OK, I was wrong. I decided to check with Master Controller to see what opportunities are available to my sim, and found she's already done that one. It was so long ago, I had forgotten about it. It's not repeatable, so she won't be offered it again. I guess I'll just have to keep checking with the collection helper every night while she's sleeping. If I find them, I can wake her up and send her after them. So far, most of the insects I find with it in the night are cockroaches and others that are available during the day, and the yellow and green fireflies. She has never found a regular moth, either.