Microphallus pseudopygmaeus chemically castrates (parasitic castration) its host, the snail Onoba aculeus, and causes it to grow larger than normal (it is not clear if this gigantism benefits the host or parasite or if it is a non-adaptive side-effect).
For example, Microphallus pseudopygmaeus chemically castrates its host, the snail Onoba aculeus, and causes it to grow larger than normal.