Two new species of Maritrema (Trematoda: Microphallidae) from the Pacific Coast of North America

Abstract

Maritrema pacifica n. sp. has an incomplete posterior ring of vitellaria, a spiny cirrus, a trilobed ovary, and a well-differentiated metraterm. It differs from M. patulus Coil, 1955 in the larger body, longer esophagus, round rather than slit-like genital pore, and larger eggs. It differs from M. interrupta Oshmarin, 1970, M. eroliae Yamaguti, 1939, and M. kitanensis Shibue, 1953 in the smaller cirrus sac containing sparse prostate cells. M. pacifica has the following definitive hosts: Larus californicus Lawrence, L. occidentalis Audubon, Turdus migratorius L. from Oregon, and Crocethia alba (Pallas) from British Columbia. The metacercariae, from Orchestoidea corniculata from California, became ovigerous in Locke's solution at 39 °C.Maritrema paracadiae n. sp. (synonym M. acadiae of Deblock and Rausch (1972)) differed from the type specimens of M. acadiae (Swales, 1933) in the proportionately larger oral and ventral suckers; the larger, inverted J-shaped cirrus sac containing prominent prostate cells; and the distribution of the uterus within, instead of overlapping, the posterior vitellarian ring. M. paracadiae was found in the intestine of Bucephala islandica (Gmelin) from Washington.