1. Hypomeron with margin of pronotosternal suture deeply channeled
along length to receive antenna. . . . . . . . . . . . . . . . . . 2
Hypomeron with margin of pronotosternal suture not
channeled, at most briefly excavate or reflexed anteriorly. . . . . . .
. . 4
2. Scutellum carinate along midline; size small, 3.0 mm long;
dorsal pubescence of sparsely distributed erect and squamiform
setae. . . . . . . . . . . . . . . . . . . . . .
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
. . . . . . . . . . . . . . . . . . . . . . .Rismethus
Scutellum flat to shallowly convex, lacking median
carina; size larger, greater than 5.0 mm long; dorsal pubescence
moderately dense, appressed, thick hair like setae.
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
. . . . . . . . . . . . . . . . . . 3
3. Hypomeron and metasternum with deep, oblique channels for
reception of tarsi; body short, ovoid . . . . . . . . .Brachylacon
Hypomeron and metasternum lacking deep channels,
shallowly impressed at most; body elongate, 11-15 mm long. . .Lacon
4. Hypomeron reflexed and briefly channeled anteriorly along
pronotosternal suture. . . . . . . . . . . . . . . . . . . . . . . . .
. . . . . . . 5
Hypomeron not reflexed or channeled along pronotosternal
suture . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
. . . . . . . . . . .6
5. Size large, 20 mm or longer; pronotum depressed discally and
explanate laterally; claws with 3-5 large ventral setae. . . . . .
. . . . . . . . . . . . . . . . . . . . . . . .
. . . . . . . . . . . . . . .. . . . . . . . . . . . . . . . . . . . .
. . . . . . . . . . . . . . . . . . . . . Chalcolepidius
Size smaller, less than 7.0 mm long; pronotum evenly
convex, with narrow lateral margin; claws asetose. . . . . . . Anchastus
6. Scutellum cordate, emarginate along anterior margin; pronotum
with lateral margin ecarinate; claws dentate at midlength. . .
. . . . . . . . . . . . . . . . . . . . . . . .
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
. . . . . . . . . . . . . . . . . . . . . . .Dicronychus
Scutellum subtriangular, anterior margin truncate;
pronotum with carinate lateral margin; claws slender, edentate . . . .
. . . . .7
7. Elytron with striae subparallel to apex; claws with 1-2 fine
setae set ventrolaterally. . . . . . . . . . . . . . . . . . . . . . .
. . . . . . . . 8
Elytron with striae convergent and coalescent before
apex; claws asetose. . . . . . . . . . . . . . . . . . . . . . . . . .
. . . . . . . . . . .11
8. Size larger, 9.0-18.0 mm; dorsum somber, uniformly colored,
at most with pronotal hind angles pallid; tarsomere 4 with
large membranous lobe. . . . . . . . . . . . . .
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
. . . . . . . . . . . . . . . . . . . . . . . . . 9
Size smaller, 3.5-9.5 mm; dorsum of pronotum and
elytra variegated with dark maculae; tarsomere 4 with short projecting
setal pad. . . . . . . . . . . . . . . . . . . .
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
. . . . . . . . . . . . . . . . . . . . . . . . . . . . .10
9. Pronotal punctures small to moderate in diameter, evenly
subequal on disc. . . . . . . . . . . . . . . . . . . . . . . . . . . .
. Conoderus
Pronotal punctures mixed small to large, distinctly
unequal on disc; interspaces usually microreticulate. . . . . . . . Heteroderes
10. Body 7.0-9.5 mm long; prosternal process planar; pronotum
depressed discally, hind angles sinuate laterally and divergent.
. . . . . . . . . . . . . . . . . .
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Aeolus
Body 3.5-5.0 mm long; prosternal process
arcuate; pronotum convex discally; hind angles subparallel. . . .
. Prodrasterius
11. Elytron attenuate, or truncate with apical angles spinose.
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
. . . . . . . . . . . . 12
Elytron with apex evenly rounded, not
spinose. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
. . . . . . . . . . . . . . . . . . . . . . . .13
12. Elytron with apex truncate, spinose on outer apical angle,
orange colored with black apex; head and pronotal disc black. .
. . . . . . . . . . . . . . .
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
. . . . . . . . . . . . . . . . . . . . . . . . . . . . Melanoxanthus
Elytron attenuate, apical spine medial
or sutural, variably colored, usually somber. . . . . . . . . . . . . .
. . . . . . . . . Eopenthes
13. Pronotal hind angles bicarinate; tarsomere 3 short, oblique
apically, with large divided setose lobe. . . . . . . .
Simodactylus
Pronotal hind angle unicarinate; tarsomere
3 filiform, lacking ventral lobe. . . . . . . . . . . . . . . . . . . .
. . . . . . . . . . . . . . . . .14
14. Metathoracic wing well developed, alate; body elongate. .
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
. . . . Itodacnus
Metathoracic wing absent, apterous;
body proportionately short and legs long. . . . . . . . . . . . . . . .
. . . . . . . . . . .Dacnitus