Common names: Black grouper, badejo-quadrado. Conservation status: High vulnerable by the IUCN Red List and in Brazil it was included in the “commercially extinct” list of marine resources in Sao Paulo State (Sao Paulo 2008). Identification: D XI + 15–17; A III +11–13; LL 78–83. The body has 7 or 8 columns of rectangular dark gray blotches. The outer third of the second dorsal, anal and caudal fins are black, edge of preopercle is smooth, without a pronounced lobe in the angle. The maximum length is 133 cm, with maximum body weight of 65 kg (Rocha and Costa 1999). Illustration from FAO species catalogue. Distribution: This species occurs in western Atlantic, from Bermuda and Massachusetts to southern Brazil, including the southern part of Gulf of Mexico, Florida Keys, Bahamas, Cuba and the Caribbean. Habitat and ecology: This species is found on rocky bottoms and coral reefs to depths of at least 75 m. Adults are most commonly found bellow 30 m while juveniles generally occur in shalow waters. Adults feed primarily on fishes and juveniles prey, mainly crustaceans. The black grouper is one of the most important species in Atlantic coast fisheries. In Northeast Brazil, between the States of Ceara and Alagoas, M. bonaci has been caught by artisanal fishery using hooks and lines or compressor-assisted spear fishing (Teixeira et al 2004). Reproduction: This specie is a protogynous hermaphrodite, with reproductive aggregations. Maturing females occur between 50 and 100 cm and mature males between 96 and 116 cm (Heemstra and Randall 1993). Threats: Overfishing. Conservation action: Since 2003, in Brazil a minimum capturing size of capture was established at 45 cm. Conservation recommendation: Environ Biol Fish DOI 10.1007/s10641-010-9634-9