Cisco (fish)
The ciscoes (or ciscos) are salmonid fish of the genus Coregonus that differ from other members of the genus in having upper and lower jaws of approximately equal length and high gillraker counts. These species have been the focus of much study recently, as researchers have sought to determine the relationships among species that appear to have evolved very recently. The term cisco is also specifically used of the North American species Coregonus artedi, also known as lake herring.
In previous taxonomic classifications, the ciscoes have been identified as a subgenus Leucichthys of the genus Coregonus. Based on molecular data this is not a natural classification however, but the ciscoes are polyphyletic, comprising two different lineages within the freshwater whitefishes.
Read more about Cisco (fish): Continental North American Ciscoes: Coregonus Artedi Sensu Lato, Ciscoes of Northwestern North America, Eurasian Ciscoes, Phylogeny