Studies on the Helminth Fauna of Alaska. XL. Strigea gruis sp. n., a Trematode Parasite of Grus canadensis (L.)

Abstract

Strigea gruis sp. n. (Trematoda: Strigeata, Strigeidae) is described from the sandhill crane Grus c. canadensis (L.). Only one other species of Strigea (S. neotidis Bisseru, 1956) is known from birds of the order Gruiformes; it is distinguished from S. gruis by several characteristics including its slender form, campanulate anterior segment, size of pharynx and of eggs, position of ovary, and position and size of testes. S. gruis differs from two other species having a relatively large pharynx, S. sphaerula (Rudolphi, 1803) and S. intermedia Szidat, 1932, both parasites of corvids, in the form of the anterior segment and in details of the genital organs. During the period 1955 to 1963, 13 specimens of sandhill crane, Grus c. canadensis (Linnaeus), were collected in Alaska by personnel of the Zoonotic Disease Section, Arctic Health Research Center, and examined for helminths. An undescribed species of trematode belonging to the family Strigeidae Railliet, 1919, of the suborder Strigeata La Rue, 1926, was found in three birds. The infected hosts were collected as follows: (No. 24638) 15 July 1960 at Goose Bay, Cook Inlet; (No. 26336: type material) 18 May 1961 at Potter Marsh, about 10 miles south of Anchorage; (No. 29436) 16 June 1963 at Potter Marsh. The birds, all adults, had 7, 80, and 5 of these strigeids, respectively. Strigea gruis sp. n. (Figs. 1 and 2) (All measurements in millimeters)