504 PROCEEDINGS OF THE NATIONAL MUSEUM vol. ni 



Type data. — ^Holotype male and allotype female (both UnivTuc), 

 "Tucuman Argentina Amaicha del Valle, Nov. 1945, A. Willink." 

 Paratypes: One male, nine females, as follows: 



Argentina: Tucumdn: Amaicha del Valle, November 1945, A. Willink, 1 male, 

 5 females (UnivTuc, USNM, RCF). Concepci6n, December 4, R. Golbach, 1 

 female (UnivTuc). Salta: Cafayate, Feb. 20, 1949, H. J. Hayward, 1 female 

 (UnivTuc); Mar. 7, 1939, Biraben-Scott, 2 female.s (UnivNac, RCF). 



Discussion. — The presence of a submarginal row of peg-bearing 

 setigerous punctures on the jugum sets apart this species and subtilius 

 from all other members of the subgenus. But since this feature 

 appears elsewhere within this and other genera it must be an adaptive 

 character and therefore should not be used to erect categories in 

 contradiction to the less variable, phylogenetically significant, 

 nonadaptive structure of the evaporatorium and subapical impressed 

 line of the pronotum. The stout form, transverse rugae on the head, 

 the numerous lateral hairs and the differentiated spines of the posterior 

 tibia are suggestive of semibrunneus and xanthopus, while the subbasal 

 angulation on the postero ventral margin of the hind tibia reminds one 

 of aethiops and certain other species within the subgenus. 



On the basis of the locality, the submarginal row of pegs on the 

 jugum, and a reluctance to accept Signoret's work as accm'ate, the 

 author considered this form to be subtilius. However, Dr. Blote's 

 comparison of specimens with the type of that species showed their 

 distinctness. 



Pangaeus {Pangaeus) aethiops (Fabricius) 



Plate figures 14, 24, 46, 103, 127, 155, 177, 235 



Cimex aethiops Fabricius, 1787, p. 296. 



Cydnus aethiops Fabricius, 1803, p. 186. 



Cydnus serripcs Westwood, 1837, p. 19. New synonymy. 



Aethus ? aethiops Walker, 1868, p. 534. 



Pangaeus aethiops St§,l, 1868, p. 7. 



Cydnus serripes "loc. incert." StAl, 1876, p. 26. 



Aethus margo Dallas, 1851, p. 116. — Walker, 1867, p. 151. New synonymy. 



Pangaeus margo StAl, 1862, p. 95; 1876, p. 19.— Uhler, 1877, p. 387.— 

 Distant, 1880, p. 5, pi. 2, fig. 15.— Lethierry and Severin, 1893, p. 70.— Banks, 

 1910, p. 100.— Van Duzee, 1917, p. 20.— Torre Bueno, 1939, p. 180. 



Pangaeus [I] confusus Signoret, 1881a, p. 642; 1882, p. 249, pi. 8, fig. 107 (not 108 

 as stated in text). New synonymy. 



Pangoeus [!] serripes Signoret, 1882, p. 247, pi. 8, fig. 106. 



Pangoeus [!] margo Signoret, 1882, p. 248, pi. 8, fig. 108 (not 107 as stated in text). 



Pangaeus serripes Uhler, 1886, p. 3. — Lethierry and Severin, 1893, p. 70. 



Pangaeus confusus Uhler, 1886, p. 3. 



Diagnosis. — The male is easily recognized within the genus by the 

 deep medioapical emargination of the genital capsule (fig. 177); the 

 female is not so positively identified, even within the subgenus, except 



