Hyptiasmus Kossack, 1911

(Members of this genus have a prepharyngeal genital pore and the vitelline fields are confluent posteriorly) (Tables 16–17)

Diagnosis. Cyclocoelidae; Hyptiasminae. Body, lanceolate to linguiform, sometimes tapered anteriorly. Rudimentary oral sucker often present; rudimentary ventral sucker present in some species. Genital pore prepharyngeal. Ovary intertesticular nearly in line with tandem or nearly tandem testes near posterior arch of cyclocoel. Uterine coils typically overreaching ceca laterally, often invading posttesticular space. Vitelline fields confluent posteriorly. Typically prasites in body cavity, air sacs and lungs of anseriform ( Anatidae) and gruiform ( Rallidae) birds but H. magniproles Witenberg, 1928 was reported from Himantopus himantopus ( Charadriiformes: Recurvirostridae).