Cladotaenia circi is a tapeworm of the genus Cladotaenia that has birds of prey as its definitive host, such as the western marsh harrier (Circus aeruginosus), hen harrier (Circus cyaeneus), and peregrine falcon (Falco peregrinus) in Europe. It has been found at low frequences in small mammals, such as the bank vole (Myodes glareolus) and common vole (Microtus arvalis) in Hungary and the marsh rice rat (Oryzomys palustris) in Florida.