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American Midland Naturalist Monograph No. 1 



The two species occupy overlapping ranges (see maps) . It should be 

 realized too, that in the area where both species occur and use the same animals 

 as hosts there is a possibility that O. turicata and O. parkeri may have hybrid- 

 ized. In fact, Dr. Davis has interbred these two species in the laboratory 

 (unpublished) and certain field specimens from the overlapping area show 

 intergraded characters. 



Comparative studies have shown that other than the more definite charac- 

 ters which separate O. turicata and O. parkeri both as adults and nymphs, 

 such as hypostome and mammillae, there is little of value for separating the 

 two species. Both show the dorsal humps on the tarsi absent in N. 1, faint in 

 N. 2, and progressively more prominent in the successive stages to the adults. 

 O. savigny and eremicus show these humps to be very well developed in the 

 early nymphal stages. 



Photographs of all stages of both species are shown in figures 26, 27, 28, 

 and 29, and pen drawings of the hypostomes and legs of all stages in figures 



Fig. 30. Ornithodoros turicata (Duges) on the left, O. parkeri on the right. A, Third 

 stage nymph, dorsal view. B, Same, ventral view. C, Second stage nymph, dorsal view. 

 D, Same, ventral view. E, First nymphal stage, dorsal view. F, Same, ventral view. 



