I didn't even know I had this photo until I revisited a collection looking for good plant photos. This was taken on the Great Orme where there is a distinct sub-species of this butterfly but to confuse matters the usual sub species also flies there. The markings on this one suggest ssp argus and not ssp caernensis.

Great Orme, 18th July 2002

Added on 7th October 2004, amended on January 31st and February 7th 2005, updated 27th June 2008