Subject: Tiger Swallowtail?
Location: Southern Oregon
July 14, 2012 2:04 pm
Found these on the side of Mt. Ashland, Siskiyou Mtns. yesterday at about 5000’ elev. One’s a bit different than other tiger swallowtails in color and maybe a bit smaller.
The other is a blue, but what sort?
We were uncertain at first if this was an Anise Swallowtail, Papilio zelicaon, or an Old World Swallowtail, Papilio machaon, because they look so similar. To further complicate matters, both species have dark and yellow forms. We learned in Jeffrey Glassberg’s book Butterflies Through Binoculars, the West, that the Anise Swallowtail can be distinguished from other similar looking swallowtails because of the “black spot at HW outer angle is small and centered” within the orange spot. This was verified on BugGuide which states: “Upper surface of hindwing has yellow-orange eyespot near tail with round black center that is not connected to hindwing margin.” We are uncertain of the identity of the Blue, but perhaps one of our readers will be able to supply an answer. We suspect it is either an Azure (see BugGuide) or one of the Arctic Blues (see BugGuide). Your photos are both quite lovely and detailed.
If by Old World Swallowtail is meant Europe or such, then this was an Anise Swallowtail b/c the picture was taken in southern Oregon. I am clueless about the blues but I know there are a bunch of them.
Thanks for the kind words about the photos. My wife says they’re already posted to whatsthatbug.com. Thanks so much for id’ing these two. Great site!
Hi again Terry,
The Old World Swallowtail is established in western North America, but it is originally from Eurasia.
Thanks! I guess I never thought about someone importing butterflies. BTW – I made a donation to WTB. You guys deserve it!
Hi again Terry,
We are not certain how the Old World Swallowtail was introduced to the New World. We suspect it was an accidental introduction on plants that were brought from Europe to grow on American soil. That was very kind of you to make a donation. See these BugGuide categories for the subspecies of the Old World Swallowtail and the Anise Swallowtail.
Subspecies Papilio machaon bairdii – Baird’s Swallowtail http://bugguide.net/node/view/229640
Subspecies Papilio machaon oregonius – Oregon Swallowtail http://bugguide.net/node/view/229641
Subspecies Papilio zelicaon nitra – Anise Swallowtail http://bugguide.net/node/view/45385
Subspecies Papilio zelicaon zelicaon – Anise Swallowtail http://bugguide.net/node/view/284100