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Species Hydraecia micacea - Rosy Rustic - Hodges#9514

Rosy Rustic Moth? - Hydraecia micacea A Noctuid sp. - Hydraecia micacea Larva - Hydraecia micacea - Hydraecia micacea Larva - Hydraecia micacea - Hydraecia micacea Noctuid IMG_4484 - Hydraecia micacea Noctuid IMG_3879 - Hydraecia micacea Hydraecia micacea Noctuidae: Hydraecia micacea - Hydraecia micacea
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 Noctuidae (Owlet Moths)
Subfamily Noctuinae (Cutworm or Dart Moths)
Tribe Apameini
Genus Hydraecia
Species micacea (Rosy Rustic - Hodges#9514)
Hodges Number
Other Common Names
Potato Stem Borer (larva)
wingspan 28-45 mm (UK Moths); 32-40 mm (Charles Covell)
larvae to 40 mm
Adult: forewing light to medium brown with dark brown shading in lower median area; PM line very slightly arced (almost straight) except for sharp inward bend near costa; AM line composed of 2 arcs: small one at costa, and much larger one crossing 2 veins and extending to inner margin; ST line wavy, often indistinct, with darker shading beyong it; terminal line slightly wavy
hindwing pale shiny brown with gray veins, median line, and arced discal spot

Larva: body pinkish or pale purple with dark band across each abdominal segment
Newfoundland to Massachusetts, west to Ontario and Wisconsin; spreading southward and westward
fields, waste places, grassy or weedy borders of corn fields
adults fly from late July to September
larvae bore in stems of dock (Rumex spp.), burdock (Arctium spp.), plantain, potato, tomato, grasses, and many other low plants; can be a pest in corn fields
Life Cycle
one generation per year; overwinters as an egg which hatches in May; young larvae bore in stems of grass and weed seedlings, then migrate to larger plants such as corn as they mature; pupation occurs in surface soil in July; adults emerge in late July or early August; in September, 50-75 eggs are laid in parallel rows on leaf sheaths of grass, especially Quack Grass
A European species introduced to maritime Canada in the early 1900s
See Also
Hydraecia perobliqua forewing lacks dark brown shading in lower median area, has a straight PM line with beveled angle near costa, and AM line composed of 3 fairly equal arcs.
H. immanis (Hop Vine Borer) is larger (wingspan to 55 mm), forewing more pinkish-brown and lacks dark brown shading in lower median area, PM line bent above middle, and AM, PM, ST lines double

Compare images of all 3 species

Nephelodes minians and Lacinipolia lorea are also superficially similar.
Internet References
live adult images plus food plants and common name reference [Rosy Rustic; adult] (Ian Kimber, UK Moths)
live adult images (Moths and Butterflies of Europe & North Africa)
live adult image (Hants Moths, UK)
live adult image (Josef Hlasek, Czech Republic)
food plants plus links to live and pinned adult images (Markku Savela, FUNET)
distribution plus biology, damage, control methods, common name reference [Potato Stem Borer; larva] (Agriculture Canada)
food plants plus biology, control methods (U. of Vermont)