Cooley & Kohls: Argasidae of N. America, etc. 21 



Genus OTOBIUS Banks, 1912 



/912 Otobius Banks, p. 99, original description. 



Adults and nymphs dissimilar and with sexes similar. Adults with the 

 integument granulated; nymphs striated and with spines. Without change of 

 pattern of the integument at the sides. Capitulum distant from the anterior 

 margin in adults; near the margin in nymph. Hood and eyes absent. Hypo- 

 stome of nymphs well developed; vestigial in adults. 



Genotype: Argas megnini Duges, 1884, original monotype. 



Key to Species of Otobius 

 Adults 



The numerous pits on the dorsum separated by a distance of twice or more the 



diameter of one pit megnini (p. 21) 



The numerous pits on the dorsum separated by a distance of the diameter or less, 



of one pit lagophilus (p. 32) 



Nymphs 



Integument with numerous heavy spines anteriorly and lighter spines posteriorly; 



hypostome with denticles 4|4; spiracles conical megnini (p. 23) 



Integument with numerous spines all of one size; hypostome with denticles 3|3; 



spiracles convex lagophilus (p. 34) 



Otobius megnini (Duges), 1884 



Plate 2, Fig. 6, 7, 8. 9 and 10 



1884. Argas megnini Duges, original description, pp. 197-198, with figures. 



1885. Argas megnini Alf. Duges: Megnin, redescribed, pp. 466, 472-475, with figures. 

 1893. "Argas americana Packard": Townsend, p. 50. 



1895 Rhhnchoprium spinosum G. Marx, figures only, p. 199, Marx obituary notice. 



1896. Orniihodoros megnini (Alf. Duges) : Neumann, redescribed pp. 42-44. 



1901. Omithodoros megnini (Duges): Salmon and Stiles, redescribed, pp. 408-414, 



with figures. 

 1908. Orniihodoros megnini Duges: Banks, redescribed, p. 17, with figures. 

 1908. Omithodoros megnini (Duges) 1883: Nuttall, Warburton, Cooper and Robinson, 



redescribed, pp. 71-77, with figures. 



1911. Omithodoros megnini (Alf. Dug.): Neumann, p. 125. 



1912. Otobius megnini Duges: Banks, new genus proposed, p. 99. 



1930. Omithodoros (Otobius) megnini Duges, 1882: Hoffman, redescribed, pp. 151 — 



155, with figures. 

 1932. Argas megnini Duges: Bedford, p. 280. 

 1934. Argas megnini Duges: Bedford, pp. 77-81. 

 1936. Omithodorus megnini (A. Duges): Brumpt, p. 1209. 



ADULT 



Body. — Panduriform, rounded behind and slightly attenuated anteriorly; 

 broadest at legs II and III, constricted just behind leg IV. Both Salmon and 

 Stiles (1901) and Nuttall et at. (1908) give as the size of the female, 6.0 x 

 4.0 to 5.0 x 3.0. In the collections of the Rocky Mountain Laboratory we have 

 females as large as 8.25 x 6.00. Males are a little smaller. Specimens of adults 

 preserved in alcohol are enclosed by a thin, translucent covering which is easily 



