323 

 -eech and Chandler: Coleoptera 



— Hind coxal processes spinous apically 3 



2. Hind coxal processes broadly rounded; apices of hind 

 trochanters blunt; middle coxae less widely separated, 

 metasternum between middle coxae narrower than 

 greatest width of prosternal process; adhesive pads 

 on 2nd and 3rd middle tarsal segments of male uniformly 

 dense; elytra of female sulcate (fluted) in basal two- 

 thirds; length 24-26 mm.; British Columbia, to Humboldt 

 County hatchi Wallis 1950 



— Hind coxal processes bluntly pointed; apices of hind 

 trochanters sharply pointed; metasternum between 

 middle coxae broader than greatest width of prosternal 

 process; adhesive pads on 2nd and 3rd middle tarsal 

 segments of male each divided longitudinally by a 

 nearly median bare space; elytra of female smooth, 

 as in male; length 27-30 mm.; Alaska to Baja California, 

 Alberta to Colorado marginicollis LeConte 1845 



3. Dorsum of head with a narrow pale margin adjacent 

 to eyes; abdominal sternites pale; form narrower; 



Palearctic, Alaska to Manitoba; California ? 



anxius Mannerheim 1843 



— Dorsum of head not pale adjacent to eyes, except 

 at front corners; abdominal sternites black, broadly 

 pale along hind margins; form broader; Palearctic; 

 Alaska to New Hampshire, Sierra south at least to 

 Fresno County dauricus Gebler 1832 



Key to the California Species of Cybister 



Adults 



1. Outer posterior angle of hind femur acute, produced 

 posteriorly in both sexes; female with only a single 

 claw on hind tarsus, and without sexual sculpture 

 on elytra; Nevada to Baja California; Butte County 



to Imperial County explanatus LeConte 1852 



— Outer posterior angle of hind femur not produced, 

 not acute; female with rudimentary 2nd claw on hind 

 tarsus and with sexual sculpture of impressed lines 

 on sides of head and pronotum, and elytra except 

 near suture; Texas to Arizona, Imperial County to 

 San Diego County ellipticus LeConte 1852 



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