The most destructive species is the plum curculio, Conotrachelus 
nenuphar (Herbst.), which breeds in plum, cherries, peaches, 
apples, and other fruits. Adults are dark colored, have two promi- 
nent tubercles on the back, and are about 8 mm. long. 
Three acorn-infesting species occur in the United States: Con- 
panes naso LeC., C. posticatus Bohemian, and C. carinifer 
asey. 
Conotrachelus naso LeC. occurs from Maine to Florida and 
west to Minnesota in eastern United States. It has been bred 
from acorns of 16 species of oaks. The adult is shiny black to 
light reddish-brown, and from 4.8 to 6.6 mm. long. The beak is 
moderately stout and curved, and slightly longer and less stout 
in the female than in the male. Adults emerge from April to 
August, depending on locality. Eggs apparently are deposited in 
damaged, cracked, sprouted, or previously infested acorns. The 
larvae become full-grown in 2 to 3 weeks. Then they vacate the 
nuts and enter the soil to pupate. New adults emerge about 114 
to 8 months later. 
Conotrachelus posticatus Boheman occurs throughout much the 
Same range as C. naso. It is known to breed in acorns from nine 
species of oaks. The adults have dark, reddish-brown wings with 
black splotches, the black sometimes predominating, and their 
bodies are 414, to 5 mm. long. The beak is feebly curved, longer 
than the prothorax, and of the same length in both sexes. Adults 
emerge from June to August. The eggs, like those of C. naso, are 
deposited in damaged, cracked, sprouted, or previously infested 
acorns. The larval stage lasts 10 to 30 days. The first winter is 
spent as a larva in the soil; the second, as an adult beneath leaves 
on the ground. 
Conotrachelus carinifer Casey occurs in the Coastal States from 
New Jersey to Texas and west to Arizona. It has been reared 
from the acorns of eight species of oaks. The wing covers are 
dark reddish-brown with a few black areas, and the prothorax is 
black. The beak is curved in both sexes. Adults emerge in late - 
summer or early fall and begin laying eggs within 4 days. The 
larvae become mature and vacate the acorns within 12 to 18 days. 
Other common eastern species of Conotrachelus include (1) 
C. juglandis Le.C.—breeds in butternuts; (2) C. retentus (Say) 
—breeds in walnuts; (3) C. hicoriae Schoof and C. affinis Boh.— 
breed in hickory nuts; (4) the quince curculio, C. crataegi Walsh— 
breeds in the fruit of hawthorn; (5) C. aratus (Germ)—feeds on 
the young shoots and leaf petioles of hickory; and (6) C. anaglyp- 
ticus (Say—breeds in the tissues around fresh wounds on various 
deciduous trees such as hickory, birch, beech, maple, chestnut, 
and oak (105). 
FAMILY SCOLYTIDAE 
BARK BEETLES 
The family Scolytidae comprises three groups: (a) the true 
bark beetles which mine between the bark and wood, usually 
engraving both, of the twigs, branches, trunk, and roots of vari- 
ous trees; (b) wood-boring bark beetles which mine directly into 
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