DIGENETIC TREMATODES 39 



Opechona parvasoma Ching, 1960 



Host: Sebastodes melanops Wash. Ching, 1960b 



Lepidapedon pugetensis Acena, 1947 



Host: Sebastodes nebulosiis Wash. Acena, 1947 



Other records are unknown. Lebour (1908) found larval stages of L. rachion 

 in Cardium edule but other knowledge of life histories in the genus is wanting. 

 Hanson (1950) questioned the validity of the species. It was poorly described, 

 and the types were not available. 



Lepidapedon calli Acena, 1947 



Host : Parophrys vetulus Wash. Acena, 1947 



Other records are unknown. Hanson (1950) stated that this cannot be a 

 species of Lepidapedon, but she offered no suggestions as to the proper disposi- 

 tion of the species. See note on life history under L. pugetensis. 



Lepidapedon microcotyleum (Odhner, mss.) Dollfus, 1953 



Host: Theragra chalcogramma Wash. Ching, 1960b 



Family LISSORCHIDAE 



Triganodistomum attenuatum Mueller and Van Cleave, 1932 



Hosts: Catostomus catostomus B.C. Bangham & Adams, 1954 



Catostomus macrocheihis B.C. Bangham & Adams, 1954 



Additional record from New York (Mueller and Van Cleave, 1932). Wal- 

 lace (1939, 1941) found T. mutabile to have tailless cercariae; it develops in 

 species of Helisoma and encysts in Chaetogaster or Planaria, but nothing is 

 known of the life history of T. attemiatum. 



LissoTchis sp. 



Shaw (1947) reported Lissorchis from an unnamed host from Oregon. 



Family MICROPHALLIDAE 



Gymnophallus deliciosus (Olsson, 1893) Odhner, 1900 



Synonym : Distoma dcUciosum Olsson, 1893 



Host: Larus occidentalis Ore. Reish, 1950 



Hosts from Europe have been reported by Olsson (1893) and Timon-David 

 (1955). 



Taxonomy : The genus Gymnophallus was placed in Gymnophallidae by Morosov 

 (1955) and in the Fellodistomatidae by Cable (1953). It probably does not 

 belong in the Microphallidae, but its placement is still undecided. 



Morphology: It is described and figured by both Dawes (1946) and Morosov 

 (1955). The life history of this species has not been worked out, but other 

 species of the genus are known. See Giard (1907), Jameson (1902), Hutton 

 (1952), and Zelikman (1953). For additional bibliography see Yamaguti 

 (1958). 



