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Species Idia aemula - Common Idia - Hodges#8323

Common Idia - Hodges#8323 - Idia aemula Idia aemula - Hodge's #8323 - Idia aemula Common Idia  - Idia aemula Moth 1 - Idia aemula A Noctuid Moth - Idia aemula Common Idia - Hodges#8323 - Idia aemula Idia aemula NJ April - Idia aemula Common Idia? - Idia aemula
Show images of: caterpillars · adults · both
Kingdom Animalia (Animals)
Phylum Arthropoda (Arthropods)
Subphylum Hexapoda (Hexapods)
Class Insecta (Insects)
Order Lepidoptera (Butterflies and Moths)
Superfamily Noctuoidea (Owlet Moths and kin)
Family Erebidae
Subfamily Herminiinae (Litter Moths)
Genus Idia
Species aemula (Common Idia - Hodges#8323)
Hodges Number
Other Common Names
called Waved Tabby in Europe
Synonyms and other taxonomic changes
Idia aemula Hübner, 1814
Epizeuxis aemulalis Hübner, 1821
Herminia concisa Walker, 1860
Homoptera herminoides Walker, 1860
Microphysa mollifera Walker, 1858
Camptylochila undulalis Stephens, 1834
wingspan 20-30 mm
Adult: forewing reniform spot large, pale, conspicuously contrasting against ground color of wing; lines thin and not obviously thicker/darker at costa; dark shading in median area (if present) does not touch proximal edge of PM line at inner margin
most of North America and Eurasia
adults fly from May to October in the north; April to November in the south
larvae eat dead leaves
See Also
Idia concisa of authors, not (Walker, 1860) - "Idia aemula is probably a complex of 5-10 species, one of which is what is called concisa.” - Hugh McGuinness (pers. comm. 1/10/2018). This seems supported by DNA barcoding. However, if ‘concisa’ is not aemula, then it’s probably at least two good species. Based on barcode, having a forewing with dark medial bar and/or a contrastingly pale hind wind wing will separate most specimens from Idia aemula but it is far from conclusive. - Steve Nanz (4/11/2020)
American Idia (I. americalis) forewing has heavy dark marks along costa
Toothed Idia (I. denticulalis) forewing dark patch in median area touches proximal edge of PM line at inner margin, and reniform spot is small and indistinct (compare images of both species at CBIF)
also see images of ten other Idia species at MPG
Print References
Covell, p. 322, plate 41#12 (1)
Internet References
adult images (Larry Line, Maryland)
common name reference plus flight season and larval food (Ohio State U.)
distribution in Canada list of provinces of occurrence (U. of Alberta, using CBIF data)