10 PROCEEDINGS OF THE NATIONAL MUSEUM vol. 121 



Frontal and pronotal punctures very large (fig. 100; punctures on 

 venter of abdomen teardrop shaped and lateral ones several times 

 larger than central ones; cf paramere about two-thirds length of 

 aedeagus and abruptly tapering to sharp, recurved apex; New Mexico 



to Baja California 46. chiricahuae 



9(8). Pronotum wider than long 10 



Pronotum narrow, longer than wide (measured in front of hind angles) ; 

 frontal margin scoop shaped, jutting and a little upturned. 



31. parallelus (part) 

 10(9). Pronotal punctures not so thick as to appear granulose; vestiture of 



thorax and elytra of about same length and density 11 



Pronotal punctures very dense and appearing granulose; vestiture of 

 pronotum short and fine, nearly velvety, considerably denser than 



on elytra 13. opacicoUis 



11(10). Pronotal punctures smaller than those on frons, dense and nearly con- 

 tiguous on all sides; small species, elytron length less than 7.5 mm . 12 

 Pronotal punctures sparser and larger; most species with elytron length 



7.5 mm or more 13 



12(11). Vestiture of thorax rather sparse, that on venter sparser than on dorsum; 

 antennal segment 3 intermediate in size between 2 and 4; frontal 



margin not upturned 11. lanei 



Vestiture of thorax long and thick, that on venter as long and thick 



as on dorsum; antennal segment 3 shorter, closer to length of 2 than 



4; frontal margin thin, shelflike and a little upturned ... 12. pilosus 



13(11). Frontal margin not strongly protuberant, usually without a depression 



before margin 14 



Frontal margin strongly protuberant, when viewed from side extends 

 out in shelflike extension, marked depression behind margin; 9 bursa 

 without spines or with only patch of 5-8 small spines on each side 

 near base; cf paramere with margins before apical blade straight 

 and without indentation; large species, elytron 10-12mm. 



3. decumanus 



14(13). Frontal margin well defined, dark brown or black, not weakened in 



center; elytron rarely as long as 13 mm and most species considerably 



less 15 



Frontal margm usually weakened in center, when viewed directly in 

 front appears obliterated and without black margin in center; large 

 species with elytron 11.4-14.9 mm (aver. 13 mm); ? bursa with spmes 

 in large basal packet and small, separated distal patch (fig. 5/). 



4. castanipes, females 

 15(14) . Antennal segment 4 about lYz times as long as wide and considerably wder 



than 3; elytron often less than 10 mm long 16 



Antennal segment 4 usually slender, about two times as long as wide and 

 only a little wider than 3; average elytron length 10.8 mm; cf gono- 

 style with thick patch of 30-40 long, soft hairs on apical blade (fig. le) ; 

 9 bursa with dense packet of long, close-set spines arranged nearly in 



trapezoid (fig. 5e) 2. spadix 



16(15). Pronotal punctures smaller than those on front, those in center generally 

 separated by at least own diameter; elytron usually less than 8 mm 

 long; cf aedeagus parallel sided until near apex and sharply tapering 

 to acute tip 17 



i 



