Several species of western origin may be shipped to the Eastern States in infested 
wood. Polycaon stouti (LeConte) is commonly encountered. Its appearance 1s 
unlike other bostrichids in that the head is visible and the pronotum is not hoodlike. 
The pronotum and elytra lack tuberculate projections. The subcylindrical body is 
coal black and from !2 to 25 mm long. 
Family Ptinidae 
Spider Beetles 
The common name for this family appropriately describes the appearance of 
these beetles. Adults are 2 to 4.5 mm in length. The head and pronotum are much 
narrower than the abdomen, the legs are long, the antennae are long and filiform, 
and the elytra are usually very convex and shiny. The majority of species breed in 
old grass roots or in dead bark. The brown spider beetle, Ptinus clavipes Panzer, 
and the whitemarked spider beetle, P. fur (L.), occasionally damage pine boards 
in old buildings. Both are cosmopolitan species that frequently damage dried 
vegetable and animal products in warehouses and museums. Gibbium psylloides 
(Czenpinski) occasionally is a pest in attics of houses where organic matter has 
accumulated. 
Family Bruchidae 
Seed Beetles 
Members of the family Bruchidae are distinguished by their compact and usually 
oval bodies. Their small heads are prolonged into beaks, and their short wing 
covers leave the top of the abdomen exposed. The larvae are quite small and feed 
almost entirely in the seeds of plants. 
Amblycerus robiniae (F.) is occasionally a pest in the Eastern United States. The 
female deposits her eggs on the pods of honeylocust and the larvae feed on the seeds 
within the pod. Adults are reddish brown and about 7 mm long. The body is clothed 
with grayish-yellow hairs and there are five rows of black spots across the elytra. 
Gibbobruchus mimus (Say) breeds in the seeds of the redbud and Caryobruchus 
gleditsiae (L.), in palmetto. 
Family Chrysomelidae 
Leaf Beetles 
Leaf beetles are one of the larger families of Coleoptera, with about 2,000 
species occurring in North America. The adults usually are medium size or small, 
short-bodied, and more or less oval. The legs are generally short, but in some 
species the femora of the hind pair are enlarged. There is great variation in coloring 
and markings, occasionally even within a species. In some species the entire body, 
elytra, and legs may have a bright metallic sheen. Some are hairless; others are 
pubescent or covered with scales or scalelike hairs. 
Leaf beetle larvae are usually soft-bodied and frequently have highly pigmented 
sclerites. They vary greatly in shape, depending on their feeding habits. The head 
usually protrudes, except in the leafminers, and is bent downward for feeding. The 
body varies greatly in shape, from short and compact to depressed cuneiform, 
depending on whether the larva is free-living or a leafminer, casebearer, or root 
feeder. 
All members of the family feed on the foliage of plants as adults or larvae, or 
both. The adults are diurnal and are usually slow moving. Species that are exposed 
in the larval stage feed gregariously, whereas leafmining larvae usually feed singly, 
each within its own mine. Adult feeding is characterized by the presence of holes 
eaten all the way through the leaf, or by skeletonization usually of the lower surface 
of the leaf. Free-living larvae either fasten themselves to the surface of the leaf to 
pupate, or move to the ground to do so. Leafmining larvae pupate either within the 
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