Tabby cat the flanks and stomach. An "M" shape appears on the forehead, along with dark lines across the cat's cheeks to the corners of its eyes. Mackerels are also called 'fishbone tabbies', probably because they are named after the mackerel fish. Mackerel is the most common tabby pattern. The Classic (also known as "Blotched" or "Marbled") tabby tends to have a pattern of dark browns, ochres and black but also occurs in grey. Classic tabbies have the "M" pattern on their foreheads but the body markings have a whirled or swirled pattern (often called a "bullseye") on the cat's sides. There
Mackerel 21 species in all—18 of those are classified into the genus "Scomberomorus", two into "Grammatorcynus", and a single species into the monotypic genus "Acanthocybium". In addition, a number of species with mackerel-like characteristics in the families Carangidae, Hexagrammidae and Gempylidae are commonly referred to as mackerel. There has been some confusion between the Pacific jack mackerel ("Trachurus symmetricus") and the heavily harvested Chilean jack mackerel ("Trachurus murphyi"). These have been thought at times to be the same species, but are now recognised as separate species. The term "mackerel" is also used as a modifier in the common names of other