A STUDY OF THE GENUS MONOXIA — BLAKE 151 



Elytra usually darkly marked with transverse dark areas at 

 base, at middle, and near apex at the suture, apex pale; 

 aedeagus rather short and stout with a fine, narrow tip. apicalis, new species 



Elytra usually without heavy sutural darkenings; aedeagus 



long, slender, and tapering brisleyi, new species 



Aedeagus long and slender, with a dorsoventrally flattened 



apex. 



6 



•Aedeagus -shorter and robust and not with a dorsoventrally 



flattened apex 10 



6. Beetles large (4 to 5.3 mm.) -- 7 



Beetles smaller (2 to 4 mm.) - 8 



7. Pronotum with prominent hind angles; Western United States, 



feeding on Chenopodiaceae angularis LeConte 



Pronotum without prominent hind angles; Florida, southeastern 



Texas, and eastern Mexico, feeding on Batis maritima.. batisii Blatchley 



8. Narrowly oblong, slender, prothorax with lateral sides angulate 



at middle, disk -uneven with lateral and median depres- 

 sions minuta, new species 



More broadly oblong, prothorax with lateral sides arcuate and 

 disk more smoothly convex with only slight depressions. __ 9 



9. Aedeagus unusually long, elytra finely and shallowly punctate; 



southeastern Texas obesula, new species 



Aedeagus not unusually long, elytra rather coarsely and dis- 

 tinctly punctate; Colorado, Idaho. pallida, new species 



10. Aedeagus very broadly rounded, almost truncate at apex when 



viewed from above elegans, new species 



Aedeagus more or less tapering, sometimes acute at apex when 



viewed from above H 



11. Medium sized (3 to 4 mm.), with rather scant, short pubescence 



or with fine, silken pubescence, not deeply punctate 12 



Larger (3.5 to 5 mm.), conspicuously pubescent and coarsely 



punctate 14 



12. Elytra without long intrahumeral sulcus, with scant, short 



pubescence and finely punctate, somewhat shining; feeding 



on Gutierrezia puberula, new species 



Elytra sometimes with a long intrahumeral sulcus, either covered 

 with a fine silken pubescence or not shining but distinctly 

 punctate 13 



13. Elytra depressed, with a conspicuous deep intrahumeral sulcus, 



not densely pubescent, punctation quite visible and dis- 

 tinct - consputa LeConte 



Elytra not depressed, with a shallow intrahumeral sulcus, elytral 

 punctation somewhat concealed by fine, dense pubescence; 

 Lower Cahfornia beebei Blake 



14. Elytra with a long intrahumeral sulcus, pubescence long and 



not closely appressed but erectish; vicinity of San Francisco, 



feeding on Artemisia guttulata LeConte 



Elytra with only a short intrahumeral sulcus, pubescence closely 



appressed 15 



15. Elytra shallowly and very densely punctate, aedeagus viewed 



from above rather abruptly contracted into a somewhat blunt, 



wedge-shaped apex ; feeding on Grindelia inornata, new species 



Elytra deeply and more coarsely punctate, aedeagus usually 



longer and gradually narrowed at apex 1" 



