Short answers, pulled from the story.
The Atlantic mackerel bears the Latin name Scomber scombrus and is sometimes referred to as punctualis piscis or punctual fish. This name reflects the fish's punctual movement from warm to cold waters with clockwork precision during mating season.
True mackerels belong to the tribe Scombrini and consist of seven species split between two genera: Scomber and Rastrelliger. The type species for scombroid mackerels is the Atlantic mackerel, Scomber scombrus.
Until 1999, the Atlantic chub mackerel and Indo-Pacific chub mackerel were thought to be subspecies of the same species. Molecular and morphological studies by Collette proved they were separate species in 1999.
The Wahoo can reach speeds of up to 70 miles per hour, which is significantly faster than the Atlantic mackerel. Atlantic mackerel are capable of sustained speeds of 0.98 meters per second and burst speeds of 5.5 meters per second.
In 2009, over 5 million tons of mackerel were landed by commercial fishermen. Chub mackerel and Atlantic mackerel together account for about 75% of the total catch of scombroid mackerels.
Mackerel was regarded as unclean in the UK and other places due to folklore which suggested that the fish fed on the corpses of dead sailors. A 1976 survey of housewives in Britain undertaken by the White Fish Authority indicated a reluctance to buy the fish.