94 



Annals oe the Tkansvaal Museum, 



Females. 



A. Anal grooves converging behind the anus, but not joining. 



B. Dorsal shield as wide as long ; anal groove with branches: 

 not so close together at posterior end ... ... pilosus, 



BB. Dorsal shield longer than wide ; anal groove with 

 l)ranches closer together at posterior end 



pilosus howardi. 



AA. Anal grooves parallel behind the anus... ... ruhiciindus. 



IXODES PILOSUS, KOCH. 



Sheep Paralysis Tick. 



' ' Lvodes pilosus, Koch (1844, 1847). 



Lrodes pilosus, Koch (Neumann, 1899). 



Male. — Bodij oval; wider and rounded behind; length o. 15 inni. ^ 

 width 1.6 mm. ; colour clear reddish brown. Shield convex, covering 

 all the dorsal surface, except a narrow marginal cushion, which is 

 lighter coloured, shining, glabrous; cervical grooves of the normal 

 length, well formed, punctuations very fine, abundant. \ entrat 

 surfaee with genital pore wide, opposite coxae III; pregenital shield 

 trapezoidal ; anal shield small, longer than Avide, sides curved and 

 converging like a horseshoe; anus with three hairs on each valve. On 

 all the surface of the l)ody many hairs, those on the ventral surface 

 short and translucent, those on the epimeral shields reinforced at the 

 base. Rostrum elongate; base twice as wide as long, in shape of a 

 trapezoid opening in front on the dorsal surface, a little longer than 

 wide on the ventral surface, where it is pentagonal in outline ; 

 mandibles with inner apophysis of dig:it applied to the dorsal surface 

 in the anterior, where it has the appearance of being doubled ; three 

 teeth, the terminal small, the median one strong, and the basilar one 

 weak, the outer apophysis with seven or eight teeth, the anterior ones 

 progressively decreasing, and forming a crest, the posterior ones very 

 strong ; hypostome witli a marginal series of six to eight teeth on each 

 side, increasing in size from top to base ; the remainder of the teeth 

 are reduced to single transverse crenulations ; palpi compressed from 

 top to bottom, dorsal face flat, ventral face excavated, hairs scattered 

 over the dorsal surface, in series on the inner margin. Legs slender; 

 coxae elongate, coxae I with a strong spine on the postero-median 

 edge ; hairs on all the articles of the legs ; tarsi slender, forming in 

 leg I about a quarter of the length of the leg. 



Female. — When unengorged, hod/y flat, oval in outline, much 

 wider and rounder behind; colour yellowish red; long whitish hairs 

 on all the surfaces; when engorged resembles a castor-oil bean, slightly 

 flattened, and becomes of a dark bluish black colour. Shield yellowish 

 brown, lighter than the abdomen when young', glabrous, oval, some- 

 what pentagonal in outline, as wide or almost as Avide as long ; 

 posterior lateral margins almost straight ; cervical groove pronounced, 

 reaching the posterior margin; lateral grooves Avell marked, and 

 reaching the posterior margin ; punctuations very hne, equal on all 

 the surface ; a fcAv short, AA-hitish hairs ; integument with a fcAv hue 



