|scientific name Catocala junctura |
common name Joined Underwing
In Alberta, riparian cottonwood-willow groves in the valleys of the arid southern grasslands region.
Adults fly in Alberta in late August and early September.
One of the largest (7.2- 8.5 cm wingspan) Alberta underwing moths. The forewings are a smooth evenly powdered blue-grey, with few markings. The doubled reniform spot and the lower end of the postmedian band where it crosses the fold are the most prominent markings. The hindwings are salmon or orange-pink as in parta and luciana, not red-orange as in unijuga and meskei or bright pink as in hermia and concumbens. The hindwing black median band is narrow and turns in sharply at the lower end, and in some specimens may have a small separate spot at the lower end as does C. meskei. The fringe is white and the antennae are simple, and both sexes are essentially alike.
The adults are one of the latest Alberta underwings to appear. They are nocturnal and come to light, but like other underwings are best caught using sugar baits. The eggs overwinter, and the larvae are solitary defoliators. There is a single brood each year.
At the northern edge of its range. No serious concern.
No Alberta data. Elsewhere reported to use willow (Salix).
New York and Pennsylvania west to southeastern British Columbia, Montana, Colorado and Arizona, north to extreme southern Alberta and Saskatchewan. In Alberta it has been taken in the Milk River and Oldman River valleys, north to Taber.
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