JOHNSON: PARASITES OF BENTHIC AMPHIPODS 



dinids (Table 1). The organisms occupied the 

 hemocoel and morphologically were most like Hema- 

 todinium perezi Chatton and Poisson, which was 

 described from European portunid crabs. There 

 were two distinct types, based on morphology and 

 development. There is not enough information about 

 the life history stages of Hematodinium to warrant 

 assigning either or both types to that genus, and 

 they are identified casually in this paper as "Type 

 A A" and "Type AV" (Table 2). The Type AA forms 



were similar in all the amphipod species they in- 

 fected, but there was variation in forms assigned 

 to Type AV, and probably more than one species was 

 involved. 



Host and Geographic Distribution 



Juvenile and mature amphipods of both sexes 

 were attacked. Only Type AA was found in Am- 

 pelisca agassizi (Judd), Byblis serrata Smith, and 



Table 1 .—Amphipod species infected with Type AA and Type AV parasites. 



Species of amphipod 



Type of 

 parasite 



Prevalence 



positive stations 



(%) 



Prevalence 



all stations 



(%) 



Ampelisca agassizi (Judd) 

 Byblis serrata Smith 

 Harpinia propinqua Sars 

 Ampelisca vadorum Mills 

 Ampelisca verrilli Mills 

 Casco bigelowi (Blake) 

 Leptocheirus pinguis (Stimpson) 

 Melita dentata (Kr0yer) s. lat. 

 Monoculodes edwardsi Holmes 

 Protohaustohus wigleyi Bousfield 

 Phoxocephalus holbolli Krflyer 

 Rhepoxynius epistomus 



(Shoemaker) 

 Unciola species (probably all 



U. irrorata Say and U. inermis 



Shoemaker) 



1 Parasites in two of the infections may not be either Type AA or Type AV. 



Table 2. — Main characteristics of Type AA and Type AV. 



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