Monogeneans are a gathering of ectoparasitic flatworms regularly found on the skin, gills, or balances of fish. Grown-ups are bisexuals, which means they have both male and female conceptive structures. Some monogeneans are oviparous and some are viviparous. Oviparous assortments discharge eggs into the water. Viviparous assortments discharge hatchlings, which promptly join to another host. The sort Gyrodactylus is a case of a viviparous assortment, while the class Dactylogyrus is a case of an oviparous assortment. Freshwater fish that become contaminated with this parasite become torpid and wind up swimming towards the outside of the water. Moreover, some might be seen scouring the base or sides of their skin where the parasite is found.