CHAPTER SEVEN 

 PATHOLOGY OF BURENELLA DIMORPHA INFECTION 



Very few protozoan diseases of insects may be diagnosed 

 by simple observation of pathognomonic signs. Pebrine (infec- 

 tion of the silkworm, Bombyx mori L. , by the microsporidium 

 Nosema bombycis Naegeli) provides a classic example of patho- 

 gnomonic signs in insects , being characterized by the appear- 

 ance of dark, pepper-like spots on the integijment. Infection 

 of the tropical fire ant, Solenopsi s geminata (Fabricius), 

 by the neogregarine Mattesia geminata Jouvenaz and Anthony 

 (197 9), may be readily diagnosed by eye teratology and a 

 pattern of abnormal melanization in pupae beginning with 

 a "sooty" black discoloration of the legs. In the same 

 host, infection by Burenella dimorpha Jouvenaz and Hazard 

 is manifested by signs of a type that appears to be unique 

 in insects. In general, however, specific manifestations 

 of protozoan infections, if present at all, are related 

 to particular tissues and may be detected only by histolog- 

 ical examination (Brooks, 1974). 



Insects infected by protozoa may exhibit nonspecific 

 signs such as loss of appetite, diarrhea, sluggishness, 

 irregular growth, stunted or malformed adults, reduced fecun- 

 dity, and premature death of immatures or adults. Often, 



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