Family Colydiidae 
Colydiids 
Members of this family vary in form and habit. They are hard-bodied, shiny, 
often beautifully sculptured, and reddish brown to nearly black. Many species are 
elongate, cylindrical, and rarely more than 5 mm long, but some larger species are 
strongly flattened and oval. Larvae of the latter are more robust in form and usually 
are found as scavengers in bark beetle galleries. Larvae of other species— 
Nematidium filiforme LeConte, Bitoma carinata (LeConte), and Colydium lineola 
Say—are elongate, slender forms that prey on larvae of ambrosia beetles, cossonid 
weevils, and some other wood borers. Other species are phytophagous and live on 
fungi or decaying vegetation. 
Family Melandryidae 
Melandryids 
Adults of this family are 2 to 15 mm in length, and they are usually elongate to 
oval, loosely jointed beetles. Their antennae are 11-segmented and filiform; their 
color is dark brown to black. Adults are seldom seen, but the larvae occur 
commonly under the bark on dry, decaying logs or in dry fungi. 
Some of the more common species and places to expect them are: Melandrya 
striata Say—many different hardwoods in association with black lines of decay; 
Orchesia castanea Melsheimer—oak, maple, yellow-poplar, sycamore, and 
hickory; Hypulus concolor (LeConte)—rotting pine sapwood; Serropalpus sub- 
striatus Haldeman and Eustrophus tomentosus Say—various conifers; and Dircaea 
quadrimaculata (Say) and Holostrophus bifasciatus (Say)—various hardwoods. 
Family Oedemeridae 
Oedemerid Beetles 
Adults are usually elongate and subcylindrical with elytra soft in texture and 
sometimes covered with fine silken hair. Their color varies from pale to black, often 
with red, yellow, or orange markings. They range in length from 5 to 20 mm. The 
next-to-last tarsal segment is dilated and bears a dense, hairy pad beneath. Not 
much is known of the habits or habitats of the 68 species in the United States. 
Adults commonly visit flowers to feed on nectar, sometimes pollen, and they are 
attracted to lights. The larvae feed in damp, decaying wood. 
The wharf borer, Nacerdes melanura (L.), 1s cosmopolitan and occurs on most 
coastlines and around the Great Lakes (33/). Adults are reddish yellow with a dark 
patch on the head, two dark patches on the thorax, and blackened tips on the elytra. 
Larvae of this species, the only economically important member of the family, 
occasionally are very destructive to moist wood poles, pilings, boardwalks, or 
basement timbers (885). Adults are present from April to July in outdoor infesta- 
tions, but they may emerge at other times within buildings. 
Family Tenebrionidae 
Darkling Beetles 
Many species of this large family occur in the forest. The adults are hard-shelled, 
usually dark brown or black, 3 to 20 mm in length. Many are clumsy and slow- 
moving. The larvae are long and slender, and are often covered with tough, horny 
skins. The majority of forest species feed as scavengers on dead vegetable matter 
and fungi. They are commonly found under the bark of dead and dying trees or 
decaying logs, and occasionally in the galleries of bark beetles. A few species in the 
genus Strongylium bore into the wood of living trees at stubs or wounds. 
Family Lymexylonidae 
Timber Beetles 
Two species of timber beetles are known from the Eastern United States. Adults 
are slender and elongate; the head is deflexed and narrowed behind the large eyes to 
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