A review on the morphology, biology, reproduction and breeding of Polypterus fish

Ornamental fish is one of the most important industries in the aquaculture industry, which has international reputation compared to other aquatics. Breeding of ornamental fish has been successful in terms of using internal resources, high profitability, low investment, relative simplicity of production technology, and the possibility of spreading innovation and participation of young people for direct and indirect employment generation. Polypterus fish which is known as Azarakhsh fish in Iran, is one of our prehistoric fish whose history goes back to more than 200 million years ago. In addition to water breathing, this fish has air breathing and is resistant to many diseases and unfavorable environmental conditions. The birthplace of this fish is Africa and the catchment areas of the Nile River, Senegal, Niger, and other countries. The weight of this fish is reported to be about two hundred grams. In nature, these fish use insects, small fish, crustaceans, frog larvae and some molluscs, although some polypterous species are insectivorous and their lifespan reaches 34 years. Although it is very difficult to reproduce polypterus fish inside the aquarium, it can be done using techniques. The best age for polypterus fish reproduction is over 7 years and 30 cm long, otherwise these fish will not spawn. In order to stimulate the spawning of these fishes, it is necessary that the place of the aquarium is quite large and covered with hiding places.