and lower average relative humidity probably modify this tick's 

 ecological thresholds (HH). 



In southern Africa, low temperature and high altitude do 

 not in themselves limit the range of H. truncatum . It occurs 

 in sill types of South African vegetation except in short grass 

 of the highveld, a mountainous zone associated with high rain- 

 fall, and is rare or absent where snow falls. 



From the size and variety of collections examined, it apu 

 pears that in conqjarison with H. rufipes , H. truncatum may be 

 somewhat less numerous and more widely ranging in southern 

 Africa but that the reverse is true towards and beyond the 

 equator. This matter, however, requires more careful study. 

 H. truncatum is rare or never present in the forests of western 

 Ifrica. 



This species was not collected in high rainfall areas of 

 the Cameroons (Unsworth 1952), and is unusual if not entirely 

 absent on the humid west bank of Equatoria Province in the 

 Sudan. 



In Northern Province of Nyasaland, where H. truncatum is 

 the only species of this genus that is found, Temales engorge 

 on cattle chiefly during the dry season (March, April, May) 

 but also in small numbers during other months of the dry sea- 

 son. Nymphs were found on hares early in the rainy season 

 (October) and also in December (Wilson 1946). 



Adults attach in the brush of hair at the tip of the tail, 

 between the hooves, in the inguinal and perianal areas, and on 

 the scrotum and udders. 



A hymsnopteran parasite, Hunterellus theilerae , has re- 

 cently been described from nymphs of H. truncatum of Southwest 

 Africa and from nymphs of Rhipicephalus oculatus 'from Transvaal 

 (Fiedler 1953). Cooley (1934) reared Hunterellus hookeri from 

 nymphs of "H. aegyptiuirf ' in South Africa, but it appears that 

 he included~both H. trxincatum and H. nifipes under this name. 



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