Black and Yellow Butterfly - Papilio machaon

definitely not Papilio zelicaon

Hi Lana,
This is a Baird's Swallowtail - Papilio bairdii. The classification used here lumps it under Papilio machaon. The yellow abdomen (on yellow-winged individuals) is one good clue. The narrower more pointed front wings, more yellow on the hind wing, larger marginal yellow spots, etc. are all clues. The larvae usually feed on Composites (mostly Artemisia dracunculus) instead of Umbellifers, but that you can't see in a photo of an adult :)

The Oregon Swallowtail (a subspecies of P. bairdii or of P. machaon, depending on your author of choice) is very similar, but has even more yellow. It is on the west side of the Rockies. Subspecies dodii occurs a bit further north, and meets subspecies bairdii in Montana (hard to say where one stops and the other begins).

Baird's Swallowtails are related to Anise Swallowtails, but they are not too difficult to tell apart once you get to know them.

Oh, almost forgot, this one is male. You can tell claspers at the tip. The fat abdoment makes it look female, and that faked me out.

Moved from Butterflies.

… David J. Ferguson, 19 November, 2008 - 12:42am

Anise swallowtail?

Looks close, range is right, I'm uncertain. A couple references:
http://www.butterfliesandmoths.org/species?l=1363&chosen_state=30*Montana

Note also that there's at least one other color form for this butterfly.

… Ron Hemberger, 30 July, 2008 - 7:54pm

Maybe . . .

O.K., I do see the resemblence, BUT with one major exception. There is only a very slight hint of any blue spots on my specimen, barely visible on photo number one. All of the photos I've come across of the Anise, whether male or female, have prominent blue spots. I bet you are right, though, it definitely matches up better than anything else I've seen. Thanks!

… Lana Smith, 30 July, 2008 - 8:39pm

"Maybe" was my take, too.

Another possibility is a hybrid. My friend, a local butterfly expert, believes this is one:

… Ron Hemberger, 30 July, 2008 - 9:01pm

A Probable Anise

HI, Ron, and thanks for the comments. Tell me more about the other color form of the Anise, and also the differences between males and females. I notice mine has a nearly solid colored abdomen, while yours has bold stripes. And there's that bothersome absence of blue dots on the hind wings . . . by the way, your photos are beautiful. Mine were a little underexposed, and I wonder if that is why the blue dots don't show up so well. Although I don't remember them being at all noticeable in real life, either.

… Lana Smith, 30 July, 2008 - 9:47pm

Yours is a worn specimen, and I think that's the explanation

- I don't think it's different enough to be considered a possible hybrid. The blue scales are only on the surface of the wing and so when color begins to go with wear and tear, those would be among the first areas to disappear, but even so, as you say there is still some blue visible on this image. As for body color, the width of the stripes appears to be somewhat variable - here's one more like yours

… Hannah Nendick-Mason, 31 July, 2008 - 1:44pm

I'm convinced

Thanks for your help, Ron and Hannah. Unfortunately, I don't see too many of these larger butterflies in my yard, although I always plant colorful flowers for them. I believe the tattered edges of the wings and faded color is what threw me off, but I am going to consider it an Anise Swallowtail.

… Lana Smith, 31 July, 2008 - 2:38pm

About as far as I can go.

I'm no expert, and most of what I've done here is cursory research, blended with a little personal knowledge. Here's the other color form:

I think you have what I call a "batterfly", so some color could be lost, as it became aged and worn.

Wish I could be more help.

… Ron Hemberger, 30 July, 2008 - 10:58pm