AMBLYOMMA 



INTRCDUCTION 



Of about a hundred Amblyomma species in the world, some twenty 

 occ\rr In Africa and eight in the Sudan, The specific identity of 

 most common African species appears to be settled and only in ex- 

 ceptional instances are specimens likely to be confused. One of 

 the chief remaining taxonomic problems among common African amblyom- 

 mas is the A, marmoreum group, in which the range of species varia- 

 tion needs to be determined for several somewhat differing forms. 

 Observations from the present study indicate need for further re- 

 search on the relationship between A, variegatum and A. pomposum 

 and suggest that the latter may be no more than a sub"species of 

 the former. Recently a few workers have designated certain African 

 populations by subspecific ranks that challenge further investiga- 

 tion. Several West African species are known from so few specimens 

 that their validity is questionable. 



This genus has been the subject of an extensive review by 

 Robinson (1926) comprising volume four of Nuttall's Monograph 

 on Ticks, The African species have been keyed by Rageau and Ver- 

 vent (1953), 



The immature stages of most African amblyomraas remain to be 

 described with satisfactory criteria for distinguishing them. 



Economically, two African species have thus far been shown 

 to harbor or transmit human disease organisms. A, hebraeum is 

 considered an important boutonneuse fever ("'tick"~typhus"'J vector 

 in South Africa and A, variegatum has been found naturally in- 

 fected with Q; fever in French Equatorial Africa near the Sudan 

 border. Several species are important transmitters of veterinary 

 diseases, cause damage to animal skins, or debilitate animals 

 through the volume of blood withdrawn or by initiating wounds 

 that develop into ugly secondary sores. 



Biologically, many gaps exist in our knowledge of African 

 Amblyomma distribution, host- preferences, especially of immatvire 

 stages, and life history. Birds are important immature- stage 



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