Oryzias

Oryzias is a genus of ricefishes native to fresh and brackish water in east and south Asia. Some species are widespread and the Japanese rice fish (O. latipes) is commonly used in science as a model organism, while others have very small ranges and are threatened. They are small, up to 8 cm (3.1 in) long, and most are relatively plain in colour. The genus name Oryzias is a reference to the scientific name for rice, Oryza. They have an unusual reproductive behavior where the female facultatively carries the eggs in a cluster at the pelvic or anal fins for a period after they have been fertilized. There are currently 33 recognized species in this genus: