Reproductive cycle of Triplophysa stenura (Herzenstein, 1888) (Balitoridae: Nemacheilinae) from the Yarlung Tsangpo River in the Tibetan Plateau, China.

The reproductive biology of Triplophysa stenura, an indigenous cyprinid species from the Qushui County in the middle of the Yarlung Tsangpo River in the Tibetan Plateau, China, was investigated by bimonthly sampling from May 2014 to April 2015 using electrofishing. The gonadosomatic index ( GSI) of T. stenura differed significantly between males and females over the seasonal trend, indicating that spawning extends from March (shortly after the ice melts) to May, as observed for indigenous species in response to environmental conditions on the cold plateau. Average oocyte diameter was 0.66 ± 0.13 mm, whereby the oocyte diameter distribution exhibited a clear seasonal pattern as the temporal pattern of GSI. Absolute fecundity of T. stenura was 3999 eggs/individual, which increased significantly with the increase in fish size and gonad weight, demonstrating the relationship of an exponential equation between them. [ABSTRACT FROM AUTHOR]