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Papilio Sp576 - Papilio appalachiensis - male

Papilio Sp576 - Papilio appalachiensis - Male
Promised Land State Park, Pike County, Pennsylvania, USA
May 29, 2004
Possibly Papilio canadensis but I think P. glaucus is a better match. Perhaps both. Time of year and range appear OK for both. Intergrades?

For what it's worth, I don't recall ever seening Eastern Tiger Swallowtail feeding at dung before. A Google and Bugguide search found the behavior only among Canadian Tiger Swallowtail.

Images of this individual: tag all
Papilio Sp576 - Papilio appalachiensis - male Papilio Sp576 - Papilio appalachiensis - male

It dawns on me
That these two photos would be much more obvious and easily used for comparison if they were posted with P. appalachiensis (where the others from Pennsylvania that look similar are posted). The comparison with P. glaucus in these photos is quite nice, but loosing these in a see of dozens of P. glaucus photos seems pointless.

There is still the debate as to whether these should be called P. canadensis or P. appalachiensis. I suspect that they are one species, the ones in Pennsylvania being in at an intermediate point on the transition from one into the other.

Moved from Eastern Tiger Swallowtail.

This is indeed a mixed party
There are two different things here. Whether there are intermediates among them I can't say. In this photo, the one on the right (that you can see most of the top of) and the one in the center are P. glaucus. The other four are of the P. canadensis / appalachiensis ilk. There are others much like this on BugGuide.

Pike County is "officially" in "P. canadensis" country, and those in the eastern part of Pennsylvania are usually recorded as such. However, they are starting to look a lot like the very similar (but larger) P. appalachiensis from further south here, and those in southwestern Pennsylvania are actually being called P. appalachiensis now.

Who's Who?
I got the impression that in the other photo you described the one left and above center as P. glaucus not the one in the center. The individuals have moved around a bit so I may have this wrong.

I'm trying to understand the differences and am very confused by the descriptions I'm reading. There seem to be many misplaced images in the guide based on my understanding. So as it stands, I can't even tell who's who in my own photos.

I see your point
P. glaucus are the one on the right wings open and the upper left one of the two in the center - with the wings more folded. If you look at the submarginal spots on both top and bottom on these two, you can see that they are shaped differently (more separated below, and more rounded above and below). There are other differences which come across to give a different "look" but it's hard to quantify all of them. There is suspicion that the two occasionally hybridize as well, so that could add a twist (but these particular ones look like either one or the other). Some people just look at them and say "they're all the same thing", but I can see a difference myself (and I'm a skeptic of most "splitting" that has been going on in recent years).

That's what I thought. Thanks!

Moved from Papilio.

Attempting to 'tidy-up' the butterfly pages
Thus am moving this to Eastern; locality seems a little too far east for Canadian and the guy dead center, ventral view, is an Eastern.

Those dung-feeding swallowtails
Interesting observations. I've seen Eastern Tiger Swallowtails (P. glaucus) feeding on goose poop down in the lowlands of North Carolina. I'll find that photo and post it.

I also have a photo from years ago in the NC mountains, of one of these swallowtail species clustered around a spot--perhaps feeding on dung. I'll have to post that too--maybe those were Canadian Tigers.

Patrick Coin
Durham, North Carolina

Eastern Tigers on dung

Patrick Coin
Durham, North Carolina

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