324 AMERICAN PACHYBRACHYS (cOLEOPTERA) 



anterior, and two oblicjue basal spots, the lateral margin and a verj' nar- 

 row anterior margin, yellow 9 



3. Elytra with a narrow subsutural vitta — often interrupted — and the lateral 



and apical margins, yellow; prothorax with two basal spots and a median 

 anterior spot or line, yellow. 



Legs almost entirely rufo-testaceous. (Maine; Michigan.) 



141. autolycus var. difficilis* 

 Legs dark in great part. (Utah; Montana.) 



141. autolycus var. wahsatchensis* 



Elytra similarly marked, but with the sutural vitta and external margins 



obscure rufous and often almost completely obsolete; prothorax with at 



most only faint traces of markings 142. nigricornis 



Elytra without sutural vitta 4 



4. Front claws of cf very strongly enlarged; black, prothorax red varying to 



black with red side margins 153. hybridus 



Front claws of c? not or scarcely enlarged (except subfasciatus, in which 

 they are moderately so) 5 



5. Punctures of prothorax elongate laterally, with a distinct tendency toward 



strigosity; black with external margins of thorax and elytra pale yellow or 



yellowish white 140. praeclarus 



Prothorax normally punctured, pale areas of eh'tra red or reddish 6 



6. Side margins of prothorax yellowish white (rarely entirely black), head and 



legs often spotted with yellowish white; elytra orange red with a broad 



black sutural stripe not attaining the apex 154. discoideus 



Side margins of ])rothorax never yellowish white, legs and usually the head 

 entirely black, or virtually so 7 



7. Prothorax with distinct entire smooth median line; prothorax and elytra 



with wide red border, which may become partially or completely inter- 

 rupted at the elytral convexity 155. marginatus 



Upper surface dull red, the prothorax with three small basal black sjjots; 



elytral disk sometimes clouded var. sanguineus 



Prothorax without distinct median smooth line 8 



8. Prothorax entirely black, elytra with a broad red margin interrupted ut the 



convexity 156. cruentus 



Prothorax margined with red or reddish yellow. 



Elytra with a large subquadrate spot extending from the margin § to 



suture, and apical spot, red 157. dilatatus 



Elytra with a broad irregular or indented median fascia, often inter- 

 rupted at the suture, and apical spot, red 60. subfasciatus 



9. Prothorax more or less strongly shining, either polished or finely alutaceous. 10 

 Prothorax alutaceous, lustre dull or but slightly shining 15 



10. Elytral punctuation confused, without trace of serial arrangement except 



in the imperfect submarginal stria 116. varicolor* 



Elytral punctures more or less obviously arranged in impressed lines later- 

 ally and posteriorly 11 



11. Size larger, more robust, pale markings red or reddish yellow. 



Prothoracic punctuation dense. (Texas.) 152. instabilis 



Prothoracic punctuation sparse. (Arizona.) 151. vulnerosus 



