Prosorhynchus Odhner, 1905 (Digenea: Bucephalidae) from the orange-spotted grouper Epinephelus coioides (Hamilton, 1822) (Epinephelidae), including Prosorhynchus tonkinensis n. sp., from the Gulf of Tonkin, Vietnam.

A total of 169 specimens of the orange-spotted grouper Epinephelus coioides (Hamilton) were collected from fishermen and marine fish farms in the Gulf of Tonkin, Vietnam. Five different species of Prosorhynchus Odhner, 1905 were recorded, including P. tonkinensis n.