1. Head almost entirely protruding from the prothorax; 
mandible usually dentate; terga usually hairy or as- 
OCT ALC Reet wre NF Fin sub erin rs ys we mryieels | Beate re te 3 
Head deeply embedded in prothorax; cutting edge of man- 
dible gougelike, rarely toothed; terga never asperate... 2 
2. Last abdominal spiracle much larger than all others; 
mandible with a fleshy process on dorsal inner edge 
Lyctus 
Last abdominal spiracle not abnormally large; mandible 
with or without fleshy lobe oo... Bostrichidae 12 
3. First spiracle pushed forward into anterior margin of 
prothorax; terga without asperities; usually found in 
stored plant material, seed, ete. oie Ptinus 
First spiracle between prothorax and mesothorax; terga 
usually asperate 
4. Chitinization between labium and mentum narrow and 
Ueshapedror lacking; mala divided 0... 5 
Chitinization arrow-shaped and pointing posteriorly ; mala 
simple, no inner lobe; spiracles large, annular without 
spoutlike projection from COTO (teas am ce a a ce Ptilinus 
5. Inner lobe of mala consisting of a strong, curved spine 
Xestobium 
Inner lobe of mala fleshy, usually with several smaller 
GINS Ole SCCACE 2S. Moma mna ere ten edit Willey Ue 6 
6. Inner lobe of mala smaller than outer. Spiracles with a 
short or Jone. “spoutlike: process: 2. ee ql 
Inner lobe of mala about as large as outer; spiracles with 
a Short spouthike process]. Sac se a ee 9 
7. Claw short and curved; a fleshy lobe at base; feeding in 
stored plant products and Seeds ......................... Lasioderma 
Claw usually slender, no lobe; wood borers ................................ 8 
8. Spiracles with long spoutlike process; mandible with 3 
lateral teeth on dorsal edge 20. Anobium 
Spoutlike process on spiracles only indicated; each side 
of prothorax curved rodlike impression. Mandible with 
Selavetalecectnc Tee ane Hemicoelus 
Mandible with 2 lateral teeth ...................... Microbregma 
9. Labrum about twice as wide as long .. Ernobius 
abtum about, as: wide as, lON@ oct eed 10 
10. Tergal asperities in about 2 transverse rows... Xyletinus 
Tergal asperities in about 4 transverse rowS |... 11 
11. Posterior tergal fold with long, soft hairs .......... Nicobium 
Posterior tergal fold densely beset with short, spine- 
NIRS ag Settee wey DON Walaa ius bade iid, rio oa de ht le ne Trichodesma 
12. Mandible with a large, grinding lobe and a soft, fleshy 
lobe on upper inner margin; no impressed line on side 
of prothorax; tarsi all bearing chitinized claws... 18 
Mandible without chitinous or fleshy lobe; a curved im- 
pressed line on side of prothorax, usually only first 
Fansalenclaw: 2c Mitinl ZC Gea eee Ahan: Wied waren each ho 16 
18. Prothorax bearing a chitinized tubercle in front of spir- 
acle; no ocelli; cutting edge of mandible entire 14 
No tubercle : ocelli present; cutting edge of mandible 
Gdentatetinvi st: a seen Siva SU te 135" TA Teme ne 15 
AY 
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