The sterlet
lives in the affluents of the Black and Caspian Seas, and grows up to 50 cm in length. It likes deep lowland waters, and feeds on larvae and insects.
The interesting fact about the clown fish is that all individuals are born male, then the largest fish in the group changes sex and becomes the dominant female, whilst the next largest assumes the role of dominant male. Individuals of this species can reach a maximum length of eight centimetres. Clown fish females can be two or three times larger than the males.