Koster (2010) (1) and Hodges (1962) (3) both note that Cosmopterix fernaldella, C. ebriola, and C. scirpicola cannot be separated without dissection. However, range may be useful in eliminating possibilities. See comments here.
Contributed by Kyhl Austin on 16 December, 2016 - 7:11pm Additional contributions by Steve Nanz Last updated 18 December, 2016 - 8:50pm
Disclaimer: Dedicated naturalists volunteer their time and resources here to provide this service. We strive to provide accurate information, but we are mostly just amateurs attempting to make sense of a diverse natural world. If you need expert professional advice, contact your local extension office.