Species Details

Sthenopis purpurascens

University of Alberta E.H. Strickland Entomological Museum Read more about this collection »

SeasonalityAdults fly in Alberta from early July through mid-August, peaking the last half of July. IdentificationAdults are large (6.6-10.0 cm wingspan) long-winged moths that occur in two color forms, purple-grey and yellow-brown. Until recently the yellow-brown form was thought to be a separate species, S. quadriguttatus. The forewings have a darker oblique median band, a darker terminal area and darker spots along the costa. There are two small, silver spots near the wing base. Hindwings are even purple brown or salmon pink, unmarked except for one or two small spots on the outer part of the leading edge. The antennae in both sexes are greatly reduced and hair-like, and separate them from all other large Alberta moths. The similar S. argenteomaculatus (Harris) does not occur in Alberta, and the literature reports for argentomaculatus are errors (Schmidt and Lawrie, 1999).

Scientific Name Sthenopis purpurascens Seasonality Adults fly in Alberta from early July through mid-August, peaking the last half of July. Identification
Adults are large (6.6-10.0 cm wingspan) long-winged moths that occur in two color forms, purple-grey and yellow-brown. Until recently the yellow-brown form was thought to be a separate species, S. quadriguttatus. The…
Adults are large (6.6-10.0 cm wingspan) long-winged moths that occur in two color forms, purple-grey and yellow-brown. Until recently the yellow-brown form was thought to be a separate species, S. quadriguttatus. The forewings have a darker oblique median band, a darker terminal area and darker spots along the costa. There are two small, silver spots near the wing base. Hindwings are even purple brown or salmon pink, unmarked except for one or two small spots on the outer part of the leading edge. The antennae in both sexes are greatly reduced and hair-like, and separate them from all other large Alberta moths. The similar S. argenteomaculatus (Harris) does not occur in Alberta, and the literature reports for argentomaculatus are errors (Schmidt and Lawrie, 1999).
Life History
Females deposit eggs in the vicinity of the host while in flight. The larvae bore into the roots of poplars, willows or alder where they complete the life cycle. The larvae apparently take two years to complete the…
Females deposit eggs in the vicinity of the host while in flight. The larvae bore into the roots of poplars, willows or alder where they complete the life cycle. The larvae apparently take two years to complete the lifecycle, and adults in Alberta are more common in odd-numbered years. Mature larvae are about 50-60 cm long, with cream-white bodies, brown heads and brown bases of the setae. The adults are crepuscular and are poorly attracted to light.
Conservation A fairly common, widespread insect; no concerns. Diet Info Larvae bore into the roots of poplars (Populus sp.), and to a lesser extent willow (Salix) and alder (Alnus). Range
Labrador and New York north and west to British Columbia and the Northwest Territories, south in the mountains to Arizona. In Alberta, it is most common throughout the Boreal forest and Aspen Parkland regions, less…
Labrador and New York north and west to British Columbia and the Northwest Territories, south in the mountains to Arizona. In Alberta, it is most common throughout the Boreal forest and Aspen Parkland regions, less common in the Foothills and Mountains, and along wooded parts of the valleys in the Grasslands region.
Sthenopis purpurascens
Sthenopis purpurascens

Taxonomic Hierarchy

Kingdom Animalia Phylum Arthropoda Class Hexapoda Subclass Insecta Order Lepidoptera Suborder Exoporia Superfamily Hepialoidea Family Hepialidae Subfamily Hepialinae Genus Sthenopis Species Sthenopis purpurascens
This hierarchy is created from our museum records, it may not always accurately reflect modern taxonomies.

Taxonomic Hierarchy for University of Alberta E.H. Strickland Entomological Museum