244 BULLETIN 14 5, UNITED STATES NATIONAL MUSEUM 



tinct narrow median depression extending from base to near anterior 

 margin, a vague depression on each side along lateral margin, and 

 with distinct, arcuate prehumeral carinae, extending from the pos- 

 terior angles to near the middle; surface rather finely, transversely 

 rugose, the rugae more or less longitudinal at the sides, sparsely, 

 finely punctate between the rugae, and with a few inconspicuous 

 hairs at the sides. Scutellum strongly, transversely carinate, and 

 the surface finely, densely reticulate. 



Elytra slightly wider than pronotum at base, and about equal in 

 width at base and apical third; sides nearly parallel for a short 

 distance behind the base, feebly, broadly constricted in front of 

 middle, broadly, arcuately expanded behind the middle, then ob- 

 liquely narrowed to the tips, which are separately, rather broadly 

 rounded, and finely serrulate ; abdomen broadly exposed above ; disk 

 feebly flattened, sutural margins strongly elevated posteriorly, and 

 with broad, moderately deep, basal depressions; surface coarsely, 

 densely imbricate-punctate, and each elytron ornamented with a nar- 

 row vitta of sparsely placed, short, recumbent, white hairs, extending 

 from the basal depression to apex. 



Abdomen beneath finely, sparsely punctate posteriorly, the punc- 

 tures denser and connected transversely by sinuate lines on basal 

 segments, and sparsely clothed with short, inconspicuous hairs; first 

 segment feebly, broadly longitudinally grooved at middle; last seg- 

 ment broadly rounded or subtruncate at apex; vertical portions of 

 segments sparsely clothed with moderately long, white hairs; pygi- 

 dium finely, sparsely punctate, and not longitudinally carinate. 

 Prosternum finely, sparsely punctate, and sparsely clothed with long, 

 semierect, whitish hairs; prosternal lobe broad, strongly declivous, 

 and broadly rounded or subtruncate in front; prosternal process 

 broad, slightly expanded behind the coxal cavities, then abruptly 

 narrowed to the apex, which is acute. Tibiae slender, and the ante- 

 rior and middle pairs armed with a short tooth on inner margin at 

 apex. Posterior tarsi slightly shorter than the tibiae, and the first 

 joint as long as the following two joints united. Tarsal claws sim- 

 ilar on all feet, cleft near the middle, the inner tooth broad, shorter 

 than the outer one, and not turned inward. 



Female. — Differs from the male in having the lateral margins of 

 head parallel, surface not distinctly granulose, more sparsely punc- 

 tured, more or less irregularly rugose, the pubescence sparser and 

 shorter, and the color varying from brownish cupreous to bronzy 

 cupreous ; first abdominal segment convex, and not sulcate at middle ; 

 prosternum smoother, the pubescence sparser and more recumbent, 

 and the tibiae unarmed at apex. 



Length, 3.1-4.25 mm.; width, 0.87-1.12 mm. 



Type locality. — Williams, Ariz. 



