14. Inner edge of molar lobe of mandible smooth 
Polycaon 
15. Six ocelli; breeds in conifers ..........00ccc0.0. Stephanopachys 
Breedsiine- bamboo tere ee eee Dinoderus 
16. Maxillary mala without projecting style or spine on 
inner edveslabrunitcilobede = eee eee ILS 
Maxillary mala with a free projecting style or spine on 
inner edges labrum entire. eee 18 
17. Chitinization of labium broken in middle; prothoracic 
spiracle larger than antennal ring 
Dendrobiella; Xylobiops 
Chitinization of labium continuous across middle; pro- 
thoracic=spinacle’smialilerea..) .. ee ee _ Scobicia 
18. Spiracle with a spoutlike process; style shorter than 
LACTNITA: Sse) ee Re eee We can oem. are Lichenophanes 
Spiracles without process; style longer than lacinia 
Amphicerus 
FAMILY LYCTIDAE 
POWDER-POST BEETLES 
This family contains the most injurious of the powder-post 
beetles occurring in North America. According to some authori- 
ties their destructiveness to wood and wood products is exceeded 
only by that of termites. The family has been revised by Gerberg. 
Keys to all 12 genera in the world and to all 35 species in the new 
world were also published (285). 
Lyctid beetles are small, slender, elongate, reddish-brown to 
black, and about 5 to 6 mm. long. The head is prominent, slightly 
deflected, and constricted behind the eyes. Mature larvae vary in 
size but are usually less than 5 mm. long. The body is small, 
curved, and enlarged at the thorax. 
The larvae of North American species bore in the sapwood of 
seasoned hardwoods, making small tunnels up to 0.6 mm. in 
diameter. Second growth ash, hickory, and oak which has been 
seasoned and stored in the same place for 2 or more years are 
most seriously damaged. Many other hardwoods such as elm, 
maple, poplar, cherry, persimmon, sycamore, and walnut are also 
infested. Because starch is an important component of the larval 
diet, dry seasoned wood of high starch content is damaged most 
seriously. The same wood may be infested repeatedly, and the in- 
terior may be nearly reduced to powder, and rendered useless. 
Damage is common in stored lumber, the interior woodwork of 
buildings, furniture, tool handles, pallets, tent stakes, mallets, 
mauls, and many other stored hardwood products. This is par- 
ticularly true of wood that is left unfinished until it is placed on 
the market or in use. 
Lyctus spp. are attacked by several species of insect parasites 
and predators; however, they cannot be relied upon to keep these 
pests under control (671). The clerid, Tarsostenus univittatus 
(Rossi) is a common predator of both adults and larvae. Various 
species of predaceous mites also destroy large numbers at times. 
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