Fauna
Insect

Forest Tent Caterpillar Moth

Malacosoma disstria

Also known as Forest Tent Caterpillar

Forest tent caterpillar moths produce distinctive larvae marked with broad blue stripes and keyhole-shaped white spots along their backs. Unlike their tent-building relatives, these caterpillars weave flat silk mats on tree trunks for group molting rather than constructing enclosed shelters. Periodically, populations explode into massive outbreaks that temporarily defoliate vast stretches of deciduous forest before adult moths emerge in midsummer.

DefoliatorSocial CaterpillarMoth
Forest Tent Caterpillar Moth reference1 / 7
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Least ConcernConservation statusIUCN Red List categoriesLCNTVUENCREWEXLeast ConcernRed List categories, explained →
Key facts
Diet & preySugar Maple Leaves, Quaking Aspen Leaves, Oak Leaves
Predators
  • Birds
  • Parasitoid Flies
  • Predatory Ground Beetles
ThreatsParasitoid flies, viral infections, late spring freezes, and synthetic insecticides
HabitatsDeciduous forests, mixed woodlands, suburban yards, and orchards
Life span1 year total (adult stage lasts 2–5 days)
Classification
  1. OrderLepidoptera
  2. FamilyLasiocampidae
  3. GenusMalacosoma
  4. SpeciesMalacosoma disstria
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
Larval setae can cause mild skin irritation; avoid direct handling or wear protective gloves.
Why it is dangerous
Setae covering the caterpillars contain mild irritants that can trigger contact dermatitis in sensitive skin.
How to recognize a risky encounter
Look for hairy blue and black caterpillars with a row of keyhole-shaped white spots along the spine.
What to do
Observe larvae on branches without touching them, or wear thick gloves if removing them from foliage.
Responsible observation
  • Spotting Larvae: Look for blue-banded caterpillars featuring keyhole-shaped white markings on their backs.
  • Finding Adults: Search near outdoor lights in midsummer when short-lived, tan-colored moths emerge.
  • Molt Mats: Check tree trunks for silky woven sheets where caterpillars gather during skin-shedding phases.
Related species
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Found in Collections

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Moonlight Marvels

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