal fin and its associated pterygiophores. A detailed comparison of morphometric and meristic characteristics was conducted between this atypical specimen and a standard specimen. While the body coloration and the majority of morphometric and meristic traits aligned with species descriptions, X-ray analysis confirmed the absence of four terminal vertebrae and the complete caudal complex. The finding highlights the importance of examining morphological variations in marine species, as even the smallest variations can significantly reveal crucial insights into the health of the fish population and its habitat.