Koi — Yamakoshi colour mutants · 15

Domesticated carp whose Niigata colour mutations became a global pond aesthetic -- not a wild goldfish substitute. No. Goldfish descend from Prussian carp (Carassius). Koi are ornamental common carp (Cyprinus carpio) fixed in Niigata. The atlas seeAlso cannot point at goldfish because that id is not in the taxonomy.

Colour mutants were kept in Yamakoshi rice-terrace ponds in the early 1800s. The 1914 Tokyo Taisho exhibition took them national. The ZNA-centred championship that still sets kohaku, sanke and showa as the Gosanke core classes. After the 1960s export boom, Israeli and US growers scaled food-and-ornamental carp. Butterfly fins are largely a non-Niigata aesthetic.

Koi herpesvirus outbreaks from the late 1990s killed whole collections. Quarantine and certified-free stock became the new entry ticket. Common carp are invasive in many rivers and lakes. A show pond is secure; a flood overflow is not a garden anymore. Giverny water lilies host carp in the public mind. The nishikigoi fancy is Japanese; the Impressionist pond is a later cross-reading.