Heterophyidae
Heterophyidae is a family of intestinal trematodes in the order Plagiorchiida. Description: "Tegument covered by spines. Oral sucker not armed or armed by cyrcumoral spines. Pharynx presented. Genital synus presented. Ventral and genital suckers usually not combined. Cirrus and bursa absent. Two testes located in posterior part of the body. Vitellaria in posterior part of the body." First intermediate hosts are molluscs of Prosobranchia, second intermediate hosts are fishes. Definite hosts are birds and mammals, including humans.