Blue Runner - Taxonomy and Naming

Taxonomy and Naming

The blue runner is classified within the genus Caranx, one of a number of groups known as the jacks or trevallies. Caranx itself is part of the larger jack and horse mackerel family Carangidae, a group of percoid fishes in the order Perciformes.

The species was first scientifically described by the American ichthyologist Samuel L. Mitchill in 1815, based on a specimen taken from the waters of New York Bay, USA which was designated to be the holotype. He named the species Scomber crysos and suggested a common name of 'yellow mackerel', with the specific epithet reflecting this, meaning "gold" in Greek. The taxon has been variably placed in either Caranx, Carangoides or Paratractus, but is now considered valid as Caranx crysos. The species has been independently redescribed three times, first as Caranx fusus, which is still incorrectly used by some authors (occasionally as Carangoides fusus), and later as Caranx pisquetus and Trachurus squamosus. These names are considered invalid junior synonyms under ICZN rules. The species has many common names, with the most common being 'blue runner'. Other less commonly used names include 'bluestripe jack', 'Egyptian scad', 'hardtail jack', 'hardnose', 'white back cavalli', 'yellow tail cavalli', as well as a variety of broad names such as 'mackerel', 'runner' and 'crevalle'.

There has been suggestions that the blue runner may be conspecific with the eastern Pacific species Caranx caballus (green jack), although no specific studies have been undertaken to examine this relationship. Both species were included in a recent genetic analysis of the entire Carangidae family, with results showing both species are very closely related, although the authors did not comment on genetic distance between the two.