Asian Misgurnus anguillicaudatus (scientific name: Synbranchidae family, representative species such as eel Monopterus albus) is a kind of freshwater benthic fish distributed in tropical and subtropical regions of Asia. It has the ability to highly adapt to hypoxic environment and is often called "rice field fish" or "swamp eel". It belongs to the family Gracilidae, containing about 15 genera and more than 100 species, mainly distributed in the freshwater basins of East Asia, Southeast Asia and South Asia. Widely distributed in the Yangtze River, the Pearl River Basin in China, the Mekong River, the Irrawaddy River in Southeast Asia and the rice fields, swamps, rivers and ponds in the Ganges Plain of India.

The scientific name of the Japanese striped loach is Cobitis biwae, which is a native fish species in Japan. Found in sandy and gravelly substrates in rivers. This species is a native species of this state. However, it was not found in Yamaguchi Prefecture. It is considered an invasive species in Lake Chuzenji and eastern Shizuoka Prefecture. Because they are small and easy to raise, they are also farmed as ornamental fish.