DNA Barcoding Analysis Of Partial Species Of Cyprinid (Barbinae And Labeoninae) In China

Cyprinidae(Osteichthyes,Actinopterygii,Cypriniformes,Cyprinoidei)is widely distributed in Eurasia,East Indies,Japan,Africa and North America,and supports a larger freshwater capture and aquacultural fishery,with considerable economical and ecological values.In recent years,because of the negative environmental changes and overfishing,Cyprinid are facing the cascading consequences of percocity,individual miniaturization and the reduction of population size,demanding for urgent measures to be taken for better management and sustainable exploitation.Although correct identification of species is essential to the management of fishery,the insufficient morphological diagnostic characters cause much misidentification in the 2representative subfamilies of Cyprinidae in south China: Barbinae and Labeoninae.To discuss the taxonomic status of these fishes,in present study,the partial mitochondrial cytochrome C oxidase subunit I gene(COI)of 377 specimens from 46 species and 27 sequences from 8 species downloaded from Genbank were combined to conduct DNA barcoding analysis.The results are as following:DNA barcodes of Barbinae were grouped into 31 distinct clades,and the average genetic distance among clades(14.20%)is approximately 28.40-fold of the average genetic distance within clade(0.5%),of which Acrossocheilus beijiangensis,Acrossocheilus parallens,Acrossocheilus cinctus,Acrossocheilus fasciatus,Acrossocheilus wenchowensis,Acrossocheilus jishouensis,Onychostoma gerlachi,Onychostoma lepturum,Onychostoma simaum,Onychostoma alticorpus,Onychostoma ovali,Acrossocheilus yunnanensis,Spinibarbus sinensis,Spinibarbus yunnanensis,Spinibarbus denticulatus,Percocypris pingi,Scaphiodonichthys acanthopterus,Sinocyclocheilus grahami,Spinibarbus caldwelli,Spinibarbus hollandi,Barbodes vernayi,Mystacoleucus lepturus,Mystacoleucus marginatus,Puntius sophore,Tor sinensis,Puntius ticto and Puntius snyderi formed monophyletic clades respectively,conforming their species status.The others were mixed into 4clades,of which Acrossocheilus longipinnis and Acrossocheilus iridescens were synonyms,Acrossocheilus elongatus and Onychostoma elongatum were synonymstoo,Poropuntius opisthopterus downloaded from Genbank and Poropuntius huangchuchieni might be the same species or different species,Genbank-downloaded PunpauYunN1 might belong to Puntius semifasciolatus.The genetic distance(5.47%)between two subclades of Tor sinensis revealed cryptic diversityDNA barcodes of labeoninae were grouped into 18 distinct mitochondrial clades,and the average genetic distance among clades(12.29%)is approximately 42.38-fold of the average genetic distance within clade(0.29%),of which Ptychidio jordani,Semilabeo prochilus,Semilabeo notabilis,Rectoris posehensis,Pseudocrossocheilus bamaensis,Discogobio bismargaritus,Discogobio macrophysallidos,Discogobio yunnanensis,Bangana tungting,Sinilabeo rendahl,Osteochilus salsburyi,Cirrhinus molitorella,Garra fasciacauda,Garra salweenica,Placocheilus cryptonemus and Garra orientalis formed monophyletic clades respectively,conforming their species status.Garra imberba and Garra pingi pingi were mixed in the same clades,indicating that they might be the same species.In conclusion,additional nuclear markers and more specimens should be study to those species mixed in the same clade to rule out the potential possibility of hybridization.As conservative morphological characters of some species of Barbinae and Labeoninae may result in misidentification,DNA barcoding based on the mitochondrial COI gene sequences could improve the accuracy of species identification.