Dragonflies, Butterflies & Spiders

In the interest of getting better aquainted with some of the insect life I often see while I'm out, I bought one of the National Audubon Society's field guide to insects & spiders. I have been photographing insects (usually dragonflies, butterflies and spiders) from time to time as I see them but until two days ago was not able to identify them. As with birds, there are subtle variances that can make identification tricky.

Yes, I know they're not birds, but at least two of the three have wings (I'm glad spiders don't have wings)! I have included here three I saw over the weekend. I understand that the ID of the Pearl Crescent butterfly is in some doubt as there is a similar species that can only be told by genetic testing (something I do *not* have access to!).

Of the two dragonflies (which are both "skimmers") the one with plain wings except dark patches towards the body is a female Widow Skimmer and the other is a female Common Whitetail skimmer. After quickly realising that the field guide didn't have all the insects I was looking for (it typically only shows the male *or* female of each species), I went on-line to find a reference. The best one I found (and where I ID'd these dragonflies) was Digital Dragonflies. If anyone knows of a good site for ID'ing butterflies, I would appreciate hearing from you! I found that both wing *and* body color were important when ID'ing them.