I know to give alot of room, when identifying Crescents in the field. Pearl Crescent butterflies (Phyciodes Tharos) vary from individual to individual, and can give you fits, because some are so variable, enough to tempt you to think that you have found a unique one.
Have a look at this female. She was nectaring in the reserve meadow at the Jamestown Audubon Center in Jamestown, New York. It’s those mid-forewing bands that triggered my curiosity. Yellower than I’ve ever seen, they reminded me of Phaon crescents, though I know that they fly hundreds of miles south of Western New York.
Some of the mystery slipped away after referring to Cech and Tudor’s Butterflies of the East Coast. They caution: “Female mid-FW [forewing] band often slightly yellow-toned (but less so than in Phaon [crescent]).”
When I turn the page in Butterflies of the East Coast, our girl starts looking a bit like a female Tawny Crescent, at least to me. Well Jamestown was once their range, but Cech and Tudor sadly note that Tawnys have disappeared from western New York post-1970’s.
So there you have it, Crescents are very handsome butterflies, but one must allow for a great deal of variation, and it’s a whole lot easier if you are well-schooled in identifying these winged beauties.