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Species Lycia ursaria - Stout Spanworm Moth - Hodges#6651

Inchworm like caterpillar - Lycia ursaria Is this Lycia? - Lycia ursaria 6651 Stout Spanworm Moth - Lycia ursaria - male Lycia ursaria - male Unknown & Beautiful Caterpillar, head - Lycia ursaria Prominent Moth? - Lycia ursaria - male moth - Lycia ursaria - male Lycia ursaria female - Lycia ursaria - female
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 Lycia
Species ursaria (Stout Spanworm Moth - Hodges#6651)
Hodges Number
Synonyms and other taxonomic changes
Lycia ursaria (Walker, 1860)
Biston ursaria Walker, 1860
locally common
wingspan to 45 mm
Full grown larvae are 50mm(1)
Adult: thorax and abdomen bulky, very hairy; male forewing broad, evenly gray, heavily speckled with black; three black wavy lines (sometimes broken) cross the wing; subterminal line white; hindwing similar but color more muted; female has reduced wings and does not fly
southern Canada and northern United States, south to New Jersey and Iowa
mixed and deciduous woods; males are nocturnal and come to light
adult males fly from March to June
Larvae are present from May to July(1)
Larvae feed on the leaves of alder, apple, ash, basswood, birch, blueberry, dogwood, elm, hawthorn, poplar, willow and other broadleaved trees and shrubs
Life Cycle
One generation per year
Overwinters as pupae in the ground(1)
A bulky and very hairy moth, easily mistaken for a noctuid, notodontid, or other non-geometrid moth
See Also
Twilight Moth (Lycia rachelae) male lacks speckling on wings, and has yellowish strip along costa of forewing (compare images of both species at CBIF)
Woolly Gray (Lycia ypsilon) male has grayish-brown forewing with lighter median area, and a more southern distribution (doesn't occur in Canada)
Print References
Rindge, Frederick H. 1975. A revision of the New World Bistonini, (Lepidoptera, Geometridae). Bulletin of the AMNH ; v. 156, article 2.(2)
Internet References
pinned adult image of male (CBIF)
live adult image of male (Lynn Scott, Ontario)
distribution in Canada list of provinces (CBIF)
Works Cited
1.Eastern Forest Insects
Whiteford L. Baker. 1972. U.S. Department of Agriculture · Forest Service.
2.A revision of the New World Bistonini, (Lepidoptera, Geometridae).
Frederick H. Rindge. 1975. American Museum of Natural History 156(2):.