Micropterus

Micropterus is a genus of North American freshwater fish collectively known as the black bass, which belong to the sunfish family Centrarchidae of order Centrarchiformes. They are sometimes erroneously called "black trout", but the name trout more correctly refers to certain potamodromous members of the family Salmonidae (order Salmoniformes).

Micropterus are widely distributed east of the Rocky Mountains, from the Hudson Bay basin in Canada to northeastern Mexico. Several species, notably the largemouth and smallmouth bass, have been very widely introduced throughout the world, and are now considered cosmopolitan. All black bass species are highly sought-after game fish and well known as strong fighters when hooked, and bass fishing is an extremely popular outdoor sport throughout their native range. Their meat is quite edible and firm, although they are not regarded as commercial food fish.

All black bass species have a dull-green base coloring with dark patterns on the sides. Most reach a maximum overall length of 40–60 cm (16–24 in), but some strains of the largemouth bass have been reported to grow to almost 1 metre (3 ft 3 in) in length. In spawning seasons, the male builds a "nest" (spawning ground) in the bed where a female is induced to deposit her eggs, then the male externally fertilizes them. The male continues to guard the eggs and fry until they disperse from the nest.

Various black bass species have been introduced into freshwater bodies outside North America, where they become invasive in many instances. In Japan, they have been declared nuisance fish and are subjected to numerous attempts at eradicating them from local ecosystems.