Other Common Names
Aspen Twoleaf Tier (larva)
Synonyms and other taxonomic changes
Enargia decolor (Walker, 1858)
Mythimna decolor Walker, 1858
* phylogenetic sequence #932674
Wingspan 30-40 mm.
Larva to 32 mm (Comstock, 1937).
Pupa 19 mm (Comstock, 1937).
Adult: forewing yellowish with light reddish-brown speckling; AM and PM lines brown, distinct; AM line with sharp angle in middle; orbicular and reniform spots solid yellowish; no dark spot at lower end of reniform spot (a diagnostic feature); brown band on either side of reniform spot forms a shallow "V" in median area; hindwing cream-colored with faint grayish subterminal band.
British Columbia to Nova Scotia, south in the east to Ohio, south in the west to California.
Woodlands, parks, river flood plains where hostplants grow.
Adults fly from July to September. Larvae present from May to August.
Larvae feed on leaves of poplar (Populus
spp.). Comstock found them feeding on quaking aspen
) in the Arizona mountains.
Newly-hatched larvae begin feeding on inner side of rolled-up leaf, then feed on outside; older larvae construct flattened cases made from two leaves bound together with silk webbing (hence the name Twoleaf Tier); fully mature larvae fall to the ground and pupate; overwinters as an egg; one generation per year.
) forewing reniform spot has dark spot at lower end, lacking in E. decolor
; Lesser Eyed Sallow
) forewing has indistinct markings, is less yellow/more brown, and has dark spot at lower end of reniform spot (compare images
of all 3 species at CBIF)
Comstock, J. A. 1937. Miscellaneous notes on western lepidoptera. Bull. Southern California Acad. Sci. 36(1): 21
Powell, J. A. & P. A. Opler 2009. Moths of Western North America. pl.54.29m, p.300 (1)
live adult images
plus description, foodplants, flight season (Lynn Scott, Ontario)
presence in California; list
of 2 specimen records with dates and locations (U. of California at Berkeley)
distribution in Canada; list
of provinces of occurrence (U. of Alberta, using CBIF data)