DNA barcoding of Schizothoracinae fishes from the Yarlung Zangbo River in Tibet

Abstract

The nine endemic species of the genus Schizothorax from the Yarlung Zangbo River, Tibet comprise a putative cyprinid species flock. In this study, the effectiveness of the COI DNA barcode for Schizothoracinae species identification was verified by using 45 COI sequences covering nine species in four genera of Schizothoracinae fishes. The average Kimura two parameter (K2P) genetic distances within and among species were 0.13% and 8.57%, respectively. The results revealed that most of the species were clearly discriminated by their estimated genetic distances and monophyletic clustering in a maximum likelihood tree. However, insignificant genetic distances were noticed in two reportedly valid species: Schizothorax molesworthi and S. integrilabiatus (0.1%), and the monophyly of S. macropogon could not be recovered in the schizothoracine group. The fishes of S.curilabiatus living in the lower course of Yalung Zangbo River were clustered together with three species from the upper course, which is inconsistent with the geographical distribution of the populations.

Keywords:

• COI
• DNA barcoding
• schizothoracine
• yarlung zangbo river

Acknowledgements

The authors would like to thank Shuaijie Sun for the assistance in sample collection and identification.

Disclosure statement

The authors alone are responsible for the content and writing of the paper. The authors report no conflicts of interest.

Data availability statement

The data that support the findings of this study are openly available in GenBank of NCBI at https://www.ncbi.nlm.nih.gov, with reference number: MN916720-MN916724 for Schizothorax oconnori; MN928472-MN928476 for Schizothorax waltoni; MN928467-MN928471 for Schizothorax macropogon; MN928384-MN928388 for Schizopygopsis younghusbandi; MN928379-MN928383 for Oxygymnocypris stewartii; MN928462-MN928466 for Ptychobarbus dipogon; MN928986-MN928990 for Schizothorax curilabiatus; MN931252-MN931256 for Schizothorax molesworthi; MN928477-MN928481 for Schizothorax integrilabiatus.

Additional information

Funding

This study was funded by the Tibet science and technology projects [XZ-2019-NK-NS-004].