Polijonchoinea 



Oltgonctioined 



Fig. 264. The diagram of occurrence of monogenetic trematodes on the basic 

 groups of their hosts. Inverted triangles indicate families primarily parasitizing 

 the given group of hosts, upright triangles --secondarily adapted. Relative width 

 of the base of the triangles shows approximately the volume (number of genera) 

 of the family. The Roman numerals--orders, whereas the Arabics represent 

 families of monogenetic trematodes. I--Dactylogyridea; II--Tetraonchidea; 

 III--Gyrodactylidea; IV--Diclybothriidea; V--Chimaericolidea; VI--Mazocraeidea. 

 l--Dactylogyridae; 2--Diplectanidae; 3--Protogyrodactylidae; 4--Calceostomatida< 

 5--Monocotylidae; 6--Acanthocotylidae; 7--Dionchidae; 8--Capsalidae; 

 9__Loimoidae; 10--Tetraonchidae; 1 1 --Amphibdellatidae; 12--Tetraonchoididae; 

 13--Bothitrematidae; 14--Gyrodactylidae; 15--Polystomatidae; 16--Sphyranuridae; 

 17--Diclybothriidae; 18--Hexabothriidae; 19--Chimaericolidae; 20--Mazocraeidae; 

 21--Hexostomidae; 22--Anthocotylidae; 23--Discocotylidae; 24--Plectanocotylidae; 

 25--Diclidophoridae} 26--Microcotylidae; 27--Protomicrocotylidae; 

 28--Gastrocotylidae. 



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