Synonyms and other taxonomic changes
Acronicta interrupta Guenée, 1852
Adult - forewing light to medium gray; basal dash ends in 3 prongs with top prong turning toward costa as part of AM line; anal and subapical dashes present; cross-lines (except PM line) incomplete and indicated mainly by black marks along costa; orbicular spot pale with thin dark outline, reniform spot consists of dark marking on basal side; PM line complete, s-shaped, usually double and filled with white; fringe checkered with dark scales between veins hindwing in male dirty white, darkening near outer margin and along outer veins; hindwing in female light gray with faint PM band.
Larva - Red, white, and blue-gray, immediately recognizable by its paired middorsal red spots: A1-A7 with red dorsal spots that may fuse, especially rearward. These spots embedded in prominent, shiny, black dorsal patches. Broad, frosty white to cream subdorsal stripe. Dorsum of A8 swollen, smoky, bearing wartlike setal clusters. Subdorsal and lateral pinacula only modestly raised and frequently yellowed. Setae long; orange over dorsum and mostly white along sides. Head dark reddish brown to black with or without red patch over each vertex and white rays running through cheek. Larva to 4 cm
Nova Scotia to Florida, west to Arkansas and Colorado, north to Saskatchewan (and Alberta: one record)
dry deciduous woodland edges and tall shrub areas
adults fly from April to August/September
larvae feed on leaves of apple, apricot, birch, cherry, crabapple, elm, hawthorn, Hop-Hornbeam (Ostrya virginiana), mountain-ash (Sorbus spp.), oak, plum, willow
two or more generations per year in the south; one in the north
Ochre Dagger (A. morula) has orangish markings on thorax and forewing; Nondescript Dagger (A. spinigera) has a double AM line, a black-outlined orbicular spot, and a pale purplish tint to the forewing.
Larva - larva of Acronicta quadrata, a aboreal species, is similar. Its caterpillars are more boldly marked with little red on A1, bear larger red patches over A5-A7, and sport a broader subdorsal stripes
pinned adult image
(John Glaser, Maryland)
, distribution, habitat, food plants (U. of Alberta)