Location: Applewood, Golden, Colorado
July 25, 2011
Daniel,
Thank you so much for the speedy reply. It really made Hannah’s day!
Here is the drawing that she made to save for her bug journal.
We catch, study and release a lot of Swallow Tail Butterflies in our back yard too (see second pic). Is there a similar trick to determining the sex of that species?
Thanks again,
Charley
Hi again Charley and Hannah,
This is a male Two Tailed Swallowtail, Papilio multicaudata. According to bugGuide: “Upper surface of male forewing with narrow black stripes. Each hindwing has 2 tails.(1) If abdomen is visible, male claspers are obvious as a yellow segment at the tip, beyond the black stripe. Females often have broader black stripes, and more blue on the upperside.” The narrower stripes and limited blue indicate that this is a male.