Fauna
Insect · GBIF taxon 9002107

Karner Blue

Plebejus samuelis

Also known as Karner Blue Butterfly

Karner blue butterflies rely entirely on wild lupine plants to complete their lifecycle in sun-drenched pine barrens and oak savannas across the northern United States. Females lay eggs exclusively on lupine foliage, where caterpillars feed while secreting sugary honeydew to attract tending ants that offer protection from predators. Producing two flights each summer, adults flutter low to the ground to sip nectar from a variety of native wildflowers.

PollinatorSymbiont
Karner Blue reference1 / 7
Licensed reference(c) Aaron Carlson, some rights reserved (CC BY) · cc-by
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EndangeredConservation statusIUCN Red List categoriesLCNTVUENCREWEXEndangeredRed List categories, explained →
Key facts
Diet & prey
  • Wild lupine foliage
  • Wildflower nectar
Predators
  • Spiders
  • Robber flies
  • Dragonflies
ThreatsHabitat loss, fire suppression, development, loss of wild lupine
HabitatsPine barrens, oak savannas, sand prairies
Life span3–5 days (adult)
Classification
  1. FamilyLycaenidae
  2. SpeciesPlebejus samuelis
Range & activity
Range data is not available yet.
Safe observation
Interaction riskLow
  1. Low
  2. Moderate
  3. High
  4. Very high
Why interaction risk is low
Safe to observe at a normal distance.
What to notice
Look for a tiny butterfly with vibrant silvery-blue upper wings on males and orange crescents lining the underwing margins.
Support conservation
Observe from designated boardwalks, never collect specimens, and avoid disturbing sandy lupine patches.
Responsible observation
  • Spotting Season: Watch for adult flights in late spring and mid-summer around blooming lupine.
  • Trail Etiquette: Stick strictly to established paths in pine barrens to prevent trampling fragile eggs.
Related species
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