Abstract
Three trematodes from the digestive tract of two harlequin ducks, Histrionicus histrionicus pacificus, were collected at Friday Harbour, Washington. They are Paramonostomum histrionici, n. sp. (Notocotylidae), and two microphallids, Pseudospelotrema japonicum Yamaguti, 1939 (new locality record) and Spelotrema pygmaeum (Levinsen, 1881) Jagerskiold, 1901 (new host and locality record).