Distinguishing Swallowtail Butterflies
—and one mimic.
I am not a person who can readily identify birds, dragonflies, or butterflies “on the wing”, at least at first. I need to take pictures, and then sit down with a series of guide books to try to figure out species. But just flipping pages between the species accounts can give me trouble matching up distinguishing marks — I forget what one looked like while looking at another. I need comparison charts!
I see swallowtail butterflies here usually in August and September, just one or two at a time. They are hard to photograph because they seem to see me coming with my camera and they flutter off. The Giant Swallowtail and yellow Tiger Swallowtail are easy to identify —
The swallowtails that are black with blue coloring are harder for me to keep straight, and added to this mix is a swallowtail mimic, the Red-spotted Purple (which has no red and no purple, only blue and orange). So here is a little cheat sheet, and you can click on any picture to see it larger.
Pipevine Swallowtails can appear plain black or iridescent blue, depending on the angle of the light. These two photos were taken of the same butterfly as the Pipevine in the cheat sheet above, an hour later, so the light was a little different.
Two butterfly books that I use often are Butterflies of Houston and Southeast Texas by John and Gloria Tveten (1996, University of Texas Press), and the Audubon Society Field Guide to North American Butterflies (1981, Alfred A. Knopf, Inc.).