BEETLES OF THE GENUS MYOCHROUS — BLAKE H 



6. From 3.5 to 5 mm. in length ; aedeagus with a not very acute tip 



(San Joaquin "Valley, Calif.) whitei, new species 



From 4.5 to 5.5 mm. in length ; aedeagus with a fine acute tip 



(southern California, Arizona, Colorado, Idaho) longulus LeConte 



7. Body reddish brown or coppery, covered by yellowish or pale brown- 



ish scales, sometimes mixed with darker brown 8 



Deep piceous, often with bronzy luster, covered by grayish scales 

 mixed with darker brown ones 11 



8. Large, G to 8 mm. in length, unusually finely punctate, often having 



a median depression on anterior edge of prothorax (Browns- 

 ville, Tex., and along lower Mississippi; Mexico) magnus Schaeffer 



Smaller, 4 to G mm. in length 9 



9. Prothorax almost as long as wide, uneven with depressions, scales 



very dense and curved, tip of aedeagus prolonged into a slender 



point (Iowa, South Dakota, Kansas, Missouri) movallus Johnson 



Prothorax distinctly wider than long, without depressions 10 



10. Deep reddish brown, prothorax very rugose, with deep, coarse 



punctures and with no depressions except along basal margin 



(Virginia to Florida and west to Louisiana) floridanus Schaeffer 



Not quite so large and with less rugose prothorax, punctures not so 

 coarse and distinct; aedeagus with a sharper tip (Columbia, 

 Tex.) floridanus texanus, new subspecies 



11. Prothorax large, approximately as wide as elytra, pinched in con- 



spicuously behind eyes and depressed along basal margin ; beetle 

 relatively short and broad (Virginia southward and along Gulf 



to Louisiana) ranella, new species 



Prothorax not so heavy and not conspicuously pinched in behind 

 eyes ; beetle more slenderly oblong 12 



12. Scales on elytra rather fine and not so dense as to hide punctation 



below ; prothorax without any pronounced median convexity 

 (Mississippi Valley from Iowa to northern Texas, and from Mary- 

 land to Georgia and along Gulf coast) denticollis (Say) 



Scales on elytra dense ; prothorax with a median convexity 13 



13. Elytral scales curved, not appressed ; prothorax coarsely punctate 



(Arizona) austrinus, new species 



Elytral scales appressed, prothorax very finely punctate (southern 



Texas, New Mexico, Mexico) cyphus, new species 



MEXICO AND CENTRAL AMERICA 



1. Deep reddish brown or coppery brown 2 



Piceous or black, usually with a bronzy luster 4 



2. Thorax very densely and finely punctate, covered with dense yellow- 



ish scales (southern Texas and area below Brownsville in Mexico, 



and along lower Mississippi) magnus Schaeffer 



Thorax not very densely or very finely punctate 3 



3. Large, 7 to 8 mm., covered with short white scales (Mexico) sallei Baly 



Smaller, 5 to 7 mm., covered by yellowish or pale brownish scales 



(Mexico, Guatemala, Honduras, Nicaragua, Panama) tibialis Jacoby 



4. Small, 4.5 to 5 mm., aedeagus pale with a fine dark line down middle 



of tip (Panama) elachius, new species 



Larger, 5 to 6 mm 5 



5. Aedeagus with a hollowed-out scooplike tip (Panama, Colombia). 



platylonchus, new species 

 Aedeagus not scoop-shaped at tip G 



