DIGENETIC TREMATODES 25 



Neascus sp. 



N^casais is a "generic" name for metacercariae of diplostomid trematodes 

 for which the adult form is unknown, is encysted, and lacks lateral suckers. 

 Bangham and Adams (1954) reported the following species of fresh water fish 

 as hosts of Neascus in British Columbia : 



Sahno clarkii Salvelinus fontinalis 



Salvelinus malma Catostomus catostomus 



Catostomus macrocheiltis Mylocheilus caiirintim 



Acrocheilus alutaceum Coiiesiiis pliimheus 



Rhinichtliys cataractae Ptychocheilus oregonensis 



Richardsonius balteatiis Micropteriis salmoides 

 Lepomis gibbosiis 



Pharyngostomoides procyonis Harkema, 1942 



Host : Procyon lotor Ore. *Location unknown 



The onl}' other records are those of Harkema (1942). 



Posthodiplostomum minimum (MacCallum, 1921) Dubois, 1936 



Synonyms: Diplostonnim minimum MacCallum, 1921 



Neodiplostomum minimum (MacCallum, 1921) Dubois, 1935 

 Neodiplostomum orchilongum Noble, 1936 

 Posthodiplostomum orcliilongum (Noble, 1936) Dubois, 1937 



Hosts: Bangham and Adams (1954) reported the following fresh water fish 

 from British Columbia as hosts for the larval stages of this trematode : 



Catostomus catostomus Catostomus macrocheilus 



Mylocheilus caurinum Acrocheilus alutaceum 



Couesius plumbeus Rhinichthys cataractae 



Ptychocheilus oregonensis Richardsonius balteatus 



Gasterostcus aculeatiis Lota lota 



Lepomis gibbosus Cottus aspcr 



Moi^e hosts from the Pacific Northwest with larval forms include : 

 Catostomus columbianus palouscanus W^ash. Griffith, 1953 

 Catostomus macrocheilus Wash. Griffith, 1953 



Lepomis macrochirus Wash. Griffith, 1953 



Additional hosts have been listed by Dubois (1938), Hoffman (1958). 



Morphology: Described and figured by Dubois (1938). 



Biology: Miller (1954) showed oculate furcocercous cercariae to develop in 

 Physa hetcrostropha, encyst experimentally in Lepomis gibbosus and L. 

 megalotus, and develop in chicks. Hoffman (1958) has done additional work- 

 on their life history and physiology. He listed an extensive bibliography. 



•■ Asterisks denote new (previously unpublished) reports of the par.'isite in the area. 



