Clouded Yellow Colias croceus

Whenever I have seen a clouded yellow butterfly, it has been flying past at fairly high speed and has not landed for more than a brief moment. This specimen was an exception but unfortunately its wings are quite tatty so will have to do until I meet an obliging specimen in good shape. When it did land it immediately shut it's wings and so the only way to get an open wing shot was to wait until it flew and try and react quickly enough - mostly without success. (See below)