''Oryzias curvinotus'' or the Hainan medaka is a species of

ricefish The ricefishes are a family (Adrianichthyidae) of small ray-finned fish that are found in fresh and brackish waters from India to Japan and out into the Malay Archipelago, most notably Sulawesi (where the Lake Poso and Lore Lindu species are kn ...

which is found in Quang Ninh Province in northern Vietnam and

Hainan Hainan (, ; ) is the smallest and southernmost province of the People's Republic of China (PRC), consisting of various islands in the South China Sea. , the largest and most populous island in China,The island of Taiwan, which is slightly l ...

Guangdong Guangdong (, ), alternatively romanized as Canton or Kwangtung, is a coastal province in South China on the north shore of the South China Sea. The capital of the province is Guangzhou. With a population of 126.01 million (as of 2020) ...

and

Hong Kong Hong Kong ( (US) or (UK); , ), officially the Hong Kong Special Administrative Region of the People's Republic of China (abbr. Hong Kong SAR or HKSAR), is a city and special administrative region of China on the eastern Pearl River Delta i ...

in southern China. It is found in both fresh and brackish water. This species was described as ''Aplocheilus curvinotus'' in 1927 by J.T. Nichols and C.H. Pope with the type locality given as Nodoa, Hainan Island, China.

References

Oryzias Taxa named by John Treadwell Nichols Taxa named by Clifford H. Pope Fish described in 1927 {{Beloniformes-stub