DISEASE RELATIONS 



MAN ; Evidence that this tick transmits boutonneuse fever 

 (Rickettsia conorii ) appears to be entirely presumptive. The 

 bite may in itself re stilt in severe inflammation, but man is 

 probably seldom attacked by this tick. Q fever (Coxiella biirnetii ) 

 is claimed to have been fovmd in specimens from Portugese Gviinea. 



CATTLE ; Redwater or Texas fever (Babesia bigimina ). Spiro- 

 chetosis (Borrelia theileri ) . G allsickness (Anaplasma marginale ) . 

 Not a vector or heartvater ( Rickettsia nnninantium j . The virus 

 of "a specific transmissable petechial fever of cattle" starvives 

 in this tick. 



HORSES , SHETT , and GOATS ; Spirochetosis (B. theileri ). Not 

 a vector of equine piroplasraosis (Babesia equi H 



PIGS ; Possibly a vector of porcine babesiosis (Babesia traut - 

 manniX 



Domestic animals may be so severely irritated that their health 

 is impaired and deaths from the bloodsucking of huge numbers of 

 B. decolor at us have been recorded. 



A toxin from the egg of B. decolor at us has been described. 



IDENTIFICATION 



Males are easily determined by the presence of a small tail- 

 like caudal appendage, which varies considerably in size, on the 

 posterior body margin and by a narrow spurlike elongation of the 

 internal margin of the adanal shield, which reaches to or more 

 commonly extends beyond the posterior body margin. The unique, 

 small bristle-bearing protuberance on the internal ventral s;ir- 

 face of the basal palpal segment is most importemt; this feature 

 may be difficult to discern in small specimens and the bristles 

 are often broken, though the knobs may usually be seen. Hypo- 

 stome dentition is 3/3 » rarely 3.5/3*5. Size is very small, 

 about 2.7 mm. long aiid 1.5 mm. wide. 



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