Largus Bug

Largus succinctus (L.), like other true bugs, has sucking mouth parts. Being general feeders, they suck juices from a variety of plants such as oak, wax-myrtle and other woodland foliage and sometimes from weeds. Generally, they cause little damage to the plants upon which they feed. However, in the fall they leave their host plants and seek cracks and crevices in which to spend the winter. They also mate and disperse. Large numbers of these bugs in the landscape can cause some concern.
Description: Both families (Largidae and Pyrrhocoridae) of these bugs are similar in appearance and habits. The largus bug, Largus succinctus (Linnaeus) (Largidae), is about 1/2-inch long, elongated oval and flattened, steel blue in color, and have reddish-yellowish markings around margins of the shield behind the head (pronotum) and abdomen. The outer margins of the pronotum are rounded.
Habitat, Food Source(s), Damage: Nymphs and adults have sucking mouthparts. Although largus bugs are general feeders, sucking juices from a variety of plants such as oak, wax myrtle and other woodland foliage or, occasionally, weeds, they generally cause little injury to plants upon which they feed.
Largus bugs generally cause little injury to plants upon which they feed. However, in the fall nymphs and adults leave their host plants and seek cracks and crevices in which to spend the winter. They can be common around the home during the fall, crawling randomly around the ground. Cotton stainer nymphs (second and third instars) feed together (gregariously) on cotton bolls while that last stage and adults wander freely over the plant. On long-staple cotton varieties, cotton stainers injure developing bolls by puncturing the seeds and causing plant sap to exude from the feeding sites, resulting in yellow-stained lint and poorly developed bolls.
Pest Status: Largus bugs are seed feeders, occasionally a nuisance when in high numbers around the home; cotton stainers, or "red bugs", occasionally damage long-staple cotton; both are medically harmless.
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