262 PROCEEDINGS OF THE NATIONAL MUSEUM Vou. 113 
Lordsburg, June 9, July 2 (Howden). oTERo co.: Cloudcroft (USNM); White 
Sands, Nov. 1 (USNM). tuna co.: Deming, July 11 and 12, Sept. 16 and 20 
(USNM). 
Texas: BREWSTER Co.: Chisos Mountains, July 17-19 (CAS); 5 miles east of 
Marathon, June 7, 5 miles west of Alpine, June 7 (Howden). EL PAso co.: El 
Paso, May 12, June 5 (USNM). srr pDAvis co.: 4 miles west of Fort Davis, 
July 15, 28 miles west of Fort Davis, July 19 (Howden). preEsrp10 co.: Marfa, 
May 15 (CU), July 3-6 (USNM); near Presidio, April 4 (USNM). 
Total specimens examined: 158. 
Subgenus Pachyphanes Dietz, 1894 
Pachyphanes Dietz, Trans. Amer. Ent. Soc., vol. 21, p. 115, 1894. Type species, 
by original designation: Pachytychius discoideus LeConte, 1876. 
DescrirTion: Rostrum strongly curved in both sexes (except in 
S. corpulentus LeConte), shorter and stouter in male; smoother and 
more polished before the antennal insertions in female (fig. 5). 
Antennae inserted slightly before middle in the female (fig. 5), well 
before the middle in male. Second segment of antennal funicle dis- 
tinctly longer than third segment; antennal club more abruptly 
distinct from funicle than in other subgenera (figs. 31-34). External 
lobes of mandibles not well developed (fig. 45). Prosternum emar- 
ginate at anterior margin and concave; antecoxal ridges indistinct 
(fig. 35). Body form stouter, more convex dorsally and laterally 
than in other subgenera (compare figs. 1, 4, 6, 8). Median lobe 
of male genitalia short, much as in subgenus Smicronyz, middorsum 
lightly sclerotized and sides subparallel (figs. 72-75). Arms of 
spiculum ventrale of female genitalia forming a rather angular U 
(fig. 121). 
Host piants: Most of the plants recorded as hosts to species in 
this subgenus belong to the family Compositae, but there are some 
exceptions (see table 1, p. 193). 
DisrripuTion: Species of this subgenus are known to occur only 
in North America. 
Key to Species Groups of Subgenus Pachyphanes 
1. Prothorax and elytra both marked with a dorsal macula of dark-brown 
scales, the rest of the scales white or near white . . discoideus group (p. 268) 
Prothorax and elytra not marked with a dark dorsal macula .... . 2 
2. Body color black, punctures of disk of prothorax transversely oval, interspaces 
raised to form transverse rugae. . . . . . . . lineolatus group (p. 275) 
Body color mostly reddish brown, punctures not transversely oval, but 
subconfluent, the interspaces forming rugae which run anterolaterally from 
santo lbh) GG BGC 2 0s 8 « es 4s © « #/s a »@moenus group (p.262) 
SMICRONYX AMOENUS GROUP 
Description: Prothorax strongly rounded on sides, strongly 
narrowed and slightly constricted toward apex; punctures of disk 
