388 PROCEEDINGS OF THE NATIONAL MUSEUM vol. lie 



Distribution. — Arizona, New Mexico, and adjoining areas. 



Prey record. — None. 



Plant record. — As indicated under paratypes. 



19. Cerceris krombeini, new species 



Figures 23, 122a,b,c, 



Female. — Length 10 mm. Black with yellow markings ; punctation 

 coarse; pubescence very short. 



Head sUghtly wider than the thorax; black except large frontal 

 eye patches, patch on the upper surface of the clypeal process, 

 patch back of the eye, base of mandibles, and a patch on the scape, 

 all of which are yellow; clypeal border with four denticles, the medial 

 pair separated from each other by a deep depression and somewhat 

 larger than the lateral pair; clypeal process with the free margins 

 converging to a blunt point, below which is a pair of prominent 

 denticles; mandibles with one distinct denticle flanked on each side 

 by a low and indistinct denticle; antennae normal in form. 



Thorax black except for a divided band on the pronotum, two 

 patches on the scutellum, the metanotum, a small patch on the 

 pleuron, and the tegulae, all of which are yellow; tegulae slightly 

 inflated and smooth; enclosure smooth except for a medial groove and 

 deep pits in the lateral angles; mesosternal tubercles small but very 

 acute; legs black on the basal segments to or just beyond the middle 

 of the fore- and midfemora, beyond which they are yellow, the hind- 

 femora entirely black or fuscous, the hindtibiae yellow basally, 

 fuscous apically, and the hindtarsi fuscous; wings subhyaline, clouded 

 apically, and the stigma bladk. 



Abdomen with a semidivided patch on tergum 1, a broad band 

 with rectangular emargination on the basal end of tergum 2, broad 

 but deeply emarginate bands on terga 3 and 4, a broad band on 

 tergum 5; venter immaculate; pygidium with the sides convex and 

 the ends subequal and rounded. 



Male. — Length 8 mm. Black with light yeUow markings; puncta- 

 tion coarse ; pubescence very short. 



Head about one-sixth wider than the thorax; black except for 

 the entire face, base of mandibles, and scape, all of which are hght 

 yeUow; clypeal margin with three denticles on the medial lobe, the 

 medial denticle slightly the largest; hair lobes subequal in width to 

 the lateral clypeal lobes; surface of the medial clypeal lobe normally 

 convex; mandibles with two very low denticles; antennae normal 

 in form. 



Thorax black except for a divided band on the pronotum, two 

 spots on the scutellum, the metanotum, and the tegulae, all of which 

 are light yellow; tegulae distinctly elevated but smooth; enclosure 



