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Photos of insects and people from the 2022 BugGuide gathering in New Mexico, July 20-24

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Photos of insects and people from the Spring 2021 gathering in Louisiana, April 28-May 2

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Species Euthyatira semicircularis - Hodges#6241

Euthyatira semicircularis Euthyatira semicircularis Euthyatira semicircularis and another one this seems like it could be the female? - Euthyatira semicircularis Moth - Euthyatira semicircularis Semicircular Thyatirid - Euthyatira semicircularis moth - Euthyatira semicircularis Drepanidae: Euthyatira semicircularis - Euthyatira semicircularis
Show images of: caterpillars · adults · both
Kingdom Animalia (Animals)
Phylum Arthropoda (Arthropods)
Subphylum Hexapoda (Hexapods)
Class Insecta (Insects)
Order Lepidoptera (Butterflies and Moths)
Superfamily Drepanoidea (Hooktip and False Owlet Moths)
Family Drepanidae (Hooktip and False Owlet Moths)
Subfamily Thyatirinae (False Owlet Moths)
Tribe Macrothyatirini
Genus Euthyatira
Species semicircularis (Euthyatira semicircularis - Hodges#6241)
Hodges Number
Synonyms and other taxonomic changes
described in 1881 by Grote, who originally placed it in genus Bombycia
one of 3 species in this genus in North America listed at All-Leps
wingspan about 39-45 mm, based on three Internet photos
Adult: forewing silvery gray in male, dark gray in female; 3 or 4 arc-shaped black lines cross wing in basal area, but are often faint or indistinct; semicircular whitish or pale yellow patch at base, bordered by black; pale gray apical patch bordered by black oblique apical dash; PM line dark, double, irregular, scalloped; subterminal line faint, scalloped, terminates at apical dash; hindwing light yellowish-gray with dark veins prominent in center of wing
California to British Columbia, east to Utah
wet western coniferous forests
adults fly mainly from May to July in California
Internet References
pinned adult image taken from this page (CBIF)
pinned adult image and photos of related species by Jim Vargo (Moth Photographers Group)
species account [containing the wrong photo -- of Ceranemota tearlei -- as of February 2008, instead of the correct photo] plus description, habitat, flight season (Jeff Miller, Macromoths of Northwest Forests and Woodlands, USGS)
pinned adult images of male and female by Paul Opler, plus US distribution map (
presence in California; list of 15 specimen records with dates and locations (U. of California at Berkeley)
presence in Utah; list (Joel Johnson, Utah Lepidopterists Society)
distribution in Canada British Columbia only (CBIF)