PestControlBasics
Menu

Identify

Treat

Local

About

Pale Beauty

Campaea perlata[5]

The pale beauty is a light-colored moth whose caterpillar, the fringed looper, is a gray to brick-red inchworm found on maples and many other trees and shrubs. A fringe of pale hairs along its lower sides and an extra pair of prolegs set it apart from other inchworms.[4][1][2]

Group
Insect
Order
Lepidoptera
Family
Geometridae
US records
32 states
Sources
5 cited
Updated
2026-11-09
Pale beauty moth resting on a leaf with its wings spread, the wings very pale whitish gray with faint lines
Pale beauty moth resting on a leaf with its wings spread, the wings very pale whitish gray with faint lines. (c) Bernie Paquette, some rights reserved (CC BY) — via iNaturalist, CC BY 4.0
On this page
  1. Identification
  2. Look-alikes
  3. Where it lives
  4. Biology
  5. Damage and signs
  6. Health risk
  7. Control
  8. Related profiles
  9. Common questions
  10. Sources

How to identify it

  • Two features set the caterpillar apart from other inchworms: an extra, reduced pair of prolegs on the fifth abdominal segment, and a fringe of short, thick, pale hairs along the lower sides of the abdomen.[1][2]
  • Its color ranges from gray to brick red or reddish brown, less often smoky green. A dark band runs at a slant across the head from the top down to the eye, and the tan breathing pores are ringed with black.[1][2]
  • The underside is noticeably flattened and pale, green down the middle and frosty toward the fringe. Full-grown caterpillars reach about 4 cm (1 1/2 inches).[1]
  • The adult is a light-colored moth.[4]

Look-alikes

Look-alikeHow to tell them apart
Other inchworms (loopers)Almost all loopers have just one pair of prolegs in the middle of the body, on the sixth abdominal segment. The fringed looper has an extra, reduced pair on the fifth segment, plus the fringe of pale hairs along its lower sides, which resembles the thick-based hairs of underwing moth caterpillars and other caterpillars that rest on bark.[2][1]

Where it lives

The USDA Forest Service describes it as transcontinental in Canada, reaching south in the East to Georgia (in the mountains) and Arkansas, in forests, woodlands and parks.[1]

US map: public records from 32 states since 1990 (GBIF).

Biology and life cycle

The caterpillars eat many woody shrubs and trees, including alder, aspen, birch, cherry, hazelnut, maple, oak, rose, serviceberry and willow, and conifers such as fir, hemlock and larch. The USDA Forest Service singles out maples.[1][2]

There are two generations a year in the North. In Connecticut, caterpillars that spent the winter mature from May into June, and the summer generation matures in July and August; in Maryland the first generation can mature as early as April and the second runs from late June into September.[1][2]

The caterpillars make hyperactive antifreeze proteins. In laboratory measurements they showed a freezing point depression of 6.4 °C (about 11.5 °F), and researchers purified two new antifreeze proteins with no match among known protein sequences.[3]

In a 1968 experiment, pale beauty moths offered black and white backgrounds rested on the background that suited their light color, and painting the scales around their eyes didn't change the choice, which suggests the preference is inborn.[4]

Damage and signs

  • The caterpillars eat the leaves of many trees and shrubs and are very common in Connecticut, but neither USDA Forest Service guide describes noticeable damage.[1][2]

Health risk

Neither USDA Forest Service guide mentions any bite, sting or other risk to people.[1][2]

Control

Prevention

Neither USDA Forest Service guide recommends any control for the fringed looper.[1][2]

Common questions

What is the gray inchworm with a fringe along its sides?
Probably a fringed looper, the caterpillar of the pale beauty. Check for a fringe of pale hairs along the lower sides and an extra pair of small prolegs in front of the usual ones.[1][2]
How do fringed loopers survive the winter?
The caterpillars spend the winter and, in Connecticut, finish maturing in May and June. They make hyperactive antifreeze proteins that strongly lower the temperature at which they freeze.[1][3]
Which trees do fringed loopers feed on?
Many: maples especially, plus alder, aspen, birch, cherry, hazelnut, oak, rose, serviceberry, willow, fir, hemlock and larch.[1][2]

Sources

  1. USDA Forest Service, Forest Health Technology Enterprise Team, “Geometroid Caterpillars of Northeastern and Appalachian Forests, FHTET-2001-10 (D. L. Wagner, D. C. Ferguson, T. L. McCabe and R. C. Reardon, September 2001; scanned copy).” archive.org/details/geometroidcaterp00wagn (accessed 2026-11-09)
  2. USDA Forest Service, Forest Health Technology Enterprise Team, “Caterpillars of Eastern Forests, FHTET-96-34 (D. L. Wagner, V. Giles, R. C. Reardon and M. L. McManus, November 1997; scanned copy).” archive.org/details/caterpillarsofea001997 (accessed 2026-11-09)
  3. Biochemistry (via NCBI PubMed), “The Thr- and Ala-rich hyperactive antifreeze protein from inchworm folds as a flat silk-like beta-helix (F.-H. Lin, P. L. Davies and L. A. Graham; Biochemistry 50(21): 4467-4478, 2011; abstract).” pubmed.ncbi.nlm.nih.gov/21486083/ (accessed 2026-11-09)
  4. Science (via NCBI PubMed), “Cryptic moths: effects on background selections of painting the circumocular scales (T. D. Sargent; Science 159(3810): 100-101, 1968; abstract).” pubmed.ncbi.nlm.nih.gov/17737484/ (accessed 2026-11-09)
  5. iNaturalist, “Campaea perlata taxon page (order and family).” www.inaturalist.org/taxa/81681 (accessed 2026-11-09)

Updated 2026-11-09. Built from sourced records. Spot an error? Tell us.