Living just north of Madrid means I get to see the spectacular Cardinal Fritillary. For the benefit of those living in the UK I post below some photos taken today.
The upper wings of the female Cardinal are very similar to the Silver Washed except that they should have a greenish tinge. However, the green tinge - which I believe is the result of phosphorescence - is very dependent on the angle of the light. So the first photo shows a typical presentation with very little green being visible.
She then flew onto a different flower head and proceeded to dance around as she drank the nectar from the various flowers. I took a sequence of photos as the colours on her wings progressed to show ever more colour. This next shot shows enough green to make it clearly distinguishable from a Silver Washed
But as she danced around the flower head she eventually caught the sun at such an angle as to show off the most wonderful colours. In this final shot the left wing has a deep green hue while the right is showing red at the root of the wing (aerial navigators beware - should be red to port!!!)
If you visit Spain in the summer be sure to look out for this very colourful butterfly.
Dare I say it: may be due to senescence?!
(we're all getting there at one rate or another)
Very interesting Royal Society discourse on iridescence
- http://rsif.royalsocietypublishing.org/site/misc/iridescence.xhtml (and links therein)