willow. The adult is brown and about 2.7 mm long. The terminal hook of the 
anterior tibia is strongly curved. M. suturalis LeConte breeds in the twigs and small 
branches of redbud, walnut, and willow. 
The genus Micracisella includes certain species formerly included in the genus 
Micracis (123). Female adults have the antennal scape flattened, somewhat ex- 
tended laterally, and clothed with long hairs. 
Micracisella opacicollis (LeConte) occurs from Minnesota and New York to 
North Carolina. It breeds in the pith of dead twigs, in sprouts, and in shoots of oak, 
maple, redbud, and baldcypress. The adult is dark brown to black and from 1.7 to 
1.9 mm long. M. nanula (LeConte) breeds in oaks and redbud from South Carolina 
to Florida and Texas. 
The genus Thysanoes is closely allied to the genera Hylocurus, Micracis, and 
Micracisella, but differs in having the apex of the elytra broadly rounded. 7. 
fimbricornis LeConte breeds in the twigs of red and black oaks, maple, redbud, 
hornbeam, hackberry, hickory, and acacia from Pennsylvania to Florida and Texas. 
The adult is yellowish brown and from 1.6 to 1.9 mm long. Egg galleries are 
constructed almost entirely in the sapwood, nearly encircling the twig in a diagonal 
direction just beneath the bark. Larval galleries run parallel with the grain. The 
related species, 7. lobdelli Blackman, has been observed breeding in oaks and 
maple in Mississippi, Florida, and Georgia, and 7. berchemiae Blackman, in elm, 
oaks, and rattan-vine from Virginia to Florida and Texas. 
The genus Hylocurus contains a number of species that rear their brood in the 
wood of their hosts. In attacking the host, the adults bore directly into the sapwood 
or pith, where they construct nuptial chambers. From each chamber, one to several 
egg galleries are then extended obliquely through the wood or in several directions 
through the pith. The majority of species are of minor importance since they 
normally breed in recently cut, dying, or dead limbs of their hosts. Adults are quite 
small, 3 mm or less in length. The head is concealed from above by the pronotum, 
which is strongly roughened in front; the first joint of the antennae is club-shaped; 
and the elytra are elongated and pointed at the apex. 
Aylocurus rudis (LeConte) breeds in the twigs and branches of hickory, walnut, 
maple, and hackberry throughout much of the Eastern United States. The adult is 
dark brown to black and 2.2 to 3.0 mm long. H. spadix Blackman, H. biorbis 
(Blackman), H. bicornus (Blackman), and H. harnedi (Blackman) breed in hickory. 
Hylocurus langstoni (Blackman) occurs in the South from the East Coast to 
Texas. It breeds in the limbs and trunks of dying or recently killed honeylocust, 
hackberry, mulberry, and slippery elm. Green poles and posts are also frequently 
attacked and damaged. The damage resembles that caused by powderpost beetles. 
The genus Hypothenemus contains numerous species that breed in dying and 
dead twigs, dead bark, seeds, and hulls. Included in the genus are species formerly 
assigned to the genus Stephanoderes. A few of the seed-infesting species may be 
injurious at times. 
Hypothenemus dissimilis (Zimmermann) 1s widely distributed in eastern America 
from Quebec to Florida and west to Michigan. It breeds in dying branches and dead 
twigs of various hardwoods such as the hickories, oaks, honeylocust, hornbeam, 
and redbud. The adult is dark brown to black and from 1.2 to 1.8 mm long. They 
bore deep entrance holes, and one or more elongate tunnels are constructed more or 
less parallel to the grain. They may be found in the sapwood just beneath the bark, 
deep in the sapwood, or in the pith. Where numerous, they may honeycomb the 
wood. 
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