42 American Midland Naturalist Monograph No. 1 



Ornithodoros coriaceus Koch, 1844 



Plate 5, Figs. 15 and 16 



1844. Ornithodoros coriaceus Koch, original description, p. 219. 



1847. Ornithodoros coriaceus Koch: Koch, redescribed, p. 31, with figures. 



1888. Argas (Ornithodoros) coriaceus Koch: Berlese, p. 193. 



1896. Ornithodoros coriaceus Koch: Neumann, redescribed, p. 31. 



1901. Ornithodoros coriaceus Koch: Neumann, redescribed, p. 258. 



1908. Ornithodoros coriaceus Koch: Banks, retescribed, p. 18-19, with figures. 



1908. Ornithodoros coriaceus Koch: Nuttall, Warburton, Cooper, and Robinson, 



redescribed, pp. 55-56, with figures. 



1911. Ornithodoros coriaeceus Koch: Neumann, redescribed, p. 124. 



1930. Ornithodoros coriaceus Koch: Hoffman, redescribed, pp. 163-164. 



1936. Ornithodoros coriaceus Koch: Brumpt, p. 1206. 



Sexes similar; nymphs and adults similar. 



ADULT 



Body. — Sub-oval, somewhat pointed anteriorly and with the sides nearly 

 parallel. Nuttall et ai. (1908) give as the size of this tick, largest female 13.8 

 x 8.2, smallest, 9.5 x 5.3; largest male 8.6 x 4.6, smallest, 6.4 x 3.4. Specimens 

 in the collections of the Rocky Mountain Laboratory are of intermediate sizes 

 for the most part but one male measures 5.6 x 3.4. 



Mammillae. — Numerous, moderate and variable in size, irregular in shape. 

 In clean specimens 5 the mammillae have the flattened tops ornate. Nuttall 

 et al. (1908) state that the color is white in living and reddish in old preserved 

 specimens. Living and freshly preserved specimens have the color reddish-gray, 

 almost iridescent, with a few punctations interrupting the color. (Color is 

 better seen in immersed specimens.) Interspersed in the mammillated areas 

 are numerous large, deep pits independent of the discs, each with a conical, 

 truncate elevation, bearing a hair. 



Discs. — Large, depressed, with surface of the floors of the depressions 

 irregular, resembling the mammillated areas. Discs less definite or absent on 

 the ventral surface. 



Legs. — Moderate in length; femur, tibia and metatarsus flared distally. 

 Hairs few, short, and inconspicuous. Subapical dorsal protuberances pro- 

 nounced on all tarsi; dorsal humps three or four on tarsi I to III: one at the 

 base on tarsus IV. Length of tarsus I, 1.23; metatarsus, 0.96. Length of tarsus 

 IV, 1.92; metatarsus, 1.5. 



Coxae. — Coxae I and II a little separated; all others contiguous. 



Hood. — Separated from the anterior dorsal projection of the body wall. 



Camerostome. — Definite and deep. 



Cheeks. — Absent. 



Capitulum. — Basis capituli broader than long; surface very irregular with 



5 Specimens of Ornithodoros collected in nature are often badly encrusted with dirt, 

 and this is particularly true of coriaceus. 



