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Species Polia nimbosa - Stormy Arches - Hodges#10275

caterpillar (Noctuinae) - Polia nimbosa Moth - Polia nimbosa stormy arches - Polia nimbosa Stormy Arches Moth - Polia nimbosa Noctuidae: Polia nimbosa - Polia nimbosa 10275 – Polia nimbosa – Stormy Arches - Polia nimbosa Polia nimbosa, I think - Polia nimbosa Stormy Arches - Polia nimbosa
Show images of: caterpillars · adults · both
Classification
Kingdom Animalia (Animals)
Phylum Arthropoda (Arthropods)
Subphylum Hexapoda (Hexapods)
Class Insecta (Insects)
Order Lepidoptera (Butterflies and Moths)
Superfamily Noctuoidea (Owlet Moths and kin)
Family Noctuidae (Owlet Moths)
Subfamily Noctuinae (Cutworm or Dart Moths)
Tribe Hadenini
Genus Polia
Species nimbosa (Stormy Arches - Hodges#10275)
Hodges Number
10275
Synonyms and other taxonomic changes
Polia nimbosa (Guenée, 1852)
Eurios nimbosa (Guenée, 1852)
Aplecta nimbosa Guenée, 1852
Phylogenetic sequence # 932867
Explanation of Names
NIMBOSA: from the Latin "nimbus" (rain cloud; storm cloud); probably refers to the dark mottling on the forewing, reminiscent of the color of a storm cloud, and the origin of the common name Stormy Arches
Numbers
Lafontaine & Schmidt (2010) listed nine species of the genus Polia in America north of Mexico. (1)
Size
Wingspan 40-65 mm.
Forewing length length 23-27 mm. (2)
Identification
Adult: tegulae ("shoulder pads" on thorax) pale with black margins; forewing pale gray, mottled with gray and black; orbicular, claviform, and reniform spots with sharp black outlines; reniform spot strongly curved; AM and PM lines double, scalloped; PM line resembles a sinuous series of connected white chevrons; ST line jagged, and has two small black spots near anal angle (the spots are either side-by-side or joined, and are a distinctive feature).
hindwing grayish or brownish; median line, originating near anal angle, bordered distally by pale band, followed by dark band along outer margin.
Crumb (1956) has description of the larvae. (3)

Larva: very similar to Lachinipolia lorea 10405. Polia nimbosa has a faint spiracular line but Lachinipolia doesn't. There seems to be a ridge across the back of A8 on Polia but not on Lachinipolia. The spiracles on Polia are supposed to be tan with a black rim. The head of Polia has a light center with dark lines down the face.
Range
coast to coast in northern United States and southern Canada (Newfoundland to North Carolina, west to northern California(4), north to British Columbia)
Season
The flight period appears to be May to September with the peak in July. (5)
Food
larvae feed on leaves of alder, birch, gooseberry (Ribes spp.), huckleberry (Gaylussacia spp.), maple, willow
Life Cycle
one generation per year
See Also
Cloudy Arches (Polia imbrifera) forewing has a less distinct PM line, a more noticeable whitish ST line, and a relatively large triangular dark patch near anal angle (rather than two small black dots set side-by-side, as in P. nimbosa)
Polia propodea has dark "shoulder pads" (tegulae), a darker gray forewing with a distinct blackish ST line, and two tiny white spots in lower corner of reniform spot - lacking in P. nimbosa
(compare images of all three species at CBIF)
Print References
Guenée, 1852. Noctuidae II. pp. 77, 769.
Powell, J.A. & P.A. Opler 2009. Moths of Western North America. University of California Press. plate 55, fig. 25; p. 303. (6)
Internet References
live adult images plus description, food plants, flight season (Lynn Scott, Ontario)
pinned adult image by John Glaser, plus food plants (Larry Line, Maryland)
pinned adult images of male and female (James Adams, Dalton State College, Georgia)
distribution in Canada list of provinces (U. of Alberta, using CBIF data)
Works Cited
1.Annotated check list of the Noctuoidea (Insecta, Lepidoptera) of North America north of Mexico.
Donald J. Lafontaine, B. Christian Schmidt. 2010. ZooKeys 40: 1–239 .
2.Pacific Northwest Moths
3.The Larvae of the Phalaenidae [Noctuidae]
Samuel Ebb Crumb. 1956. U.S. Department of Agriculture Technical Bulletin 1135: 1-356.
4.Essig Museum of Entomology, California Moth Species List
5.North American Moth Photographers Group
6.Moths of Western North America
Powell and Opler. 2009. UC Press.
7.BOLD: The Barcode of Life Data Systems