HAEMAPHYSA LIb 



INTRODUCTION 



Haemaphysalids are so small and inconspicuotis, except when 

 the females become greatly engorged, that they are seldom ade- 

 qiiately represented in collections. Collectors frequently over- 

 look them when larger and more colorful ticks are present. Many 

 species show a marked predilection for seldom examined hosts 

 svich as hyraxes, birds, and hedgehogs. Some haemaphysalids 

 appear to be actually quite rare in nat\ire. 



In tropical and southern Africa, the genus Haemaphysalis is 

 represented by the ubiquitous H. leachii subspp. , chiefly a car- 

 nivore parasite, and by approximately fifteen less common species. 

 In the nearby Madagascan archipelago, among whose ten known endem- 

 ic tick species axe nine haemaphysalids, most are distinctly re- 

 lated to the Oriental fauna. Asia has some fifty or more haemaphy- 

 salid species, which, in proportion to the total tick fauna, are 

 to that continent what rhipicephalids are to Africa. A dozen 

 forms are listed in the Russian fauna (Pomerantzev 1950). Of a 

 total of eighteen ixodid species in the Philippines (Kohls 1950) > 

 not including the cosmopolitan kennel tick, one third are haema- 

 physalids. The Americas and Europe claim only about five species 

 each. 



Since Nuttall and Warburton's (1915) revision of this genios, 

 the African haemaphysalid favina has received but little attention 

 from biologists, systematists , or collectors. Many records in- 

 cluded here represent considerable extensions of known range. 

 Obviously, some few African species remain to be discovered sind 

 described. Differentiation of most African haemaphys6Llids is 

 relatively easy, either by certain combinations of characters or 

 by unique characters for individual species. Morphological char- 

 acters and facies of most species are comparatively quite constant. 

 An important exception is H. leachii subspp., among the African 

 forms of which there is very considerable variation. 



Haemaphysalids are usually three-host parasites, although 

 exceptions do occur. The life cycles of H. 1. leachii and of H. 

 aclculifer have been fairly well studied in the laboratory, bu^ 



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