The Bugwood Network

Whitefringed Beetle- Graphognathus spp.

Dr. Steve L. Brown, Extension Entomologist, The University of Georgia, Department of Entomology, Tifton, GA 31793
Dr. Will Hudson, Extension Entomologist, The University of Georgia, Department of Entomology, Tifton, GA 31793

Order Coleoptera: Family Curculionidae

Description: Adults are dark gray beetles, about 12 mm long, with a broad, short snout. The margins of the elytra are banded with white. The elytra of adults are grown together so they cannot fly. Larvae are yellowish-white, legless grubs with brown heads. They are about 12 mm long.

Hosts: A wide variety of agronomic, horticultural and tree crops. Adults feed on more than 170 different plants. Larvae feed on the roots of at least 385 species of plants.

Damage: Adults feed on leaf margins, destroying foliage. As many as 300 have been found per plant. Larvae do the most serious damage, chewing away the lower part of the stem and taproot of hosts plants. Larval feeding causes plants to yellow, wilt and die. Larvae also attack planted seeds.

Life Cycle: Large larvae overwinter in the upper foot of soil. They pupate from late May through July. Adults are active from early May until mid-August. No males have been found. Females reproduce parthenogenetically. Egg-laying begins 10 to 12 days after females emerge. Each female crawls from plant to plant and lays hundreds of eggs (up to 3,200/female known) in gelatinous masses (of up to 60 eggs each) on objects on or near the ground. Eggs hatch in about two weeks. Emerging larvae feed below ground until cold weather, when they overwinter. There is one generation per year.

Whitefringed Beetle larva and damage
Photo by: James Solomon, USFS

Whitefringed beetle adult
Photo by: Gerald Lenhard, LSU

Control: Federal and state quarantines restrict the movement of untreated products likely to convey the beetles in any stage. Larval populations can be controlled by soil applications of insecticides before planting. Adults are easily killed by insecticides.

In: Roberts, P. M. and G. K. Douce, Coordinators. 1999. Soil Insects. A County Agent's Guide to Insects Important to Agriculture in Georgia. Univ. of GA, Col. Ag. Env. Sci., Coop. Ext. Serv., Tifton, GA USA. Winter School Top Fifty Agricultural Insect Pests and Their Damage Sessions, Rock Eagle 4-H Ctr., Jan. 20, 1999.

Selected References and Suggested Readings

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