|scientific name Catocala hermia |
common name Hermia Underwing
Mature riparian cottonwood stands along the valleys of the southern grasslands.
Adults are on the wing in August and early September.
A large (5.8-6.8 cm wingspan) moth with grey-brown or "clay-colored" forewings and bright pink hindwings. Hermia is one of the medium-sized underwing moths. The forewings are a rather light even grey or grey-brown, not powdery grey as in unijuga or meskei. The jagged antemedian line and sinuous postmedian line and the large doubled reniform stand out against the lighter background. The hindwings are a bright pink, crossed by an incomplete black median band and a wider black terminal band and white fringe. There are few dark hairs in the basal part of the hindwings, giving it a very clean, neat look. The similar sized C. meskei has grey powdery-looking forewings on which the lines are less contrasting, and red-orange hindwings. Some specimens of hermia greatly resemble C. luciana, which has a browner, broader forewings and orange hindwings. It can also be difficult to separate hermia from smaller specimens of C. semirelicta, which usually have grey, powdery forewings and a slightly more orange shade of pink on the hindwings.
Adults are nocturnal and come to light, but are much more common at sugar baits. They fly in late summer and early fall and lay the eggs, which overwinter. The larvae are solitary defoliators. There is a single brood each year.
A common moth. No concerns.
No Alberta data. Probably poplar and/or willow.
A western species, found throughout the Great Plains, from southern Saskatchewan and Alberta south and west to Texas, Arizona and California. In Alberta, it occurs mainly in cottonwood stands along the river valleys of the plains, north to the Red Deer region and west to the lower foothills in the Calgary and High River areas.
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