The order consists of two suborders, Dactylogyrinea 

 Bychowsky, and Monopisthocotylinea (Odhner) Bychowsky. 



1. Suborder Dactylogyrinea Bychowsky, 1937 



Gyrodactyloidea Johnston and Tiegs, 1922 , part . 



Dactylogyridea, having larvae with 12 to 14 edge hooks. The 

 adult forms with attaching discs consisting of the same number of edge 

 hooks, 1-2 pairs of middle hooks which can be absent secondarily, and 

 of a more or less complex connecting apparatus between the middle 

 hooks. Often>on and above the disc are supplementary chitinous hook- 

 shaped fornaations which serve as the basic armature for the attach- p. 346 

 ment of the worms to the body of the host. The digestive system has 

 two intestinal trunks merging at the end or ending blindly. In rare cases 

 the intestinal trunks form lateral outgrowths. 



Parasites of noarine and fresh water Teleostei 



The suborder includes three families --Dactylogyridae 

 Bychowsky, Diplectanidae Bychowsky, fam. nov. , and Protogyro- 

 dactylidae Johnston and Tiegs. In addition to that, Calceostomatidae 

 (Parona and Perugia) Price are placed here conditionally. 



1. Family Dactylogyridae Bychowsky, 1933 



Gyrodactylidae Cobbold, 1877, part . ; Calceostomatidae 

 (Parona and Perugia, 1890) Price 1937, part. 



Dactylogyrinea, having relatively small or medium sizes in 

 the adult state. ^ The attaching apparatus consists of the chitinous 

 armature including 14 edge hooks, and 1-2 pairs of middle hooks 



_ _ 



Here and later by small sizes is understood the length of worms up 

 to one millimeter, by medium — up to 2 - 5 millimeters and by large - 

 above 5 millimeters. 



which can be secondarily absent. The chitinous connecting plates which 

 unite the hooks into a single system and located between the middle hooks. 

 In rare cases the connecting formations are absent. Often there are 



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