A REVISION OF NORTH .AMERICAN CHRYSOBOTHRINI 111 



Pronotuni one and one-half times as wide as long, slightly wider at apex than 

 at base, widest near apex ; sides nearly parallel anteriorly, strongly constricted 

 at posterior angles ; anterior margin slightly sinuate, with a broadly rounded 

 median lobe ; base broadly, arcuately emarginate on each side, median lobe mod- 

 erately produced, and truncate in front of scutellum; disk uniformly convex, 

 without depressions or callosities, but with an indistinct, smooth, longitudinal, 

 median spot on basal half; surface finely, densely granulose, densely, deeply 

 punctate on median part, more coarsely, confluently punctate toward sides, 

 sparsely clothed with whitish hairs near posterior angles. 



Elytra distinctly wider than pronotum, nearly twice as long as wide; sides 

 nearly parallel from humeral angles to apical third, then arcuately converging 

 to tips, which are separately broadly rounded ; lateral margins rather coarsely 

 serrate posteriorly; basal depressions broad and deep; humeral depressions 

 elongate and shallow; surface uneven, without distinct pubescence, coarsely, 

 densely, deeply punctate, becoming confluently punctate and more or less scabrous 

 at sides and toward apices; each elytron with a rather deep, transversely oval 

 depression in front of middle, and a rounded, shallow depression just behind 

 middle near lateral margin, but without distinct longitudinal costae. 



Abdomen beneath finely, irregularly punctate on median parts, more densely 

 punctate toward sides, smooth along anterior and posterior margins of sternites, 

 sparsely, irregularly clothed with moderately long, recumbent, whitish hairs, 

 without smooth lateral callosities, intervals finely granulose ; last visible sternite 

 broadly, deeply, arcuately emarginate at apex, without a submarginal ridge, 

 lateral margins slightly, irregularly serrate; eighth tergite deeply, triangularly 

 emarginate at apex, densely granulose, coarsely, densely punctate, but not longi- 

 tudinally carinate. Prosternum coarsely, densely rugose, confluently punctate, 

 rather densely clothed with long, recumbent, white hairs ; anterior margin with 

 a distinct, large, narrow, median lobe. Anterior femur with a short, obtuse 

 tooth, which is dentate on outer margin. Anterior and middle tibiae slightly 

 arcuate, the former armed with a small, rounded dilation near apex ; posterior 

 tibia straight. 



Length 6.75 mm., width 2.75 mm. 



Female. — Differing from the male in having the head uniformly coppery red 

 and more sparsely pubescent, the prosternum more sparsely pubescent, the last 

 visible sternite more shallowly emarginate at apex, the eighth tergite rounded 

 at apex and longitudinally carinate, the middle tibia straight, and the anterior 

 tibia unarmed near apex. 



Re described from the male type and female allotype, No. 51938, in 

 the United States National Museum. 



Type locality. — Independence, Owens Valley, Calif. 



DISTRIBUTION 



From material examined: 



Arizona: Williams, May to July (Barber and Schwarz) ; July 29 (H. F. Wick- 

 ham). Ash Fork, June 18; Bright Angel, July 10 (Barber and Schwarz). 



California: Independence, Owens Valley, July 17; types (H. F. Wickham). 

 Sunset Valley, Santa Barbara County, July 4, 1939 (W. F. Barr and M. 

 Cazier). 



Nevada: Reno, July 18 (H. F. Wickham). * 



Hosts. — The larval habits are unknown, but the adults were col- 

 lected by Wickham in California by beating desert shrubs, and by 

 Barber and Schwarz in Arizona on antelope brush (Purshia triden- 

 tata (Pursh) DC). 



Some specimens are more coppery red than others, and the color 

 of the foveae on the elytra varies from coppery to green. The sides 

 of the pronotum are rounded in some of the specimens. The apex of 

 the last visible abdominal segment of the female is slightly variable 

 in shape. The length is from 5.5 to 7.75 mm. 



