Other common eastern species of Pseudopityophthorus are: P. pruinosus 
(Eichhoff)—breeds primarily in dead and dying oaks; also in beech, American 
hornbeam, hickory, maple, and hophornbeam. Smooth-barked branches in the 
upper parts of standing trees are preferred, but slash and other recently felled 
material also are attacked. The adult is dark brown and about 1.5 to 1.8 mm long. 
This species also is suspected of transmitting oak wilt fungus (/023). P. pubescens 
Blackman—breeds in various oaks, American hornbeam, and chestnut in the 
Southeast. The adult is dark brown, about 1.8 mm long, and the male has rows of 
very long hairs on the elytra. P. asperulus (LeConte)—breeds in various species of 
oaks, chestnut, and gray birch from Maine to Florida and Texas. The adult is dark 
reddish-brown and from | to 1.5 mm long. 
The genus Cryphalus consists of small, dull, dark-brown to black beetles about 2 
mm or less in length. They usually breed in small, suppressed trees but may also be 
in twigs, branches, and seedlings. C. fraseri Hopkins attacks Fraser fir in the 
Southern Appalachians and balsam fir throughout the Northeastern States and in 
eastern Canada. C. ruficollis Hopkins is found commonly in red and white spruces 
in Maine and New York. C. rubentis Hopkins has been collected from red spruce in 
West Virginia. 
The genus Pityophthorus is represented by more than 100 species in North 
America, many of which occur in eastern forests. The majority of species breed in 
the inner bark and central pith of twigs or small branches, but a few may be found 
in larger material. Most species utilize conifers, especially pines; a few species 
attack broadleaf trees. 3 
Gallery systems usually consist of 2 to 4 egg tunnels radiating from a central 
nuptial chamber, although the pith-feeding species construct an unbranched system. 
All species deposit eggs individually in niches. Material colonized by 
Pityophthorus is usually unthrifty, cut or broken, except that certain pith-feeding 
species may bore into healthy twigs. 
Despite its pervasiveness, this group of insects causes little economic injury 
except killing of twigs on drought-stressed saplings, and infesting scions on special 
grafted planting stock. 
Adults are very small (1.3 to 2.0 mm long), shiny, and have a distinct elytral 
declivity that may be armed with tiny spines. Females usually have a frontal brush 
of yellow hairs while males do rot (//5, 1/6). Identification of species in this 
difficult genus is usually a task for experts. Detailed information on Pityophthorus 
can be found in a generic revision (/54) or in a monograph on the North American 
Scolytidae (1356). 
Pityophthorus lautus Eichhoff breeds in redbud, sumac, and a variety of other 
hosts from Minnesota and Quebec to Missouri and North Carolina. P. liqguidam- 
barus Blackman breeds in sweetgum, probably throughout the natural range of this 
tree. P. crinalis Blackman breeds in poison-sumac and P. scriptor Blackman breeds 
in staghorn sumac. 
Pityophthorus pulicarius (Zimmermann) occurs throughout the Eastern United 
States and in eastern Canada. It attacks all species of pines in its range and has also 
been recorded from deodar cedar. Infestations occur in the wood and pith of twigs 
of dead and dying trees, in small trees scorched by fire, in slash, and in |-year-old 
cones of felled pines. Scions of grafted slash pines being prepared for seed orchard 
establishment in Florida have been seriously injured. 
Additional eastern species of Pityophthorus and their hosts are as follows: P. 
opaculus LeConte—eastern white pine, tamarack, balsam fir, and various spruces 
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