Agriades aquilo - Arctic Blue
This was another species I really hoped to find on my visit to Northern Norway in 2018. It took some doing, but with a couple of clues as to location, I eventually tracked them down and managed some reasonable butterfly images. They struck me as being totally unlike glandon, to which they are often referred to as a subspecies of, much smaller, silvery, even using a different host foodplant, to which they stay close.
The female has some silver "arrowheads", but has a generally pale brown upperside.