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Species Biston betularia - Pepper & Salt Geometer - Hodges#6640

 Peppered Moth - Biston betularia - male Pepper & Salt Geometer - Biston betularia Green Caterpillare - Biston betularia Biston betularia? - Biston betularia Pepper & Salt Geometer - Hodges#6640 - Biston betularia - male Geometrid - Biston betularia Pepper & Salt Geometer - Hodges#6640 - Biston betularia Inchworm pretending to be a dogwood twig - Biston betularia
Show images of: caterpillars · adults · both
Kingdom Animalia (Animals)
Phylum Arthropoda (Arthropods)
Subphylum Hexapoda (Hexapods)
Class Insecta (Insects)
Order Lepidoptera (Butterflies and Moths)
Superfamily Geometroidea (Geometrid and Swallowtail Moths)
Family Geometridae (Geometrid Moths)
Subfamily Ennominae
Tribe Bistonini
Genus Biston
Species betularia (Pepper & Salt Geometer - Hodges#6640)
Hodges Number
Other Common Names
Peppered Moth (in Eurasia)
Cleft-headed Looper (larva)
Synonyms and other taxonomic changes
Biston betularia (Linnaeus, 1758)
Phalaena betularia Linnaeus, 1758
Amphidasys betularia
* phylogenetic sequence #196200
Explanation of Names
Specific epithet betularia from the birch genus, Betula, one of the larval host plants. (1)
Wingspan up to 48 mm.
Larvae up to 70 mm.
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.
Examples of melanic forms:

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.
Holarctic: coast-to-coast in North America and temperate Eurasia.
CA to WA and higher elevations in the Rocky Mtn states, s. Appalachians to ME & MN, BC to NL. (2)
Forests, woodlots, parks.
Adults mostly fly April to September. (2) Larvae present July to November.
Larvae feed on a 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.
Often cited as an example of industrial melanism in England (see Internet References for articles and sample photos).

In North America, there are 2 sub-species:
Biston betularia cognataria
Biston betularia contrasta
Print References
Rindge, F.H. 1975. A revision of the New World Bistonini, (Lepidoptera, Geometridae). Bulletin of the AMNH 156, article 2. (3)
Internet References
live adult images of light and dark forms, plus discussion on industrial melanism (John Kimball, Massachusetts)
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 (Insects of Quebec)
live larva image plus description, biology, common name reference for larva [Cleft-headed Looper] and other info (
live larva image - immature stage (Tony Thomas, New Brunswick)
live larva image - mature stage (Tony Thomas, New Brunswick)
Works Cited
1.An accentuated list of the British Lepidoptera, with hints on the derivation of the names.
Anonymous. 1858. The Entomological Societies of Oxford and Cambridge.
2.North American Moth Photographers Group
3.A revision of the New World Bistonini, (Lepidoptera, Geometridae).
Frederick H. Rindge. 1975. American Museum of Natural History 156(2):.