Anisota peigleri

Distinguished from the closely related Anisota senatoria (orangestriped oakworm) by geographic distribution—A. peigleri occurs in the southeastern U.S. while A. senatoria ranges more broadly across eastern North America. Adults are strictly diurnal, flying during daylight hours from mid-July to late August, whereas A. senatoria adults are reportedly more crepuscular or nocturnal. The species was formally described in 1975 based on these and other subtle morphological differences. Larvae cannot be reliably separated from A. senatoria without rearing to adults or molecular analysis.

Associated with oak-dominated forests and woodlands, particularly in upland and piedmont regions. Larvae feed on oak foliage in the canopy; adults are encountered in wooded areas and along forest edges where host trees occur. The species thrives in both natural forest settings and urban landscapes where oaks are planted.

Endemic to the southeastern United States: from south-eastern Kentucky, south-western Virginia, eastern Tennessee, and western North Carolina, south through western South Carolina and central Georgia into north-central Florida. The range is more restricted than that of the similar A. senatoria.

Univoltine (one generation per year). Adults emerge from overwintering pupae in mid-July and remain active through late August. Mating occurs from mid-morning to mid-afternoon. Larvae develop through late summer and early autumn, then descend to the ground to pupate and overwinter.

Larvae are specialized folivores feeding primarily on various oak species (Quercus spp.), including pin oak (Quercus palustris). They feed in tight aggregations throughout larval development. Adults do not feed; they rely on energy reserves accumulated during the larval stage.

• Quercus palustris - primary hostexplicitly documented as a larval food plant
• Quercus spp. - host genusvarious oak species utilized
• Carya spp. - occasional hosthickory reported for related species, not explicitly confirmed for A. peigleri
• Betula spp. - occasional hostbirch reported for related species, not explicitly confirmed for A. peigleri

Complete metamorphosis with four stages: egg, larva, pupa, adult. Females deposit eggs on undersides of oak leaves. Larvae hatch and feed gregariously, progressing through multiple instars. Fully grown larvae exit trees and burrow into soil to form shallow pupal chambers. Pupae overwinter, with adults emerging the following summer. No adult feeding occurs.

Larvae exhibit strong gregarious behavior, feeding in dense clusters throughout development. This clustering makes them highly visible and produces concentrated defoliation patterns. Adults are unusual among saturniids in being strictly diurnal, with mating activity concentrated in midday hours. When larval food is depleted, caterpillars may descend trees and wander in search of new host plants, making them vulnerable to ground-dwelling predators and human foot traffic on trails and sidewalks.

Larvars function as primary consumers in oak woodland food webs, converting leaf biomass into insect biomass available to predators and parasitoids. Periodic outbreaks can temporarily reduce canopy foliage, though late-season timing limits impact on tree health. The species serves as host for parasitoid wasps and flies that help regulate population dynamics. Frass production contributes to nutrient cycling beneath host trees.

Considered a minor defoliator of landscape and street oaks. Outbreaks can cause aesthetic damage and accumulate frass on sidewalks, patios, and driveways in urban settings. Rarely requires intervention; natural enemies typically collapse populations. Where management is deemed necessary, mechanical removal of larval clusters or targeted insecticide applications are effective. The species presents opportunities for public engagement with insects, as gregarious larvae and wandering caterpillars often attract attention and can serve as educational subjects.

• Anisota senatoriaExtremely similar in larval appearance and biology; historically confused with A. peigleri before 1975 description. Distinguished by broader geographic range, different adult flight period, and subtle morphological differences. Adults of A. senatoria are more nocturnal/crepuscular.
• Anisota stigmaRelated oak-feeding saturniid with similar larval morphology and gregarious feeding habits. Geographic range and adult phenology differ.
• Anisota virginiensisPink-striped oakworm with comparable biology; distinguished by larval coloration (pink stripes rather than yellow) and different geographic distribution.

• defoliator
• oak pest
• gregarious larvae
• diurnal moth
• southeastern endemic
• urban forestry
• saturniid
• univoltine

• BugGuide
• Wikipedia
• GBIF taxonomy match
• iNaturalist taxon
• NCBI Taxonomy
• Catalogue of Life
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