CYDNIDAE OF THE WESTERN HEMISPHERE — FROESCHNER 633 



While the above arrangement may be of interest and aid in placing 

 male specimens, a key which will enable one to determine both sexes 

 to species is more valuable. Such a key is given here: 



Key to species of Amnestus 



1. Jugum with five (occasionally more) marginal pegs (fig. 61)11 2 



Jugum with four marginal pegs (fig. 64) 15 



2. Clypeus surpassing juga by a length equal to or greater than its own width; 



prosternal carinae longer than high, ventral margin feebly convex. 



uhleri Distant (p. 663) 



Clypeus not or only slightly surpassing (much less than its own width) 



juga 3 



3. Labium long, reaching or surpassing base of abdomen. 



spinifrons (Say) (p. 658) 

 Labium short, not surpassing middle coxae 4 



4. Exocorium with costal half hyaline, impunctate or very feebly punctate; 



prosternal carinae (in profile) concave ventrally (fig. 40). 



trimaculatus, new species (p. 661) 

 Exocorium uniformly punctate across full width 5 



5. Pronotal umbones distinctly, closely punctate over full .surface 6 



Pronotal umbones polished, mostly impunctate 8 



6. Prosternal carinae (in profile) distinctly concave ventrally (as in fig. 40) ; 



pronotum unicolorous blackish brown 7 



Prosternal carinae much longer than high, not or very feebly concave ven- 

 trally; posterior pronotal lobe yellow like coria, distinctly paler than 

 brown anterior lobe forreri Distant (p. 645) 



7. Anteocular part of juga coarsely sculptured to apex. 



cribratus (Stai) (p. 642) 

 Anteocular part of juga polished, virtually without sculpturing. 



championi Distant (p. 640) 



8. Clypeus with six apical pegs, the usual marginal four plus two on midline, 



one above and one below margin; posterior pronotal lobe distinctly lighter 



than anterior lobe sexdentatus, new species (p. 657) 



Clypeus with not more than four apical pegs 9 



9. Prosternal carinae (in profile) lobulate, vertical anteriorly (fig. 38). 



subferrugineus (Westwood) (p. 660) 

 Prosternal carinae rounded or longer than high, not vertical anteriorly . . 10 



10. Prosternal carinae about twice as high as labial II, semicircular, with promi- 



nent, deep fovea laterally near base (fig. 39). 



foveatus, new species (p. 647) 

 Prosternal carinae distinctly lower than labial II, without fovea . ... 11 



11. Clavus and usually coria distinctly paler than scutellum and most or all of 



pronotum 12 



Clavus and corium concolorous with pronotum and scutellum. 



pallidus Zimmer (p. 650) 



11 This choice will also lead to Distaut's four specws—beTgrothi, dallasi, signoreti, and stall (see p. 604 for 

 further comments on these forms). 



