为鲈形目，斗鱼科，斗鱼属的鱼类。分布在中国(珠江北至黑龙江)，日本(中部和南部，但可能为引入种)，韩国与俄国(黑龙江，但可能为引入种)，一般生活于江河支干流。圆尾斗鱼为小型鱼类，体长不超过13cm，栖息于湖泊、池塘、沟渠、稻田等静水环境中，以挠足类、轮虫、水生昆虫为食。
学名：Macropodus ocellatus
英文名：Round tail fish
This species belongs to the family of Belontiidae,order of perciformes.Distributed in China, Japan, Korea and Russia,generally living in rivers and tributaries.Round tail fish is a kind of small fish, which the body length is not more than 13cm, and it inhabits in the lake, ponds, rice fields and other hydrostatic environment.It mainly lives on rotifer, aquatic insects.