Identification
Confusion with Agonopterix walsinghamella on BugGuide has occurred for several years. The two species have several notable differences though:
-Agonopterix walsinghamella has mostly gray scaling with some red and black scales on the top of the thorax and head, while Agonopterix lythrella has mostly light brown scaling there with a lateral dark streak down the thorax visible in fresh specimens
-Agonopterix walsinghamella has two black spots (often very faint) in the forewing cell, while Agonopterix lythrella has the two spots combined into a bold stripe
-Agonopterix walsinghamella has has relatively elongate forewings, while Agonopterix lythrella has relatively shorter/stubbier wings
Food
Loosestrife and Saint John's Wort
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