Beautiful!

I believe it's a rose swallowtail, a widespread butterfly of Asia that uses aristolochia as a host plant, like our pipevine and polydamus swallowtails. The caterpillar looks like them, too.
'Must be something about that plant that makes for beautiful butterflies!

And it's nectaring on some type of liatris. Most eastern American plants have a counterpart in Asia. I suppose at one time the two continents were linked, you know that one big continent, forget the name.

Sherry

Here is a link that might be useful: Rose Swallowtail

Just beautiful! I think that might be an agastache (hyssop) that is feeding on.

Pangaea (super-continent).

Pangaea - that's it, Larry!

And you're right, that's some type of agastache.

Sherry

â¢Posted by misssherry Z8/9SE MS (My Page) on
Tue, Mar 25, 14 at 11:35

â¢Posted by larry_gene USDA8b-OregonPDX (My Page) on
Tue, Mar 25, 14 at 22:40

Thank you so much. It turns out that their selection of hosting plants are very specific: very similar plants in the same genus are not all accepted.