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Species Thera contractata - Contracted Spanworm - Hodges#7218

Contracted Spanworm - Thera contractata Early Juniper Carpet Moth  - Thera contractata Entephria ? - Thera contractata Thera? - Thera contractata Thera contractata in Northern Michigan - Thera contractata
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 Larentiinae
Tribe Hydriomenini
Genus Thera
Species contractata (Contracted Spanworm - Hodges#7218)
Hodges Number
one of 4 species in this genus in North America listed at All-Leps
local and very rare in Quebec, and apparently rare elsewhere, judging from the few images and small amount of information on the Internet
wingspan 23-25 mm, based on two Internet photos
Adult: forewing ground color white, densely speckled with brownish-gray; basal line black, wavy; AM and PM lines enclose darker median area which is wide at costa but narrow and constricted at inner margin; subterminal line white, zigzagged or toothed, with dark shading along proximal edge; terminal line black, almost straight, interrupted by white dots along its length; fringe checkered dark and light; hindwing pale brownish-gray with small discal dot, dark terminal line, and pale checkered fringe
Newfoundland to Manitoba, and adjacent northern states (but see Remarks section below)
sand dunes, rock outcrops and barrens containing foodplant
adults fly in August and September in Quebec
larvae in July and August
larvae feed on foliage of Common Juniper (Juniperus communis) and rarely, Paper Birch (Betula papyrifera) [Handfield, 1999]
There appears to be confusion or disagreement over the western distribution of this species. All-Leps shows 10 collection sites in central British Columbia, and a government of BC PDF doc indicates its presence in the province, but CBIF's Moths of Canada gives Manitoba as the western limit of T. contractata, and the only Thera species listed in British Columbia is T. otisi.
Print References
Handfield, Louis. 1999. Les Guides des Papillons du Quebec. Broquet. 662 pp.
Internet References
pinned adult image by Jim Vargo (Moth Photographers Group)
common name reference and the same live adult image by Janice Stiefel as shown at BugGuide (Moth Photographers Group)
presence in Michigan and Wisconsin plus dates and locations - search on species "contractata" (Lepidopterists Society Season Summary, U. of Florida)
distribution in Canada list of provinces (CBIF)