Coexistence of Three Divergent mtDNA Lineages in Northeast Asia Provides New Insights into Phylogeography of Goldfish (Carssius auratus)

Abstract

Goldfish (Carassius aurautus), which is a middle size cyprinid, widely distribute throughout Eurasia. Phylogeographic studies using mtDNA markers have revealed several divergent lineages within goldfish. In this study, mtDNA variations were determined to elucidate the phylogeographical pattern and genetic structure of goldfish in Northeast Asia. A total of 1054 individuals from Amur river basin were analyzed, which including five newly collected populations and four previously reported populations. Three distinct mtDNA lineages were identified in those samples, two of which corresponded to two known lineages C2 and C6, respectively. The third lineage referred to as C7, following six known lineages of goldfish in mainland Eurasia. AMOVA results suggested that most of the genetic variations were among lineages, rather than among populations or twice samplings. We noted that the control region (CR) and cytochrome b (cytb) sequences of lineage C7 have been reported in previous studies, respectively. However, the evolutionary position and distribution pattern of this lineage was not discussed in the context of the species. Our results showed that “odd” CR and “hidden” cytb sequences from Central Asia represent the same mtDNA lineage of goldfish. The known samples of C7 lineage were collected from Central Asia (Eastern Kazakhstan and Western Mongolia) to East Asia (Northeast China and Far East Russia), which suggested that it had a wider distribution, rather than limit in Central Asia.

A Fish of Multiple Faces, Which Show Us Enigmatic and Incredible Phenomena in Nature: Biology and Cytogenetics of the Genus Carassius

“…Without the use of modern molecular techniques, some authors have previously classified C. carassius as Japanese Funa or “Black-Funa” (sensu [ 6 ]), and an ancestor of goldfish [ 6 , 7 , 8 ]. However, these classifications are incorrect, based on previous phylogeographical studies that show C. carassius (sensu Linnaeus, 1758) as being native to many European freshwaters, with no records of occurrence in Japan [ 3 , 9 , 10 , 11 ]. Carassius cuvieri is phylogenetically distinct from C. carassius and all other Carassius species, representing a basal diverged clade [ 12 , 13 ] with morphological differences that do not correspond with levels of genetic differentiation [ 14 ].…”

A Fish of Multiple Faces, which Show us Enigmatic and Incredible Phenomena in Nature: Biology and Cytogenetics of the Genus Carassius

“…Without the use of modern molecular techniques, some authors have previously classified C. carassius as Japanese Funa or Black-Funa [sensu 7] , and an ancestor of goldfish [7][8][9]. However, these classifications are incorrect, based on previous phylogeographical studies which show C. carassius (sensu Linnaeus, 1758) as being native to many European freshwaters, with no records of occurrence in Japan [3,[10][11][12]. Carassius cuvieri is phylogenetically distinct from C. carassius and all other Carassius species, representing a basal diverged clade [13,14] with morphological differences which do not correspond with levels of genetic differentiation [15].…”