Macrosteles quadrilineatus

(Forbes, 1885)

Aster leafhopper, Six-spotted leafhopper

is a small leafhopper native to the United States and a major agricultural pest. It is the primary of phytoplasma, transmitting the to vegetable crops including carrot, celery, lettuce, and potato. migrate northward in spring on southerly winds, often arriving in the Midwest and northern regions earlier and in greater numbers than resident . The species exhibits feeding on numerous grasses, cereals, and broadleaf plants.

Aster leafhopper by Whitney Cranshaw. Used under a CC BY 3.0 license.

Macrosteles P1280445a by
xpda. Used under a CC BY-SA 4.0 license.

Macrosteles P1300228a by
xpda. Used under a CC BY-SA 4.0 license.

Pronunciation

How to pronounce Macrosteles quadrilineatus: /ˌmæ.krəˈstiː.liːz ˌkwɒ.drɪ.lɪˈneɪ.ə.təs/

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

Identification

Males measure approximately 3.3 mm in length, females about 3.7 mm. Forewings are greyish-green; is yellowish-green. Six pairs of minute black spots or streaks on the provide the alternative 'six-spotted leafhopper.'

Images

Habitat

Found in agricultural fields, particularly carrot, celery, lettuce, and potato crops. Overwinters primarily on grasses and cereals. In field experiments, abundance is influenced by surrounding vegetation: grassy weeds and cereals increase , while broadleaf weeds reduce them.

Distribution

United States; Canada (Alberta). occurs from southern areas northward to the Midwest and northern United States and the Western Canadian Prairies.

Seasonality

migrate northward in spring on strong southerly winds. In the upper Midwest and northern United States, migrants arrive earlier and typically exceed resident in number. Activity declines after freezing temperatures in fall.

Diet

Phloem feeder; feeds intracellularly by penetrating layers with stylets to reach phloem tissue. feed on carrot, dill, potato, and radish, though these support poor reproductive performance.

Host Associations

Aster yellows phytoplasma (Candidatus Phytoplasma asteris, 16SrI) - Primary transmission agent; phytoplasma causes in numerous crops and weeds
carrot (Daucus carota) - Preferred feeding and reproductive ; major crop pest
celery (Apium graveolens) - Affected by transmission
lettuce (Lactuca sativa) - Affected by transmission
potato (Solanum tuberosum) - feeding ; poor for breeding
barley (Hordeum vulgare) - Experimental for probing studies
canola/rapeseed (Brassica napus) - Marginal ; does not support complete development
oats (Avena sativa) - and rearing
rye (Secale cereale) - plant
corn (Zea mays) - -laying
dill (Anethum graveolens) - feeding
radish (Raphanus sativus) - feeding ; poor for breeding
clovers (Trifolium spp.) - -laying
spelt (Triticum spelta) - Border crop; associated with reduced leafhopper abundance in adjacent carrot plots compared to other cereals
grasses (Poaceae) - Preferred for oviposition and ; attract leafhoppers in choice tests
broadleaf weeds - Repel leafhoppers in choice tests; carrot plots with broadleaf weeds show 59% fewer leafhoppers than those with crabgrass or carrot alone

Life Cycle

are laid on a wide range of plants including grasses, clovers, corn, oats, rye, carrots, and various weeds. Eggs hatch in approximately one week. Complete takes about four weeks under favorable conditions.

Behavior

Exhibits migratory : are carried northward in spring on strong southerly winds. Probing behavior involves intracellular stylet penetration to reach phloem, creating nine distinct waveform patterns detectable by electropenetrography. Males show higher frequency of nonprobing activities and phase events than females. Feeding behavior facilitates growth of Salmonella enterica on leaves by creating localized beneficial through cellular damage. Distribution of probing attempts is altered by presence of S. enterica. Infected leafhoppers show temporary preference for phytoplasma-infected plants at 2 weeks post-, but this preference disappears by 4 weeks.

Ecological Role

Primary of phytoplasma, a significant plant affecting vegetable crops, weeds, and ornamentals. Modifies phyllosphere microbial ; facilitates persistence and growth of Salmonella enterica on leaf surfaces through feeding-induced cellular damage and solute leakage. Serves as prey for including Pachygonatopus minimus, Neogonatopus ombrodes, and Epigonatopus plesius.

Human Relevance

Major agricultural pest due to transmission of , causing yellowing, stunting, and deformed flowers in vegetable crops. Management strategies include adjusting weed management (favoring broadleaf weeds over grasses), selecting border crops carefully (spelt reduces abundance compared to wheat, barley, or triticale), and timing control measures to account for spring . No specific recommendations developed for wheat .

Similar Taxa

Macrosteles fascifronsCongeneric ; both are small leafhoppers in the same with similar and agricultural pest status
other Macrosteles species members share small size, similar body proportions, and phloem-feeding habits; identification requires examination of spot patterns and genitalia