Cyprinus

Cyprinus is the genus of typical carps in family Cyprinidae. Most species in the genus are of East Asia origin with only the common carp (C. carpio) in Western Asia and Europe; this invasive species has also been introduced to many other regions around the world. Cyprinus are closely related to some more barb-like genera, such as Cyclocheilichthys and Barbonymus (tinfoils). The crucian carps (Carassius) of western Eurasia, which include the goldfish (C. auratus), are apparently not as closely related.

This genus's most widespread and well-known member is the common carp (C. carpio) species complex. Although traditionally considered a single species, recent authorities have split the European and West Asian populations from the East Asian, with the latter named C. rubrofuscus (syn. C. carpio haematopterus). Members of the species complex are famed as a food fish and have been widely traded and introduced since antiquity, but in certain areas has multiplied inordinately and become a pest. In its long use it has been domesticated, and a number of breeds have been developed for food and other purposes. The koi (from Japanese nishikigoi, 錦鯉) are well-known carp breeds, selectively bred for being enjoyed by spectators from above. Strictly speaking, koi is simply the Japanese name of the East Asian carp.