Agriotes lineatus

Distinguished from similar Agriotes species by the pronotum shape (as long as or slightly longer than wide) and more prominent longitudinal elytral stripes. Agriotes proximus is nearly identical morphologically and molecularly (>99% COI gene similarity), differing subtly in pronotum proportions and male genitalia (shorter aedeagus, less sharp paramere hooks in A. lineatus). Larvae are indistinguishable from A. proximus; from A. obscurus larvae, they differ in having shorter, parallel-sided, subquadrate abdominal spiracles and specific mandibular and frontoclypeal angles. Molecular identification is feasible but challenging due to extreme similarity with A. proximus.

Native habitat includes non-farmed areas and grasslands; adults feed on grass leaves. In agricultural settings, invades fields from adjacent grasslands. Larvae inhabit soil, preferring acidic, humus-rich soils with higher moisture. In central Europe, found at higher altitudes (400–500 m) with lower temperatures and higher winter precipitation.

Native to most of Europe (absent from northern Norway, Sweden, Finland, and Russia), western Asia (Armenia, Azerbaijan, Georgia, Iran, Kazakhstan, Kyrgyzstan, Lebanon, Syria, Turkmenistan, Turkey), and the Near East. Introduced and invasive in western Canada (British Columbia, Vancouver Island), Washington State (USA), and Atlantic Canada (Nova Scotia). Unconfirmed records exist for Massachusetts, eastern Russia, and Australia.

Adults emerge in spring, with peak activity in late May and early June. Egg laying begins in April, peaking in May and June in central Germany. Adults are active during afternoon and evening hours. Adults have a longer lifespan than some congeners and overwinter.

Adults feed on leaves of grasses. Larvae are polyphagous, feeding on roots, seeds, and tubers of various plants including cereal crops (maize, wheat), potatoes, strawberries, and sugar beet.

• Solanum tuberosum - larval food plantpotato tubers attacked, major crop pest
• Zea mays - larval food plantroots and seeds attacked
• Triticum - larval food plantroots and seeds of wheat attacked
• Fragaria - larval food plantroots attacked
• Beta vulgaris - larval food plantsugar beet tubers attacked
• Poaceae - adult food plantadults feed on grass leaves in native grassland habitat

Life cycle spans approximately 3 years in central Germany, likely longer further north. Eggs are laid in soil close to the surface in spring. Larvae emerge after approximately 3 weeks and pass through up to 12 instars over 2–3 years. Pupation occurs in soil and lasts 3–4 weeks. Adults emerge in spring and can overwinter.

Adults exhibit clicking mechanism for righting themselves when overturned. Males are attracted to female sex pheromones (primarily geranyl octanoate with geranyl butanoate). In trap studies, A. lineatus males show higher activity and longer movement distances than A. obscurus; they frequently enter traps baited for other Agriotes species unless both trap types are present. Adults prefer humid sites during dry weather and avoid hedgerows. Larvae are attracted to autoclaved millet substrate used in biocontrol formulations.

In native grasslands, adults function as herbivores on grasses and larvae as root-feeding detritivores/herbivores. In agricultural ecosystems, larvae become significant pests through root and tuber feeding. Serves as host for entomopathogenic fungi including Metarhizium brunneum. Pheromone-based monitoring indicates population stability in heterogeneous landscapes.

Major agricultural pest in Europe and invasive regions, particularly damaging to potato, maize, and cereal production. Larval damage can affect more than 90% of potato tubers in heavily infested fields. Subject to integrated pest management including pheromone monitoring (10:1 geranyl octanoate:geranyl butanoate in Vernon Pitfall Traps), crop rotation, timed tillage and irrigation to desiccate eggs and larvae, and biological control attempts with entomopathogenic fungi and nematodes. Mass trapping and mating disruption using pheromones have been attempted with limited success. Detected via environmental DNA in green yard waste, indicating potential for spread through waste movement.

• Agriotes proximusExtremely similar morphology, identical pheromones, indistinguishable larvae, >99% COI gene similarity; differs in pronotum slightly wider than long and male genitalia with thinner, sharper paramere hooks
• Agriotes obscurusSimilar wireworm pest; larvae differ in abdominal spiracle shape (longer in A. obscurus), mandibular tooth angle, and frontoclypeal angle
• Agriotes sputatorSimilar striped elytra but stripes less prominent than in A. lineatus
• Agriotes modestusSimilar striped elytra but stripes less prominent than in A. lineatus

• agricultural pest
• wireworm
• invasive species
• pheromone
• integrated pest management
• soil-dwelling

• BugGuide
• Wikipedia
• GBIF taxonomy match
• iNaturalist taxon
• NCBI Taxonomy
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• Mass trapping wild Agriotes obscurus and Agriotes lineatus males with pheromone traps in a permanent grassland population reservoir
• Behavioural responses of Agriotes lineatus and Agriotes litigiosus wireworms to natural substances, synthetic volatile organic compounds and entomopathogenic fungi: Implications for sustainable pest management
• Interaction of the wireworm species Agriotes obscurus , A. sputator and A. lineatus with a new granule formulation of Metarhizium brunneum
• Mark–recapture of Agriotes obscurus and Agriotes lineatus with dense arrays of pheromone traps in an undisturbed grassland population reservoir
• Influence of climatic conditions on the distribution, abundance and activity of Agriotes lineatus L. adults in sex pheromone traps in Croatia
• Distribution of two European elaterids, Agriotes obscurus and A. lineatus in British Columbia: New records, and potential implications of their dispersal
• THE BEHAVIOUR OF ADULT CLICK BEETLES OF THE GENUS AGRIOTES (A. OBSCURUS L., A. LINEATUS L., AND A. SPUTATOR L.)
• Behavioral response of three subterranean pests (Agriotes lineatus, Diabrotica virgifera virgifera, Phyllopertha horticola) to the fungal volatile organic compounds 1-octen-3-ol and 3-octanone