Garden butterflies

I've seen lots of butterflies in our garden recently. Most are familiar visitors, and always welcome. But I've needed to remind myself recently of the differences between two of the 'regulars' -- tiger and black swallowtails. They belong to a mimicry group of butterflies that mimic pipevine swallowtails.

Male tiger swallowtail

Male tiger swallowtails are yellow with black stripes, but females are either yellow, with blue on the hindwing, or dark, also with blue spots on the hindwing.

It's telling the dark females apart from some of the other dark swallowtails that's harder. Hmm, I see from my Kaufman guide that there's a good bit of variation in the tiger female's dark morph, just to complicate things. But distinguishing black swallowtails to dark tiger females is easy if you get a good look at the lower side of the wing and how it's banded with orange, and then get a good look at the upper wings (easier said than done).

Check out a wonderful butterfly site that I just found at the Massachusetts Butterfly Club, a chapter North American Butterfly Association -- it has a wonderfully useful side-by-side comparison feature, with LOTS of images of each species. Wow. That one is being bookmarked!