Leaf-eating insects can become serious pests. However, it's usually the larvae of the insects that do the damage. Insects that continue to eat leaves even after they've become adults include scarabs and other species of beetles. Other adult insects feed on plant nectar, sap, fruit, grains, flowers and other, smaller insects.
The 10 lined chafer is a .98-inch-long beetle from the scarab family. It feeds on pine needles and is found in the western United States. Like a lot of scarabs, it has horns on its head and thorax, but they are not for combat. Scarabs use their horns to flip their rivals on their back. If they're on a tree branch, they'll use the horns to flip them over the edge.
The spotted June beetle is .79 to .98 inches long and is a dull yellow brown with spots of darker brown. The adults eat grape leaves and are found in the eastern United States. They are attracted to porch lights.
The glorious beetle, an endangered species, eats juniper leaves. It grows from .98 to 1 inch long and is bright green with silver stripes on its wing covers. Its habitat ranges from Texas to Arizona to Northern Mexico.
Bear beetles are members of the paracotalpa genus and feed on the leaves of several plants. Paracotalpa ursina, one type of bear beetle, likes the plants of the rose family, while paracotalpa granicollis, a type of hairy bear beetle, likes to eat the leaves of peach trees. They're named bear beetles because they're round and fuzzy, like bears. They will grow to between .5 and .69 inches long and live on the West Coast of the United States.
The Godson's leaf beetle only eats the epidermis of the leaves of the day flower. It is bright scarlet with black spots on the wing covers. It has a longish back, curving antennae and strange, weevil-like legs and feet. Its habitat ranges from Arizona to Guatemala.
The Colorado potato beetle is .22 to .43 inches long. The round beetle can range in colour from dull yellow to orange red. Another species in this genus, the leptinotarsa, eat only the leaves of potato relatives. Another species, the leptinotarsa juncta, eats horse nettle.
The cottonwood leaf beetle is an oval beetle, .22 to .35 inches long, that eats the leaves of willow and poplar. Some member of this genus chrysomela are restricted to feeding on just one type of tree.
The spotted cucumber beetle, .24 to .3 inches long, is greenish yellow and has black spots. The adults feed on the foliage of cucumbers, corn and other plants. It lives in eastern North America to Colorado and Arizona.
The Japanese beetle is a scarab that will grow between .7 and 1.1 inches long. It is a metallic blue colour with reddish brown or coppery wing coverings, and the abdomen has patches of little white hairs. The beetle was imported from Asia in 1913. The adults, which emerge in midsummer and early fall, feed not only on the leaves but also on the flowers of plants of the rose family. The Japanese beetle has become an extraordinarily destructive pest.
- "Simon and Schusters Guide to Insects"; Dr. Ross H. Arnett Jr., et al.;1987
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