Two-Tailed Tiger Swallowtail (Pterourus pilumnus)

The two-tailed swallowtail is one of the largest and most beautiful of the yellow tiger swallowtail family. We found the larva of this butterfly on ash trees when I worked in Denver Colorado for a summer The range across the rockies and to parts of the central U.S.

Click on any of the thumbnails to get a larger picture.

Clicking on the picture to the left will give a larger version of the above picture.

To the left is a second instar and an egg. And to the right is a first and third instar (the first instar does not show up well). Early instars look much like bird droppings, a common form in swallowtail larva.

Some of the third instars have a more greenish appearance, as shown on the left. Fourth instars (picture on right) have a much different appearance. Note that the eye spots are false. The actual head is tucked under the front part of the body in this picture.

Fifth instars have the same appearance as fourth. Again, the actual head is tucked under th front of the body. The false eyespots help ward of predators by making them think the head is bigger than it actually is. Note the brilliant blue dots along the body and "neck" in this photo. The pupa looks like just about any swallowtail pupa.

Address questions or comments to: Scott Henninger, scotth#cse.unl.edu (to prevent automated SPAM systems, I have replaced the normal '@' symbol - just put it back in to send a message)

	Clicking on the picture to the left will give a larger version of the above picture.
	To the left is a second instar and an egg. And to the right is a first and third instar (the first instar does not show up well). Early instars look much like bird droppings, a common form in swallowtail larva.
	Some of the third instars have a more greenish appearance, as shown on the left. Fourth instars (picture on right) have a much different appearance. Note that the eye spots are false. The actual head is tucked under the front part of the body in this picture.
	Fifth instars have the same appearance as fourth. Again, the actual head is tucked under th front of the body. The false eyespots help ward of predators by making them think the head is bigger than it actually is. Note the brilliant blue dots along the body and "neck" in this photo. The pupa looks like just about any swallowtail pupa.