Lygus lineolaris

(Palisot de Beauvois, 1818)

tarnished plant bug, North American tarnished plant bug

Lygus lineolaris, commonly known as the , is a highly mirid bug and major agricultural pest throughout North America. It attacks over half of all cultivated plant grown in the United States, with particularly significant damage to cotton, alfalfa, strawberries, and conifer seedlings. The species has and causes injury by feeding on developing reproductive structures, resulting in deformed fruits, shed squares, and reduced yields. It serves as prey for numerous natural enemies including spiders, predatory , and solitary .

Lygus lineolaris by (c) Katja Schulz, some rights reserved (CC BY), uploaded by Katja Schulz. Used under a CC-BY license.Lygus lineolaris by (c) Katja Schulz, some rights reserved (CC BY). Used under a CC-BY license.Lygus lineolaris by (c) Bill Keim, some rights reserved (CC BY). Used under a CC-BY license.

Pronunciation

How to pronounce Lygus lineolaris: /ˈlaɪɡəs lɪniˈoʊlərɪs/

These audio files are automatically generated. While they are not always 100% accurate, they are a good starting point.

Identification

can be distinguished from similar Lygus by the combination of the dark triangular scutellum, variable green-to-brown coloration with reddish markings, and overall size. Nymphs are differentiated from aphids, cotton fleahoppers, and leafhopper nymphs by their broader body shape, larger size, rapid movement, red-tipped , and the distinctive black spot pattern on late instars (four thoracic spots plus one abdominal spot). The species is most reliably separated from the western tarnished plant bug (Lygus hesperus) and pale legume bug (Lygus elisus) by geographic distribution and subtle morphological differences requiring expert examination.

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Appearance

are approximately 6 mm (¼ inch) in length with an oval, somewhat flattened body. Coloration varies from pale green to yellowish-brown with reddish-brown to black markings. A conspicuous dark triangular scutellum is present in the center of the back. Nymphs are uniformly pale green with red-tipped ; late instars display four prominent black spots on the and one large black spot near the base of the . Nymphs lack fully developed wings but can move rapidly through foliage.

Habitat

Found in diverse agricultural and natural including cultivated fields, pastures, rangeland, field margins, and areas. Strongly associated with succulent, flowering vegetation. Common in alfalfa fields, clover stands, and weedy areas with such as dock, mustard, pigweed, Russian thistle, vetches, and wild sunflower. In cotton systems, build in field edges adjacent to alternative host plants before moving into crop interiors.

Distribution

Native to and widespread throughout North America. Occurs across the United States from coast to coast, throughout southern Canada (Alberta, British Columbia, Manitoba, New Brunswick, Newfoundland, Nova Scotia, Ontario, Prince Edward Island, Quebec, Saskatchewan), and extends south through Mexico into Central America (Guatemala, Honduras, El Salvador) and the Caribbean (Bermuda). Particularly abundant in the Mid-South and Mississippi Delta regions.

Seasonality

vary regionally. In Arkansas soybean systems, peak occur mid-June to late July, with brief residence on soybean before to preferred . In Texas cotton, present throughout the fruiting period requiring scouting at 4- to 5-day intervals. adults emerge in spring and populations build through summer. Nymphs present during growing season; very few nymphs found relative to adult numbers in some soybean studies, suggesting ongoing immigration rather than in-field .

Diet

Highly ; feeds on over half of all cultivated plant in the United States. used to extract plant fluids. On cotton: feeds on terminals, squares, flowers, and small bolls. On strawberries: developing achenes during early fruit stages, shifting to receptacle tissue near achenes in later stages. Strong preference for legumes including alfalfa, clover, and vetches over cotton. Metataxonomic analysis confirms diet including both plant and material in strawberry systems.

Host Associations

  • Gossypium hirsutum - feeds_oncotton; major economic , attacks squares, flowers, bolls
  • Medicago sativa - feeds_onalfalfa; preferred ,
  • Fragaria × ananassa - feeds_oncultivated strawberry; causes 'buttoning' malformation
  • Trifolium spp. - feeds_onclovers; common wild
  • Vicia spp. - feeds_onvetches; preferred legume
  • Rumex spp. - feeds_ondock; wild
  • Amaranthus spp. - feeds_onpigweed; wild
  • Salsola tragus - feeds_onRussian thistle; wild
  • Helianthus annuus - feeds_onwild sunflower; wild
  • Sinapis arvensis - feeds_onmustard; wild

Life Cycle

with , nymph, and stages. Eggs deposited in plant tissue. Nymphs pass through five instars; late instars distinguished by black thoracic and abdominal spotting. Developmental rates and seasonal patterns vary by region and plant. In the Mississippi Delta, studies of hibernation and host plant sequences indicate complex seasonal movement patterns between sites, spring hosts, and summer crop hosts. Adults are the primary overwintering stage.

Behavior

Highly mobile; capable of and long-distance between plants. Nymphs move rapidly through foliage despite lacking functional wings. Attracted to succulent growth and flowering plants. Exhibits enantiospecific attraction to (S)-(+)-linalool, a ubiquitous floral volatile, with field capture rates significantly higher for this stereoisomer than (R)-(-)-linalool. Visual cues influence trapping ; red traps enhance capture rates when combined with linalool lures, white traps do not. Females attracted to floral nectar sources including wild carrot (Daucus carota), goldenrod (Solidago), and milkweed (Asclepias).

Ecological Role

Major herbivorous pest in agricultural with significant economic impact. Serves as important prey item supporting diverse natural enemy . Documented prey for at least 25 including spiders (Oxyopes salticus, Misumenops spp., Pisaurina mira, Thiodina puerpera), predatory (Orius insidiosus, Jalyssus wickami, Stiretrus anchorago, Phymata pennsylvanica), and solitary (Anacrabro ocellatus, which specializes almost exclusively on L. lineolaris). suppression by natural enemies, particularly crab spiders on flowering Aster pilosus, has been demonstrated to reduce local TPB densities. feeding habits may include on other arthropods, though primarily phytophagous.

Human Relevance

Significant agricultural pest causing economic damage to cotton, strawberries, alfalfa, vegetables, stone fruits, conifer seedlings, and numerous other crops. Feeding injury manifests as deformed bolls, dirty bloom, square and boll shedding, stunted growth, and reduced lint quality in cotton; seediness or buttoning in strawberries; and general fruit malformation across multiple . Management relies on integrated pest monitoring using sweep nets (pre-peak bloom) and drop cloths (post-peak bloom), with treatment thresholds based on fruiting stage and pest . resistance documented in some ; selective insecticides including acetamiprid and sulfoxaflor show efficacy with reduced non-target impacts compared to broad-spectrum alternatives. Attraction to (S)-(+)-linalool provides basis for improved monitoring traps.

Similar Taxa

  • Lygus hesperusWestern tarnished plant bug; similar appearance, , and damage, but predominates in western North America whereas L. lineolaris dominates eastern regions. Requires expert morphological examination for reliable separation.
  • Lygus elisusPale legume bug; similar appearance and , occurs in same cropping systems. Distinguished by subtle coloration differences and geographic patterns.
  • Adelphocoris rapidusRapid plant bug; similar size and general appearance, also pest of cotton. Distinguished by different body proportions and lack of distinct triangular scutellum marking.
  • Pseudatomoscelis seriatusCotton fleahopper; similar nymphal stages may be confused in field. Distinguished by smaller size, different antennal coloration, and more slender body form.

More Details

Monitoring and Trapping

Recent research demonstrates that L. lineolaris exhibits stereospecific olfactory attraction to (S)-(+)-linalool, significantly increasing female capture rates in field traps compared to the (R)-enantiomer or racemic mixtures. This finding, combined with visual preference for red trap surfaces, provides improved monitoring tools for agricultural systems.

Natural Enemy Specialization

The solitary Anacrabro ocellatus (Crabronidae) is a notable that hunts almost exclusively for L. lineolaris, provisioning subterranean nest with 4-9 individuals as food for single larvae. This represents a significant case of prey-specific /predator specialization on an economically important pest.

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Sources and further reading