C. pseudomicrostomum Harrah, 1922

Type host. “ Wild duck” ( Anseriformes: Anatidae); type host species unknown.

Type locality. Omaha, Nebraska, USA.

Additional hosts. American coot, Fulica americana Gmelin ( Gruiformes: Rallidae)— Harrah (1922). Species of Anas Linnaeus, Capella Frenzel, Fulica Linnaeus and Totanus Bechstein—Yamaguti (1971) .

Additional localities. Europe, Mexico, People’s Republic of China—Yamaguti (1971).

Previously proposed synonyms. Cyclocoelum (Antepharyngeum) pseudomicrostomum (Harrah, 1922) — Witenberg (1926); Cyclocoelum (Cyclocoelum) pseudomicrostomum (Harrah, 1922) — Bashkirova (1950); C. mycrocotyleum Noble, 1933 — Bashkirova (1950); C. mutabile (Zeder, 1800) — Joyeux & Baer (1927); C. microstomum (Creplin, 1829) — Ingersoll (1955).

Remarks. In this species the mouth is surrounded by an “external banding musculature” that likely represents a rudimentary oral sucker—Harrah (1922); Bashkirova (1950).