Combclawed Beetles

bark, in rotting wood, in fungi, or in vegetable detritus and are similar in appearance to wire worms.

FALSE DARKLING BEETLES Family Melandryidae

Identification: Elongate-oval. Nearly always dark-colored. Pronotum usually with 2 dents at base. Front coxal cavities open behind. 1st segment of hind tarsi longer than any other segment. Antennae generally threadlike. 3-20 mm.

Adults and larvae are found under bark, in dry wood, or in dry fungi; some adults are found on flowers and foliage. Larvae are carnivorous or plant-feeding. The most common eastern melandryids (genus Penthe) are elongate-oval, black with black pubescence, and 10-14 mm.

Superfamily Bostrichoidea

Tarsi 5-5-5. Pronotum usually extending over and partly or completely concealing head from above. Generally small.

SPIDER BEETLES Family Ptinidae

Identification: Shape distinctive: spiderlike, FW elongate-oval, pronotum narrower than FW and nearly or completely concealing head from above, legs long and slender. FW usually dull and with erect pubescence, sometimes shiny and not pubescent. Reddish brown to black. Antennae long, threadlike. 1-5 mm.

Adults and larvae of this small family are found in various dried animal and plant materials, such as animal carcasses, animal droppings, dry wood, stored products, and in museum specimens of plants and animals. Some species live in ant nests. Spider beetles are not common.

DEATH-WATCH BEETLES Family Anobiidae

Identification: Pronotum hoodlike, usually enclosing head and concealing it from above. Antennae nearly always with last 3 segments lengthened and expanded, or simply lengthened, sometimes serrate or pectinate, rarely threadlike. Shape variable, usually elongate and cylindrical, sometimes oval to nearly spherical. Appendages often contractile. Hind coxae grooved for reception of femora. Light brown to black. 1.1-9.0 mm.

Nearly all anobiids feed exclusively on plant materials as larvae and adults. Many bore into seasoned wood; some are found indoors after having emerged from furniture, woodwork, flooring, or timbers. Some species produce a ticking sound in their burrows. Superstitious people, thinking this a portent of death, have called these insects "death-watch" beetles. Some live under bark, others in fungi, and some in seeds and galls. Two species, the Drugstore Beetle, Stegobium paniceum (Linn.), and the Tobacco Beetle, Lasioderma serricorne (Fabricius), are

BRANCH AND TWIG BORERS 189

serious pests of stored products. Both feed on a wide variety of materials of plant and animal origin, and are among the very few anobiids that feed on materials of animal origin.

Most anobiids are infrequently collected. The greatest number and variety, at least in the East, can be taken by sweeping or beating foliage in wooded areas where the overhead canopy is dense. Examine the catch closely or you will overlook them, since many draw in the appendages and play dead when disturbed.

BRANCH and TWIG BORERS Family Bostrichidae Identification: Form distinctive: broadly to narrowly cylindrical, head bent down and appearing on ventral surface of pro-thorax, nearly or completely concealed from above; pronotum usually tuberculate or with rasplike teeth anteriorly, not hoodlike

Side view of Hemicoelus

Dorcatoma

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