348 



covers the dorsum entirely ; usually marked with 

 green spots. Stigmata, comma-shaped. Female, 

 scutum shorter than broad, three green spots. 

 The species are parasitic on reptiles. 



Genus Amblyomma 



Eyes present, conspicuous. Anal groove as in 

 Aponomma, anal plates absent. Rostrum long. 

 Scutum often has coloured designs. Stigmata 

 usually triangular, nearly always eleven posterior 

 marginal festoons in the male. There are over 

 eighty species. 



A. variegatum. — Is frequent on cattle in 

 Rhodesia. 



Genus Hyalomma 



Eyes present, conspicuous. Rostrum long. 

 Anal groove opens anteriorly. Body elongate 

 oval. Colour deep-brown. Male, two pairs of , 

 ventral shields, two perianal, large, triangular, 

 and two small external. Scutum covering nearly 

 the whole of the dorsum. Crenellated or festooned 

 posteriorly. Male, stigmata comma-shaped, with 

 a long tail ; female, stigmata with a short tail. 

 Three species only. 



H. aegyptium. — Attacks cattle especially, also 

 dogs and cats. Occurs in Egypt, North and South 

 Africa. 



Argasidae. — Scutum absent, rostrum inferior 

 (except in larva). Stigmata between third and 

 fourth legs. Pulvillum of tarsi wanting in adult. 

 Palpi, free, short, filiform, four segments. Tegu- 

 ment leathery, without dorsal or ventral shields. 

 Sexual dimorphism not marked. 



Genus Argas 

 Eyes absent. Rostrum, which is concealed 



