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Three Lined Potato Beetle (Lema trilinea)

Detailing the identifying qualities of the Three Lined Potato Beetle, including physical features and territorial reach.

 Updated: 2/7/2014; Authored By Staff Writer; Content ¬©

  Three Lined Potato Beetle  
Picture of Three-Lined-Potato-Beetle

The multicolored Three-Lined Potato Beetle loves to eat a wide array of food plants making them a real pest.

This species larvae feed on the leaves of potato plants, nightshades like peppers, eggplant and tomatoes as well as tomatillos, the green 'tomatoes' used to make salsa verde. The larvae are grayish in color and are grub-like in form. Newly hatched Three-Lined Potato Beetles will congregate on a food plant and eat the leaves until only the middle vein remains. They secrete a frothy substance over themselves as they eat. Once the leaves of the plant have been completely devoured, the plant dies without bearing any edible vegetables.

They can be found in meadows, garden beds or cultivated fields. Three-Lined Potato Beetles resemble Striped Cucumber Beetles, but the potato beetle has a narrow 'waist' and the cucumber beetle does not.

Females will lay yellow eggs on leaves of the food plant. After hatching and eating the plant leaves, the larvae move to ground level and pupate in the dirt, emerging as adults. Up to two generations can be produced a year and adults can survive the winter. This makes the population growth somewhat rapid and destructive to food plants.

Three Lined Potato Beetle Information

Category: Beetle
Common Name: Three Lined Potato Beetle
Scientific Name: Lema trilinea
Other Name(s): Potato Beetle, Potato Bug

Taxonomy Hierarchy

 Arrow graphic Kingdom: Animalia
  Arrow graphic Phylum: Arthropoda
   Arrow graphic Class: Insecta
    Arrow graphic Order: Coleoptera
     Arrow graphic Family: Chrysomelidae
      Arrow graphic Genus: Lema
       Arrow graphic Species: trilinea

Size, Identifying Tags and Territorial Reach

Size (Adult, Length): Size (Adult, Length): 5 mm to 8 mm (0.195 inches to 0.312 inches)
Identifying Colors: black; yellow; red; orange
Additional Descriptors: striped, multicolored, flying, harmful

North American Territorial Reach (Though Not Limited To): Alabama; Alaska; Arizona; Arkansas; California; Colorado; Connecticut; Delaware; Florida; Georgia; Hawaii; Idaho; Illinois; Indiana; Iowa; Kansas; Kentucky; Louisiana; Maine; Maryland; Massachusetts; Michigan; Minnesota; Mississippi; Missouri; Montana; Nebraska; Nevada; New Hampshire; New Jersey; New Mexico; New York; North Carolina; North Dakota; Ohio; Oklahoma; Oregon; Pennsylvania; Rhode Island; South Carolina; South Dakota; Tennessee; Texas; Utah; Vermont; Virginia; Washington; West Virginia; Wisconsin; Wyoming; Alberta; British Columbia; Manitoba; New Brunswick; Newfoundland and Labrador; Nova Scotia; Ontario; Prince Edward Island; Quebec; Saskatchewan; Mexico

A Note About Territorial Reach: Keep in mind that an insect's reach is not limited by lines drawn on a map and therefore species may appear in areas, regions and/or states beyond those listed above. Insects are driven by environmental factors, food supplies and mating patterns and do not nescessarily work within hard-and-fast territorial lines like we humans do.

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