It was previously thought that all Japanese carp were introduced from China in prehistoric times. However, recent analysis of mitochondrial DNA revealed a significant evolutionary divergence (phylogenetic split) within common carp Cyprinus carpio between the native wild form found in Lake Biwa and the Eurasian wild form, along with domesticated varieties. This supports the idea of the ancient origin of the native Japanese form (Cyprinus sp.), as well as the East Asian ancient lineage of wild common carp (C. carpio), previously proposed on the basis of fossil data. However, it is unknown when the carp from the continent was introduced to Japan. In addition, a possible multiple origin of koi carp was indicated by the polyphyletic distribution of five mtDNA haplotypes of koi carp within the ‘Eurasian’ clade. Moreover, the oldest record of the introduction of non-native fish in Japan is that of goldfish from China (1502 or 1602), and there is no record of carp (including colored carp) until the introduction of the mirror carp, called Doitsugoi (German carp), in 1904.
It was previously thought that all Japanese carp were introduced from China in prehistoric times. However, recent analysis of mitochondrial DNA revealed a significant evolutionary divergence (phylogenetic split) within common carp Cyprinus carpio between the native wild form found in Lake Biwa and the Eurasian wild form, along with domesticated varieties. This supports the idea of the ancient origin of the native Japanese form (Cyprinus sp.), as well as the East Asian ancient lineage of wild common carp (C. carpio) previously proposed on the basis of fossil data. However, it is unknown when the carp from the continent was introduced to Japan. In addition, a possible multiple origin of koi carp was indicated by the polyphyletic distribution of five mtDNA haplotypes of koi carp within the ‘Eurasian’ clade. Moreover, the oldest record of the introduction of non-native fish in Japan is that of goldfish from China (1502 or 1602), and there is no record of carp (including colored carp) until the introduction of the mirror carp, called Doitsugoi (German carp), in 1904.