It's a species known under the learned name of Epinephelus adscensionis, but in French mérou oualioua. This is one of the many species of grouper still known in English-speaking countries as rock hind. Its Creole name is Grand-gueule, but it can also be found in the USA, Bermuda and Brazil, among others.
It generally lives in rocky seams (between 1 and 120m), and feeds mainly on crabs, although it also eats fish. It is not a protected species. It is heavily fished, including for sport.
The name Mérou Oualioua is standardized by the Office de la langue française.