48 TREMATODES OF THE PACIFIC NORTHWEST 



Ophioxenos dienteros Sumwalt, 1926 



Hosts : Bufo boreas Wash. Sumwalt, 1926 



Thamnophis sirtalis Wash. Sumwalt, 1926 



Thamnophis ordinoides Wash. Sumwalt, 1926 



Clcininys marmorata Ore. Thatcher, 1954 



This parasite has not been reported outside of the Pacific Northwest. 



Morphology: Described and figured bj' Skrjabin (1949). 



Paramphistomum cervi (Schrank, 1790) Fischoeder, 1901 



Synonyms: Fasciola cervi Schrank, 1790 

 Festucaria cervi Zeder, 1790 

 Fasciola elapJii Gmelin, 1791 

 Monostoma conicum Zeder, 1800 

 Amphistoma conicum Rudolphi, 1809 

 Aniphistoma cervi Stiles and Hassell, 1900 

 Cercaria pigmeniata Sonsino, 1892 



S3'nonymy after Skrjabin (1949). 



Host: Cattle B.C. Swales, 1933 



Other North American hosts were recorded by Cram (1925), Krull (1933a), 

 Price (1928), and Price and Mcintosh (1944). 



Taxonomy: Morgan and Hawkins (1949) thought that the taxonomy of this 

 genus needed revision. Dawes (1946) included a great manj' more species 

 as synonyms of P. cervi. 



Morpholog>': This form was figured by Morgan and Hawkins (1949) and de- 

 scribed and figured by Skrjabin (1949). 



Biology: Cercaria pigmentata Sonsino, 1892, develops in various species of 

 Physa and BuUinus, encysts readily, and is ultimate!}^ eaten bv the definitive 

 host. (Szidat, 1936; Looss, 1896; Takahashi, 1927;' Brumpt, 1936; Balozet 

 and Callot, 1938; and Dinnik, 1951.) 



Paramphistomum sp. 



Several amphistomes have been reported from the Pacific Northwest which 

 cannot be placed in a species with certainty. Bruce (1930) reported Amphisto- 

 nium conicum from cattle of British Columbia, and one cannot be certain whether 

 this was really P. cervi or P. microbothrium Fischoeder 1901, since A. conicum 

 was not adequately defined. Dikmans (1945) reported Paramphistomum sp. from 

 cattle from British Columbia and Oregon. 



Stichorchis subtriquetrus (Rudolphi, 1814) Liihe, 1909 



Sj'nonyms : Amphistoma subtriquctriun Rudolphi, 1814 

 Distoma amphistomatoides Bojanus, 1817 

 A})iphisto))iu})i subtriquetrus Westrumb, 1823 

 Cladorchis (Stichorchis) subtriquetrus Fischoeder, 1901 



