Saturday, October 07, 2006

Western Pygmy Blue Butterfly

When I was out looking at the Hoary Tansy Asters that have sprung up in the old play yard after the monsoon rains, I noticed an extremely tiny butterfly flitting around one of the lavender flowers fairly low to the ground. It circled the plant several times, alighting on the flower for a few seconds each time. I managed to get some photos.


It took me quite a while to find this butterfly in the butterfly guide, but I was able to identify it by the distinctive spots on the hindwing and the long body. It's a Western Pygmy Blue (Brephidium exilis). Believed to be the smallest butterfly in North America, it averages 15 to 19 mm. in length. I measured the flower across its full diameter - 25 mm., so you can get some idea of the scale of this little creature. There doesn't seem to be much blue on this particular butterfly, which may indicate that its a female.

[Several web sites state that the Western Pygmy Blue butterfly is the smallest in the world. However, on December 2005 its alleged status was supplanted by the discovery of the even smaller Sinai Baton Blue butterfly. The Sinai Baton Blue butterfly lives only on mountainside patches of wild thyme in an arid corner of the Sinai Peninsula in Egypt called Saint Katherine's Protectorate. This tiny butterfly has been the subject of studies of how vulnerable animals will go extinct in the face of rising temperatures.]

10 comments:

robin andrea said...

That really is one tiny butterfly. We have tansy aster blooming here and those flowers are quite small. Your photo compositions are just stunning, pam. Really beautiful.

T. Beth said...

I saw dozens of these tiny butterflies when I went out photographing in Tucson today, and thanks to your timely post identifying them, I already knew what they were. :-)

kerrdelune said...

Good morning, Pam, this wee blue butterfly is gorgeous - I have read about them and seen photos, but as I live in the east (sigh) we do not see Western Pigmy Blues.

lené said...

I guess we're just going to have to go to Egypt to see the smallest, Pam. When should I book the flight for your blogger fan club? :) Your shots are gorgeous! I can't imagine how small that beauty must be.

Mary said...

beautiful litttle butterfly.

Pam in Tucson said...

ra - Tansy asters must be hardy little things to bloom so happily in our hot desert and also up in Washington. Thanks for the compliment.

t.beth - I only saw a loner that day, but since then I've seen them in groups. Looking forward to your photos of them.

kerrdelune - I believe you have the Eastern Pygmy Blue, which is supposed to be quite similar, but not quite as small.

lené - I'd love to go to the Sinai. When does the flight leave?

mary - Thanks to the wonders of photography. I thought it was just a little white butterfly when I photographed it. I was amazed at the colour and design when I enlarged the photo.

Endment said...

O-o-o-o-o-oooo
A-h-h-h-h-h

TDharma said...

oh. my. gawd. beautiful! I could just stare and stare and stare....

Pam in Tucson said...

endment, td - thanks!

Kerri said...

What a lucky find. You sure are good with that camera! I've enjoyed catching up with your posts.
The squirrel is adorable too. Thanks for all the interesting information.