Leaf Beetles

of the cerambycids. They are mostly black or brown, usually with a metallic luster, and range from 5.5 to 12.0 mm. Larvae feed in submerged parts of aquatic plants; adults are found on flowers and foliage of water lilies and other aquatic plants, and are active, fast-flying, often difficult to capture.

Flea Beetles, Subfamily Alticinae. Flea beetles are mostly 2-5 mm., black or bluish (sometimes with light markings) and with enlarged hind femora; antennae are close together at the base and front coxae are usually conical. The common name refers to their jumping habits. Some flea beetles are important pests of various cultivated plants; larvae feed in roots of the host plant and adults feed on the leaves. Adult feeding produces holes in the leaves. A heavily infested plant looks as if tiny shot had been fired into the leaves.

Subfamily Criocerinae (see also PL 8). These have the pro-notum rounded (its base narrower than base of FW, or elytra), the punctures of the elytra are in rows, and the head is prominent and narrowed posteriorly. The group is small, but contains some important crop pests: Crioceris (2 species) attacks asparagus, Lema trilineata (Olivier) attacks potatoes, and Oulema melanopus (Linn.), the Cereal Leaf Beetle, attacks grains.

Subfamily Chrysomelinae (see also Pl. 8). Most members of this group are oval to nearly circular, very convex, often brightly colored, and have the head sunk in the pro thorax almost to the eyes; antennae are widely separated at base, and pronotum is margined laterally. Most species feed on various weeds and are of little economic importance. The best-known and most important species is the Colorado Potato Beetle, Leptinotarsa decemlineata (Say), a serious pest of potatoes; it is large, orange-yellow, and has longitudinal black stripes on the elytra.

SEED BEETLES Family Bruchidae

Identification: Shape distinctive: body oval or egg-shaped, broadest posteriorly; head concealed from above, prolonged into a short broad snout. Antennae clubbed or serrate, sometimes pectinate. Black or brown, often mottled or marked with patches of whitish or brownish pubescence. Elytra (FW) short, exposing tip of abdomen. 1-10 mm. Similar to Chrysomelidae (p. 198), although differing in body shape and in having a snout.

Seed beetles are usually found on foliage, or in stored peas, beans, or other seeds; larvae of most species feed inside seeds, and some seriously damage beans or peas. The Bean Weevil, Acanthoscelides obtectus (Say), attacks beans in storage or in the field and may completely destroy them; in a heavy infestation, as many as a dozen beetles may develop in a single bean. The Pea Weevil, Bruchus pisorum (Linn.), attacks peas in the field; larvae consume the central portion of the pea.

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