NORTH AMERICAN BUPRESTID BEETLES 9 



15. Vertical portions of abdominal segments, and abdomen beneath with distinct 



pubescent spots (9) difficilis Gory. 



Vertical portions of abdominal segments without distinct pubescence spots, 

 but sometimes uniformly clothed with pubescence over entire surface; 

 abdomen beneath without distinct pubescent spots 16. 



16. Claws on anterior tarsi with the inner teeth distinctly separated at the 



tips 17. 



Claws on anterior tarsi with the inner teeth contiguous or nearly contiguous 

 at the tips 19. 



17. Body above distinctly, sparsely, uniformly pubescent ; elytra with distinct 



costae (13) townsendi Fall. 



Body above not distinctly pubescent ; elytra without distinct costae 18. 



18. Male with the claws on anterior tarsi feebly cleft, the inner tooth distinctly 



broader than outer one, and broad toward apex. Host plants : Madrone 



or manzanita (14) arbuti Fisher. 



Male with the claws on anterior tarsi deeply cleft, the inner tooth not dis- 

 tinctly broader than outer one, and acute at apex. Host plant : Oak. 



(15) angelicus Horn. 



19. Male with anterior and middle tibiae armed with a distinct tooth on inner 



margin at apex 20. 



Male with all tibae armed with a distinct tooth on inner margin at apex_ 23. 



20. Posterior tarsi of male shorter than tibiae, the first joint as long as the 



following three joints united 21. 



Posterior tarsi of male as long, or longer than tibiae, the first joint as long 

 as the following four joints united (16) masculinus Horn. 



21. Elytra sparsely, uniformly clothed with distinct whitish pubescence. 



(17) albocomus Fisher. 

 Elytra without distinct pubescence 22. 



22. Elytra with vague pubescent vittae. 



(18) paramasculinus Champlain and Knull. 

 Elytra without pubescent vittae (19) arcuatus (Say) and subspecies. 



23. Male with antennae longer than pronotum, slender, and ciliate beneath with 



long hairs (20) crinicornis Horn. 



Male with antennae not longer than pronotum, and not ciliate beneath 24. 



24. Male with the last ventral abdominal segment truncate and fimbriate at 



apex (21) def ectus LeConte. 



Male with the last ventral abdominal segment not fimbriate at apex 25. 



25. Male with the prosternum conspicuously pubescent 26. 



Male with the prosternum not conspicuously pubescent 28. 



26. Male genitalia with the sides arcuately expanded 27. 



Male genitalia with the sides parallel (22) geminatus (Say). 



27. Male with front of head densely clothed with long, white hairs behind 



epistoma, and nearly concealing the surface; sides of male genitalia not 



transparent at apex. Host plant: Hickory (23) otiosus Say. 



Male with front of head sparsely clothed with white hairs behind epistoma ; 

 sides of male genitalia broadly transparent toward the apex. Host plant : 

 Probably hazel (24) atricornis Fisher. 



28. Male with the second abdominal segment transversely concave, and causing 



the body to be bent downward. Host plant : Black walnut. 



(25) transimpressus Fall. 

 Male with the second abdominal segment not transversely concave 29. 



