Native to central and southern China and northern Vietnam.
In China the Yangtze River appears to represent the northern limit of its range, and to the south it’s also present on Hainan Island and Hong Kong.
It’s also been introduced to Taiwan and Ishigaki Shima Island in the Ryukyu Islands, Japan.
Records from Vietnam pertain only to the Red (also known as the Sông Cái or Yuan) River.
Type locality is given simply as ‘Asia’.
Size 20cm+