Adult: forewings white, with gray or grayish brown scaling; basal area gray or grayish brown, extending outwardly along inner margin to middle of wing; maculation similar to that of personaria but with posterior, elliptical lobe of median area tending to be larger, and with t.p. line irregular in course, not inwardly dentate; median area outlined by prominent white band; discal dash white, elongate, prominent; subterminal and terminal areas concolorous; terminal line varying from absent to complete, narrow, dark brown; fringe white, brown opposite vein endings. Hind wings white, with variable number of pale grayish brown scales; maculation absent in most specimens, some with small discal dot and trace of dark subterminal area; terminal line as on forewings; fringe white, some specimens with small amount of brown scaling opposite veins.
[excerpt of description by Frederick Rindge, copied from PDF doc cited below]
Southeastern British Columbia to southwestern Saskatchewan, south to California(1)
and central Texas, and into Mexico.
Moth Photographers Group
- large map with some distribution data.
Varied, mostly arid and semiarid environments such as desert grasslands and mountians, sagebrush flats, short grasslands, and prairie badlands; adults are nocturnal and come to light.
Adults fly from February to September in the south; May to August in the north (Alberta). They are most commonly seen (often in large numbers at lights) in spring.
Larval foodplant unknown but presumed to be wormwood (Artemisia sp.) - the same as that of a sister species Plataea personaria.
Presumed to be one generation per year, even in the south where the flight season is long.
No other species of Plataea is so boldly marked.
species are shades of red and brown, and live in coniferous forests - not in open sagebrush habitats
Powell, J.A. & P.A., Opler 2009. Moths of Western North America
. University of California Press. p. 218, pl. 30.23.(2)
Rindge, F.H., 1976. A revision of the moth genus Plataea
(Lepidoptera, Geometridae). American Museum Novitates
including pinned adult image by G.G. Anweiler, common name reference, habitat, flight season, description, presumed foodplant, distribution (Strickland Entomological Museum, U. of Alberta)
presence in California
list of 16 specimens with dates and locations (U. of California at Berkeley)
distribution in Canada
list of provinces (CBIF)