HOSTS 



R. simpsoni has been reported only from cane (or "edible") 

 rat s ," "Thryononys {- Aulacodus) spp. and Choeronys spp. (all authors). 

 What appears to be an exceptional host is the giant forest rat, 

 Cricetomys gambianus; specimens from this host from Uganda, A. D. 

 Fraser legii , are in British 1-tuseum (Natxiral History) collections. 



BIOLOGY 



R. simpsoni appears to be almost entirely restricted to cane 

 rats." The paucity of records is possibly due to rarity of host 

 examination. Present evidence would indicate that this is one 

 of the most host-specific of rhipicephalid ticks. Although R. 

 simpsoni is closely related to R. simus, this latter species""is 



imp: 



seldom found on cane rats. 



DISEASE REIATIONS 

 Unstudied. 



REMARKS 



Adults were figured and rede scribed by Theiler (l%7) . The 

 nymph was described by Santos Dias (1952G), who, incidentally, 

 considered this species as a synonym of R. simus longus but who 

 subsequently (1952G,H) recognized the obvious validity of R. 

 simpsoni . 



Generally one may be suspicious that records of R. simus 

 from cane rats actually refer to R. simpsoni , althougH two males 

 of R. simus from a cane rat near Yirol nave been seen, (E. T. M. 

 Rei'3 legit J. All other collections, labelled as R. simus from 

 cane rats, that have been studied by the writer from various 

 parts of Africa have proven to be R. simpsoni . 



- 727 - 



