624 MEDICAL ENTOMOLOGY 



Female. (Plate LXXII, fig. 6) Scutum heart-shaped, broader than long, 

 with three green spots situated in the angles. Length 4 to 10 mm. ; 

 width 3'5 to 7 mm. (Neumann). 



This species is found in most parts of India, Burma and Ceylon ; 

 it is also recorded from Java, Senegal, Luango and Togo Land ; it is 

 chiefly parasitic on snakes, but also occurs on lizards of the genus 

 Varanus. 



GENUS DERMACENTOR, KOCH, C.L. 



Eyes flat. Capitulum short with rectangular base ; palps short and 

 thick ; second segment not humped externally. Body nearly always much 

 longer than broad. Scutum with light markings. Spiracles nearly 

 always in the form of a short comma. The male as a rule has eleven 

 festoons; anal groove present, but its limbs frequently do not join the 

 genital groove. Coxa I has two well-developed spurs ; coxa IV of the male 

 is much larger than the other coxae. (Neumann) 



Neumann gives the following key for the determination of the species. 

 NEUMANN'S KEY TO THE SPECIES OF DERMACENTOR 



MALES 



1. Scutum with light or dark marks. ......... 2 



Scutum dark brown without marks ...... nitcus. 



(United States ; 

 Guatemala; Venezuela.) 



2. Coxa IV with a single tuberosity on the posterior border ..... 3 

 Coxa IV with two or three small spurs on the posterior border ... 8 



3. Scutum with white spots ........... 4 



Scutum with yellow or red markings (chiefly African) 7 



4. Second article of palp much broader than long, with a dorsal 



retrograde spine . reticulatus. 



(Europe ; Persia; Japan ; United States .) 

 Second article of palp not broader or only a little broader than 



long, without a spine . . . . , . . . . . . 5 



5. Spiracles with postero-external extension well marked. . . andersoni 



(United States ; Montana.) 

 Spiracles with less marked postero-external extension ..... 6 



6. Spiracle smooth with very fine punctations ... . variabilis. 



(United States ; Mexico.) 

 Spiracle with prominent punctations . . . ;'". variegatus. 



7. Scutum with numerous markings resembling that of the female 



in front . . . , .. . . . . ... . rhinocerotis. 



(East Africa.) 

 Scutum with eight peripheral spots . . . . . '. circumguttatus. 



(Congo ; Cameroons.) 



