WHITEFRINGED BEETLES: Graphognathus leucoloma, G. Fecundus, G. peregrinus, and G. minor, Curculionidae
ADULT: Small (7/16 in) grayish beetle with white markings along the outer edge of wing covers. Mouthparts are on a short, broad, truncated beak. The first antennal segment is long with the remaining segments held projecting frontward in a manner similar to ants . Wing covers are fused resulting in functionally flightless adults.
EGG: Gelatinous masses of 15 to 20 white eggs (becoming darker with age) are deposited on or near ground. Larvae emerge in 14 d.
LARVA: White, legless grub-like larvae feed in lower corn stems and roots. Larvae take entire season to complete development.
PUPA: Larvae leave plants to pupate in the soil. The white pupae (becoming darker with age) display the legs and wings of the developing adult.
GENERATION TIME: These beetles generally produce only a single generation per year.
DAMAGE: Four species are known from western and northern Florida. Adults feed on leaves leaving saw-toothed notches along leaf margins. Larval damage to stems leads to stunted plants and reduced yield. Boring and root feeding exposes stems to pathogens which increase the chance of lodging.
CONTROL: Crop rotation is an important control strategy for these flightless beetles which rely on walking or riding on equipment to colonize new fields. These beetles often cause more problems in fields rotated to corn from long-season, broad-leaved crops, such as peanuts, tobacco or sweetpotato. No pesticides labeled for use in Florida specifically mention these beetles on their labels.