The range of the Luna Moth, (Actias luna), a large, beautiful Santurniidae is not known to extend as far East as Utah. I have read though, (trying to find the reference) that they are sometimes found as far East as middle Montana which would be about the same longitude as eastern Utah.
I lived for many years in Uintah county. On two separate occasions a few years apart, I found one of them clinging to my house below the porch light. This spring and summer I’ll be going back attempting to collect them and document that their range does in fact extend into Utah.
Though it has been several years, I believe there is a good chance for success. I know the area where I earlier observed them very well, and the habitat is still in pretty much the same shape today as it was then.
Anyone care to join me?