Epinephelus costae, the Golden Grouper, is found throughout the Mediterranean basin and the warmer waters of the Atlantic Ocean.
The genus Epinephelus belongs to the subfamily Epinephelinae, family Serranidae, order Perciformes, class Actinopterygii, phylum Chordata and kingdom Animalia.
The Golden Grouper is a demersal species generally found on sandy, muddy or rocky bottoms at depths varying from 4 metres to 160 metres. It migrates annually to the same site and juveniles tend to form small groups. Its head and body are brownish with darker coloured fins. It is also characterised by two dark lines on the head, one from the lower edge of the eye to the ventral rear edge of the interopercle, and the 2nd line from the dark maxillary streak to the lower edge of the preopercle. Adults are brown or greyish brown with a distinct yellow blotch on body below the spinous dorsal fin.
Epinephelus costae grows to a maximum length of 140 cm. Although the main food for the Golden Grouper is other fish, it also feeds on crustaceans and mollusca. A study on the total fecundity for a female of 47 cm standard length was estimated to be 879,000 eggs.
The Golden Grouper has a total of 11 dorsal spines, between 15 and 17 dorsal soft rays, 3 anal spines and 8 anal soft rays. Its body depth is less than the head length, characterised by its convex interorbital area, angular preopercle and 2 to 3 enlarged serrae at the angle. The middle and lower opercular spines are flat but distinct and the upper spine is not apparent. The upper edge of the operculum is straight or slightly convex. The maxilla (upper and lower jaws) usually reach the vertical rear edge of the eyes, with the ventral edge of the maxilla having a low step. No scales are found on the maxilla. There are 2 rows of teeth on the midlateral part of lower jaw. The lateral body scales are ctenoid (toothed), with auxilliary scales in adults.
The photo of this Golden Grouper was taken at a depth of 20 m outside of the Inland Sea, a natural feature at Dwejra, not far from the famous Azure Window, on Gozo’s west coast.
Photo taken by Brian Azzopardi