In cities, white butterflies are a common sight in our gardens.  Almost always these are cabbage whites, a very adaptable worldwide crop pest that's proven hardy in the insecticide-laden landscapes of alien plants that don't support our native butterfly species.  But get up to the mountains, and something unexpected happens.  There are still white butterflies, but look closer and one notices they are larger with beautiful red spots and black patterning on the wings.  These are parnassians, one of the oldest known butterfly types.  Parnassians diverged from other butterfly subfamilies that evolved into our modern swallowtails in the Cretaceous period, between 66 million and 145 million years ago.  

Parnassians are toxic to birds and the red spots may be a warning.  They also have a labored flight, making them a bit easier for photographers to keep up.  Most of the time butterfly photos include a flower, a darker background if flash is used, or green foliage.  It's a nice surprise to find a more unusual setting for this Clodius Parnassian, resting on a wooden bridge deck on the way to Washington's Silver Star Mountain.  The bridge was later washed out and replaced with a concrete one, demonstrating the value of seizing the moment.  

This butterfly is a female.  After mating, the male places a waxy cover called a sphragis over the female's abdomen that prevents mating again and this individual has one.  While not easy to see in the photo above, it's well defined in any size print from the original film.  

Click here to see a list of plants for attracting butterflies to your garden in the Portland, Oregon area and Columbia Gorge.