The black twig borer, X. compactus (Eichhoff), introduced from southeast 
Asia, was first detected in Florida and Cuba in 1941. It has invaded Georgia, 
Mississippi, and Louisiana, and will probably spread throughout much of the 
Southeastern United States. Vigorous terminal twigs of more than 200 known host 
species are attacked and killed. Hosts include maples, hickories, magnolias, oaks, 
willows, and many others. This aggressive species is a serious pest in deciduous 
forests and in horticultural areas. In Florida, smaller twigs (1 to 7 mm in diameter) 
of dogwood were infested by single females, and larger twigs contained several 
females (927). 
Xylosandrus morigerus (Blandford), the red shothole borer, was introduced 
from southeast Asia, and has spread from Mexico to Brazil. It has been intercepted 
at several ports of entry in the United States but it has not yet become established. It 
breeds in broken or cut branches about | to 3 cm in diameter (/356). 
Xylosandrus crassiusculus (Motschulsky), also from southeast Asia, was found 
near Charleston, S.C., in 1975 on cherry. Its galleries resemble those of Xyleborus 
dispar (F.) (1356). 
Family Platypodidae 
Platypodid Beetles 
Almost all members of this family are ambrosia beetles and they occur prin- 
cipally in the tropics and subtropics. Only one genus has been recorded from the 
United States (J355). The adults differ from those of other ambrosia beetles in 
having longer and more slender bodies and wide heads flattened in front, not 
covered by the pronotum. The first segment of the tarsus 1s as long as the other three 
tarsal segments combined, and there are spinelike projections at the seam of the 
elytra of the males (20/). 
Members of the family are usually more destructive than other ambrosia beetles. 
Their tunnels are more extensive, and they extend deeper (25 to 30 cm) into the 
sapwood and heartwood. Dying, weakened, or recently felled trees are usually 
preferred; however, vigorous, healthy trees are also attacked if dead areas of bark 
are present. Eggs are laid in small loose clusters in the tunnels. Larvae and adults 
are also found in these tunnels. 
Platypus flavicornis (F.) occurs in the Eastern United States from New Jersey to 
Florida and west to Texas and Mexico. It breeds commonly in various species of 
pines and occasionally in several species of hardwoods. Dead and dying trees, 
stumps, and logs cut or left in the woods during the summer are preferred. It is 
commonly found in the lower | m of trees killed by southern pine beetle (245). 
Adults are reddish brown and about 5 mm long. The front of the head is flat and 
clothed with moderately long hairs; the pronotum is longer than broad and densely 
but shallowly punctured; and the elytra are elongate and striate, with the third, fifth, 
seventh, and ninth interspaces produced into blunt, toothlike processes on the 
declivity of the male. The adult bores a horizontal gallery in the sapwood (fig. 174). 
Here, it may branch extensively and extend into the heartwood. The lower portions 
of infested trees are sometimes literally riddled. In the South, this species is so 
abundant that very few dying pines, stumps, or logs escape attack. Large amounts 
of white downy frass is evidence of attack (76). 
Platypus quadridentatus (Olivier) occurs throughout the South from Florida to 
Texas and north to West Virginia. Various species of hardwoods, especially the 
oaks, are most commonly attacked. Adults are dark reddish brown and about 4.5 
mm long. The front of the head is shallowly and densely punctured and sparsely 
clothed with moderately long hairs. The pronotum is longer than broad, and in the 
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