Other Common Names
Peppered Moth (in Eurasia)
Cleft-headed Looper (larva)
Synonyms and other taxonomic changes
North American individuals are subspecies B. b. cognataria; Eurasian individuals are subspecies B. b. betularia
Explanation of Names
BETULARIA: from the birch genus Betula, one of the larval host plants
Identification
Adult: color of forewing and hindwing varies from pale gray to dark blackish brown with wavy black lines and heavy speckling of dark gray spots
Larva: a long slender twig mimic - usually greenish (immature) or grayish (mature) body with depression between pointed lobes of head, and tiny speckles on dorsal surface of body; head reddish-brown; thoracic legs yellowish-brown; tubercles present on prothorax and abdomen
Range
holarctic: coast-to-coast in North America and temperate Eurasia
Season
adults fly from April to September
larvae present from July to November
Food
larvae feed on wide variety of trees and shrubs (alder, birch, blueberry, cherry, currant, dogwood, elm, ginkgo, hackberry, larch, maple, poplar, redroot, soapberry, strawberry, sweet fern, tamarack, walnut, white pine, willow)
Life Cycle
usually one generation per year (partial second generation in some areas); overwinters as pupa in soil or under leaf litter
Remarks
This species is often cited as an example of industrial melanism in England (see Internet References for articles and sample photos)
Internet References
live adult images of light and dark forms, plus discussion on industrial melanism (John Kimball, Massachusetts)
live adult images on tree trunks, showing cryptic coloration of light and dark forms (U. of Texas)
live adult images (Lynn Scott, Ontario)
adult images and other info (Larry Line, Maryland)
pinned adult images of light and dark forms (CBIF)
pinned adult image plus description and other info (Jeff Miller, US Geological Survey)
pinned adult image (Insects of Quebec)
live larva image plus description, biology, common name reference for larva [Cleft-headed Looper] and other info (forestpests.org)
live larva image - immature stage (Tony Thomas, New Brunswick)
live larva image - mature stage (Tony Thomas, New Brunswick)
common name reference for adult [Pepper & Salt Geometer] plus other info (Ohio State U.)
debate & discussion on industrial melanism etc. in reference to this species (wiki.cotch.net)
