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A BIOLOGY OF CRUSTACEA 



PARASITIC AMPHIPODS 



It only takes a glance at a whale louse to realise that it is adapted 

 to clinging. The limbs are strongly hooked, and the body is 

 flattened. Unfortunately very little is known of the biology of these 

 creatures. There are five genera, and of these four have only one 

 species each. The number in the main genus, Cyamus, is uncertain, 

 but not high. The various species have been found on and in the 

 skins of whales from various parts of the world. 



Apart from the whale lice there is a notable lack of parasites 

 among the amphipods, though it is likely that some of the forms 

 with modified mouthparts, such as Trischizostoma, are parasites on 

 fish. 



Fig. 54. Cyamus boopis (Amphipoda). 



Ventral view of a specimen from a 



humpback whale (Megaptera nodosa). 



Actual length about 12 mm. 



