Dusky grouper
(Epinephelus marginatus)

Epinephelus marginatus, the dusky grouper, yellowbelly rock cod or yellowbelly grouper, is a species of marine ray-finned fish, a grouper from the subfamily Epinephelinae which is part of the family Serranidae, which also includes the anthias and sea basses. This species is the best-known grouper species of the Mediterranean Sea and North Africa coast.

Description
Epinephelus marginatus is a very large, oval-bodied and large-headed fish with a wide mouth which has a protruding lower jaw. The head and upper body are coloured dark reddish-brown or greyish, usually with yellowish gold countershading on the ventral surfaces; the base colour is marked by a vertical series of irregular pale greenish-yellow or silvery grey or whitish blotching which is normally rather conspicuous on the body and head; the black maxillary streak varies in its markedness; dark brown median fins; distal edges of the anal and caudal fins and also often pectoral fins have narrow white terminal bands; the pelvic fins are black towards their tips while the pectoral fins are dark reddish-brown or grey; the margin of the spiny dorsal fin and basal part of the pectoral fins are often golden yellows in colour. There are eleven spines and 13-16 soft rays in the dorsal fin.

This species can grow up to 150 cm in standard length but is more often 90 cm.

Distribution
Epinephelus marginatus has two disjunct distribution centres, the main one is in the eastern Atlantic from the west coast of Iberia south along the western coast of Africa to the Cape of Good Hope, extending east into the south-western Indian Ocean, as far as southern Mozambique, with doubtful records from Madagascar and possibly Oman. It is found throughout the Mediterranean too. The second population occurs in the southwestern Atlantic off the coast of South America in southern Brazil, Uruguay and northern Argentina. In the eastern Atlantic it is not normally found further north than Portugal but there have been rare records from the Bay of Biscay and in the English Channel as far north as northern France, Great Britain and Ireland.

Habitat
Epinephelus marginatus is demersal, normally found in and around rocky reefs from surface waters down to as much as 300 metres in depth. It often occurs in the vicinity of beds of Poseidonia seagrass. Juveniles are generally found more inshore than adult fish, even being found in rock pools. Where they are protected, in marine nature reserves and no-take zones, both adults and juveniles occur in shallow waters, but the depths at which juveniles are found is always shallower than the preferred depths of adults.