Comprehensive DescriptionRead full entry
General DescriptionA medium-large (4.5-5.5 cm wingspan) moth with powdery grey forewings with darker markings and white hindwings. Forewings with the normal markings somewhat broken and blurred, the outer part of the postmedian line and a partial reniform spot most prominent. The orbicular spot a small, hollow ring. There is no basal dash. The anal "dagger mark" is blurred but obvious. The male hindwings are white with grey scales along the veins. The female is larger and is more heavily dusted with grey on the hindwings. Antennae in both sexes are simple. Most likely to be mistaken for the American Dagger Moth, which is darker grey-brown on both wings and has a doubled, white-filled postmedian line, or the Cottonwood Dagger Moth, which is smaller and has narrower wings with a basal dash on the forewings. This large grey heavy-bodied dagger-moth is fairly common and widespread in Alberta. The large, pale and poorly marked western populations of A. dactylina found in Alberta were until recently treated as a separate species, A. hesperida (Large Grey Dagger-moth). Both "species" were listed for Alberta by Bowman (1951). Occassional grey-black melanic specimens have been seen from the coast of BC.