Koi
The major named varieties include:Goldfish (金魚) were developed in China more than a thousand years ago by selectively breeding Prussian carp for color mutations. By the Song dynasty (960–1279), yellow, orange, white, and red-and-white colorations had been developed. Goldfish ("Carassius auratus") and Prussian carp ("Carassius gibelio") are now considered different species. Goldfish were introduced to Japan in the 16th century and to Europe in the 17th century. Koi, though, were developed from common carp in Japan in the 1820s. Koi are domesticated common carp ("Cyprinus carpio") that are selected or culled for color; they are not a different species, but a subspecies, and will revert to the original coloration within a few generations if allowed to breed freely.
Synchiropus splendidus
The mandarinfish was first described as "Callionymus splendidus" in 1927 by Albert William
Herre, an American ichthyologist working in the Philippines. It was later placed in genus "Synchiropus". The generic name "Synchiropus" is from Ancient Greek "syn-", meaning "together", and "-chiropus" meaning "hand-foot". The specific epithet "splendidus" is from the Latin for 'bright' or 'glittering.'
The common name of the mandarinfish comes from its extremely vivid colouration, evoking the robes of an Imperial Chinese mandarin.
Other common names include mandarin goby, green mandarin, striped mandarinfish, striped dragonet, green dragonet and sometimes psychedelic mandarinfish.
The similarly named mandarin fish ("Siniperca chuatsi"), properly known as the Chinese perch, is distantly related.